Antifungal genes expressed in transgenic pea (Pisum sativum L.) do not affect root colonization of arbuscular mycorrhizae fungi.

PubMed

Kahlon, Jagroop Gill; Jacobsen, Hans-Jörg; Cahill, James F; Hall, Linda M

2017-10-01

Genetically modified crops have raised concerns about unintended consequences on non-target organisms including beneficial soil associates. Pea transformed with four antifungal genes 1-3 β glucanase, endochitinase, polygalacturonase-inhibiting proteins, and stilbene synthase is currently under field-testing for efficacy against fungal diseases in Canada. Transgenes had lower expression in the roots than leaves in greenhouse experiment. To determine the impact of disease-tolerant pea or gene products on colonization by non-target arbuscular mycorrhizae and nodulation by rhizobium, a field trial was established. Transgene insertion, as single gene or stacked genes, did not alter root colonization by arbuscular mycorrhiza fungus (AMF) or root nodulation by rhizobium inoculation in the field. We found no effect of transgenes on the plant growth and performance although, having a dual inoculant with both AMF and rhizobium yielded higher fresh weight shoot-to-root ratio in all the lines tested. This initial risk assessment of transgenic peas expressing antifungal genes showed no deleterious effect on non-target organisms.

7 CFR 301.86-5 - Issuance and cancellation of certificates and limited permits.

Code of Federal Regulations, 2011 CFR

2011-01-01

... plant. (3) Certification requirements for potatoes for consumption, root crops for consumption, garden... for consumption, root crops intended for consumption, garden or dry beans, or peas from the quarantined area only if the field in which the potatoes, root crops, garden or dry beans, or peas were grown...

7 CFR 301.86-5 - Issuance and cancellation of certificates and limited permits.

Code of Federal Regulations, 2014 CFR

2014-01-01

... plant. (3) Certification requirements for potatoes for consumption, root crops for consumption, garden... for consumption, root crops intended for consumption, garden or dry beans, or peas from the quarantined area only if the field in which the potatoes, root crops, garden or dry beans, or peas were grown...

7 CFR 301.86-5 - Issuance and cancellation of certificates and limited permits.

Code of Federal Regulations, 2012 CFR

2012-01-01

... plant. (3) Certification requirements for potatoes for consumption, root crops for consumption, garden... for consumption, root crops intended for consumption, garden or dry beans, or peas from the quarantined area only if the field in which the potatoes, root crops, garden or dry beans, or peas were grown...

Kinetic features of gravicurvature of pea (Pisum sativum) and cress (Lepidium sativum) roots

NASA Astrophysics Data System (ADS)

Polishchuk, O. V.

The upper sides of roots oriented horizontally grow more rapidly than the lower sides, causing the root ultimately to grow downward; this phenomenon is known as positive gravitropism. This ability is based on implicit mechanism which is being extensively investigated. Elaborate analysis of kinetic features of gravicurvature may complement the investigation. Pea and cress roots have positive gravitropism as roots of majority of higher plants. Mainly we investigated dependence of gravicurvature angle on time of gravistimulation. Two-day-old seedlings of cress (Lepidium sativum L. cv. P896) and four-day-old pea ones (Pisum sativum L. cv. Damir-2) were placed on 1% agar medium in Petri dishes and turned on angle of gravistimulation. Then they were photographed at the same position each hour of gravistimulation. Photographs were analyzed with the help of Image Tool software program. Both pea and cress roots showed two phases of gravitropic response during gravistimulation for 6 hours when the initial angle of gravistimulation was 135 degrees. Two peaks of the rate of bending were observed. In cress roots, the first peak was much lower and the distance between the two peaks was greater than in pea roots. Curves of gravitropic bending of cress roots grown in agar had one or two inflections while in the case of roots grown on filter paper curves had no inflections. These data are in agreement with the effect of the external medium on the gravitropic curvature of rice roots reported by Staves et al. (1997). Our results may reflect the fact that at least two systems that contribute to gravicurvature may exist in roots. These systems may be ligand-receptor complexes that may be formed with different kinetics in two different regions of the root. The most probable ligand is auxin and the regions appear to be central elongation zone (CEZ) and distal elongation zone (DEZ), that were reported to be centers of tropic bending in roots. Thus, dependence of rate of root bending on time may represent a superposition of at least two constituents. Moreover, differences in kinetics of bending between pea and cress roots may correspond to different kinetic parameters and contribution of the constituents. (Financial support by STCU: NN-13R).

40 CFR 180.589 - Boscalid; tolerances for residues.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., except cowpea, field pea and grain lupin 2.5 Pea and bean, succulent shelled, subgroup 6B, except cowpea....05 Beet, garden, roots 0.1 Beet, sugar, roots 0.1 Cowpea, seed 0.1 Grain, cereal, forage, fodder and...

Differential uptake of photosynthetic and non-photosynthetic proteins by pea root plastids.

PubMed

Yan, Xianxi; Khan, Sultan; Hase, Toshiharu; Emes, Michael J; Bowsher, Caroline G

2006-11-27

The photosynthetic proteins RuBiSCO, ferredoxin I and ferredoxin NADP(+)-oxidoreductase (pFNR) were efficiently imported into isolated pea chloroplasts but not into pea root plastids. By contrast non-photosynthetic ferredoxin III and heterotrophic FNR (hFNR) were efficiently imported into both isolated chloroplasts and root plastids. Chimeric ferredoxin I/III (transit peptide of ferredoxin I attached to the mature region of ferredoxin III) only imported into chloroplasts. Ferredoxin III/I (transit peptide of ferredoxin III attached to the mature region of ferredoxin I) imported into both chloroplasts and root plastids. This suggests that import depends on specific interactions between the transit peptide and the translocon apparatus.

Hydrotropism in pea roots in a porous-tube water delivery system

NASA Technical Reports Server (NTRS)

Takahashi, H.; Brown, C. S.; Dreschel, T. W.; Scott, T. K.; Knott, W. M. (Principal Investigator)

1992-01-01

Orientation of root growth on earth and under microgravity conditions can possibly be controlled by hydrotropism--growth toward a moisture source in the absence of or reduced gravitropism. A porous-tube water delivery system being used for plant growth studies is appropriate for testing this hypothesis since roots can be grown aeroponically in this system. When the roots of the agravitropic mutant pea ageotropum (Pisum sativum L.) were placed vertically in air of 91% relative humidity and 2 to 3 mm from the water-saturated porous tube placed horizontally, the roots responded hydrotropically and grew in a continuous arch along the circular surface of the tube. By contrast, normal gravitropic roots of Alaska' pea initially showed a slight transient curvature toward the tube and then resumed vertical downward growth due to gravitropism. Thus, in microgravity, normal gravitropic roots could respond to a moisture gradient as strongly as the agravitropic roots used in this study. Hydrotropism should be considered a significant factor responsible for orientation of root growth in microgravity.

Effect of Root-Zone Moisture Variations on Growth of Lettuce and Pea Plants

NASA Astrophysics Data System (ADS)

Ilieva, Iliana; Ivanova, Tania

2008-06-01

Variations in substrate moisture lead to changes in water and oxygen availability to plant roots. Ground experiments were carried out in the laboratory prototype of SVET-2 Space Greenhouse to study the effect of variation of root-zone moisture conditions on growth of lettuce and pea plants. The effect of transient increase (for 1 day) and drastic increase (waterlogging for 10 days) of substrate moisture was studied with 16-day old pea and 21-day old lettuce plants respectively. Pea height and fresh biomass accumulation were not affected by transient substrate moisture increase. Net photosynthetic rate (Pn) of pea plants showed fast response to substrate moisture variation, while chlorophyll content did not change. Drastic change of substrate moisture suppressed lettuce Pn, chlorophyll biosynthesis and plant growth. These parameters slowly recovered after termination of waterlogging treatment but lettuce yield was greatly affected. The results showed that the most sensitive physiological parameter to substrate moisture variations is photosynthesis.

Analysis of the state of posttranslational calmodulin methylation in developing pea plants. [Pisum sativum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oh, Sukheung; Roberts, D.M.

1990-07-01

A specific calmodulin-N-methyltransferase was used in a radiometric assay to analyze the degree of methylation of lysine-115 in pea (Pisum sativum) plants. Calmodulin was isolated from dissected segments of developing roots of young etiolated and green pea plants and was tested for its ability to be methylated by incubation with the calmodulin methyltransferase in the presence of ({sup 3}H)methyl-S-adenosylmethionine. By this approach, the presence of unmethylated calmodulins were demonstrated in pea tissues, and the levels of methylation varied depending on the developmental state of the tissue tested. Calmodulin methylation levels were lower in apical root segments of both etiolated andmore » green plants, and in the young lateral roots compared with the mature, differentiated root tissues. The incorporation of methyl groups into these calmodulin samples appears to be specific for position 115 since site-directed mutants of calmodulin with substitutions at this position competitively inhibited methyl group incorporation. The present findings, combined with previous data showing differences in the ability of methylated and unmethylated calmodulins to activate pea NAD kinase raise the possibility that posttranslational methylation of calmodulin could be another mechanism for regulating calmodulin activity.« less

Sub-lethal levels of electric current elicit the biosynthesis of plant secondary metabolites.

PubMed

Kaimoyo, Evans; Farag, Mohamed A; Sumner, Lloyd W; Wasmann, Catherine; Cuello, Joel L; VanEtten, Hans

2008-01-01

Many secondary metabolites that are normally undetectable or in low amounts in healthy plant tissue are synthesized in high amounts in response to microbial infection. Various abiotic and biotic agents have been shown to mimic microorganisms and act as elicitors of the synthesis of these plant compounds. In the present study, sub-lethal levels of electric current are shown to elicit the biosynthesis of secondary metabolites in transgenic and non-transgenic plant tissue. The production of the phytoalexin (+)-pisatin by pea was used as the main model system. Non-transgenic pea hairy roots treated with 30-100 mA of electric current produced 13 times higher amounts of (+)-pisatin than did the non-elicited controls. Electrically elicited transgenic pea hairy root cultures blocked at various enzymatic steps in the (+)-pisatin biosynthetic pathway also accumulated intermediates preceding the blocked enzymatic step. Secondary metabolites not usually produced by pea accumulated in some of the transgenic root cultures after electric elicitation due to the diversion of the intermediates into new pathways. The amount of pisatin in the medium bathing the roots of electro-elicited roots of hydroponically cultivated pea plants was 10 times higher 24 h after elicitation than in the medium surrounding the roots of non-elicited control plants, showing not only that the electric current elicited (+)-pisatin biosynthesis but also that the (+)-pisatin was released from the roots. Seedlings, intact roots or cell suspension cultures of fenugreek (Trigonella foenum-graecum), barrel medic, (Medicago truncatula), Arabidopsis thaliana, red clover (Trifolium pratense) and chickpea (Cicer arietinum) also produced increased levels of secondary metabolites in response to electro-elicitation. On the basis of our results, electric current would appear to be a general elicitor of plant secondary metabolites and to have potential for application in both basic and commercial research.

Roots of symptom-free leguminous cover crop and living mulch species harbor diverse Fusarium communities that show highly variable aggressiveness on pea (Pisum sativum)

PubMed Central

Baćanović-Šišić, Jelena; Karlovsky, Petr; Wittwer, Raphaël; Walder, Florian; Campiglia, Enio; Radicetti, Emanuele; Friberg, Hanna; Baresel, Jörg Peter; Finckh, Maria R.

2018-01-01

Leguminous cover crop and living mulch species show not only great potential for providing multiple beneficial services to agro-ecosystems, but may also present pathological risks for other crops in rotations through shared pathogens, especially those of the genus Fusarium. Disease severity on roots of subterranean clover, white clover, winter and summer vetch grown as cover crop and living mulch species across five European sites as well as the frequency, distribution and aggressiveness to pea of Fusarium spp. recovered from the roots were assessed in 2013 and 2014. Disease symptoms were very low at all sites. Nevertheless, out of 1480 asymptomatic roots, 670 isolates of 14 Fusarium spp. were recovered. The most frequently isolated species in both years from all hosts were F. oxysporum and F. avenaceum accounting for 69% of total isolation percentage. They were common at the Swiss, Italian and German sites, whereas at the Swedish site F. oxysporum dominated and F. avenaceum occurred only rarely. The agressiveness and effect on pea biomass were tested in greenhouse assays for 72 isolates of six Fusarium species. Isolates of F. avenaceum caused severe root rot symptoms with mean severity index (DI) of 82 and 74% mean biomass reduction compared to the non-inoculated control. Fusarium oxysporum and F. solani isolates were higly variable in agressiveness and their impact on pea biomass. DI varied between 15 and 50 and biomass changes relative to the non-inoculated control -40% to +10%. Isolates of F. tricinctum, F. acuminatum and F. equiseti were non to weakly agressive often enhancing pea biomass. This study shows that some of the major pea pathogens are characterized by high ecological plasticity and have the ability to endophytically colonize the hosts studied that thus may serve as inoculum reservoir for susceptible main legume grain crops such as pea. PMID:29444142

Changes in the protein patterns in pea (Pisum sativum L.) roots under the influence of long- and short-term chilling stress and post-stress recovery.

PubMed

Badowiec, Anna; Swigonska, Sylwia; Weidner, Stanisław

2013-10-01

Amongst many factors restricting geographical distribution of plants and crop productivity, low temperature is one of the most important. To gain better understanding of the molecular response of germinating pea (Pisum sativum L.) to low temperature, we investigated the influence of long and short chilling stress as well as post-stress recovery on the alterations in the root proteomes. The impact of long stress was examined on the pea seeds germinating in the continuous chilling conditions of 10 °C for 8 days (LS). To examine the impact of short stress, pea seeds germinating for 72 h in the optimal temperature of 20 °C were subjected to 24-h chilling (SS). Additionally, both stress treatments were followed by 24 h of recovery in the optimal conditions (accordingly LSR and SR). Using the 2D gel electrophoresis and MALDI-TOF MS protein identification, it was revealed, that most of the proteins undergoing regulation under the applied conditions were implicated in metabolism, protection against stress, cell cycle regulation, cell structure maintenance and hormone synthesis, which altogether may influence root growth and development in the early stages of plant life. The obtained results have shown that most of detected alterations in the proteome patterns of pea roots are dependent on stress duration. However, there are some analogical response pathways which are triggered regardless of stress length. The functions of proteins which accumulation has been changed by chilling stress and post-stress recovery are discussed here in relation to their impact on pea roots development. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Remediation of cadmium toxicity in field peas (Pisum sativum L.) through exogenous silicon.

PubMed

Rahman, Mohammad Farhadur; Ghosal, Anubrata; Alam, Mohammad Firoz; Kabir, Ahmad Humayan

2017-01-01

Cadmium (Cd) is an important phytotoxic element causing health hazards. This work investigates whether and how silicon (Si) influences the alleviation of Cd toxicity in field peas at biochemical and molecular level. The addition of Si in Cd-stressed plants noticeably increased growth and development as well as total protein and membrane stability of Cd-stressed plants, suggesting that Si does have critical roles in Cd detoxification in peas. Furthermore, Si supplementation in Cd-stressed plants showed simultaneous significant increase and decrease of Cd and Fe in roots and shoots, respectively, compared with Cd-stressed plants. At molecular level, GSH1 (phytochelatin precursor) and MT A (metallothionein) transcripts predominantly expressed in roots and strongly induced due to Si supplementation in Cd-stressed plants compared with Cd-free conditions, suggesting that these chelating agents may bind to Cd leading to vacuolar sequestration in roots. Furthermore, pea Fe transporter (RIT1) showed downregulation in shoots when plants were treated with Si along with Cd compared with Cd-treated conditions. It is consistent with the physiological observations and supports the conclusion that alleviation of Cd toxicity in pea plants might be associated with Cd sequestration in roots and reduced Cd translocation in shoots through the regulation of Fe transport. Furthermore, increased CAT, POD, SOD and GR activity along with elevated S-metabolites (cysteine, methionine, glutathione) implies the active involvement of ROS scavenging and plays, at least in part, to the Si-mediated alleviation of Cd toxicity in pea. The study provides first mechanistic evidence on the beneficial effect of Si on Cd toxicity in pea plants. Copyright © 2016 Elsevier Inc. All rights reserved.

Interactive Effects of CO2 and O2 in Soil on Root and Top Growth of Barley and Peas

PubMed Central

Geisler, G.

1967-01-01

Barley and pea plants were grown under several regimens of different compositions of soil atmosphere, the O2 concentration varying from 0 to 21% and the CO2 concentration from 0 to 8%. In absence of CO2, the effect of O2 on root length in barley was characterized by equal root lengths within the range of 21 to 7% O2 and a steep decline between 7 and 0%. In peas, while showing the same general response, the decline occurred between 14 and 7% O2. Root numbers of the seminal roots of barley decreased already with reduction in O2 concentration from 21 to 14%. Dry matter production was affected somewhat differently by O2 and CO2 concentration. Dry matter production in barley was reduced at 14% O2 while root length decreased between 7 and 0%. In peas, dry matter production was favored by low CO2 concentrations except where there was no oxygen. At 21% O2, increasing CO2 concentrations did not seem to affect root length up to concentrations of 2% CO2. At 8% CO2, root length was decreased. The inter-active effects of CO2 and O2 are characterized by a reduced susceptibility to CO2 at O2 values below 7%, and a very deleterious effect of 8% CO2 at 7% O2. PMID:16656508

Cell Wall Pectin and its Methyl-esterification in Transition Zone Determine Al Resistance in Cultivars of Pea (Pisum sativum)

PubMed Central

Li, Xuewen; Li, Yalin; Qu, Mei; Xiao, Hongdong; Feng, Yingming; Liu, Jiayou; Wu, Lishu; Yu, Min

2016-01-01

The initial response of plants to aluminum (Al) is the inhibition of root elongation, while the transition zone is the most Al sensitive zone in the root apex, which may sense the presence of Al and regulate the responses of root to Al toxicity. In the present study, the effect of Al treatment (30 μM, 24 h) on root growth, Al accumulation, and properties of cell wall of two pea (Pisum sativum L.) cultivars, cv Onward (Al-resistant) and cv Sima (Al-sensitive), were studied to disclose whether the response of root transition zone to Al toxicity determines Al resistance in pea cultivars. The lower relative root elongation (RRE) and higher Al content were founded in cv Sima compared with cv Onward, which were related to Al-induced the increase of pectin in root segments of both cultivars. The increase of pectin is more prominent in Al-sensitive cultivar than in Al-resistant cultivar. Aluminum toxicity also induced the increase of pectin methylesterases (PME), which is 2.2 times in root transition zone in Al-sensitive cv Sima to that of Al resistant cv Onward, thus led to higher demethylesterified pectin content in root transition zone of Al-sensitive cv Sima. The higher demethylesterified pectin content in root transition zone resulted in more Al accumulation in the cell wall and cytosol in Al-sensitive cv Sima. Our results provide evidence that the increase of pectin content and PME activity under Al toxicity cooperates to determine Al sensitivity in root transition zone that confers Al resistance in cultivars of pea (Pisum sativum). PMID:26870060

Genetic ablation of root cap cells in Arabidopsis

NASA Technical Reports Server (NTRS)

Tsugeki, R.; Fedoroff, N. V.

1999-01-01

The root cap is increasingly appreciated as a complex and dynamic plant organ. Root caps sense and transmit environmental signals, synthesize and secrete small molecules and macromolecules, and in some species shed metabolically active cells. However, it is not known whether root caps are essential for normal shoot and root development. We report the identification of a root cap-specific promoter and describe its use to genetically ablate root caps by directing root cap-specific expression of a diphtheria toxin A-chain gene. Transgenic toxin-expressing plants are viable and have normal aerial parts but agravitropic roots, implying loss of root cap function. Several cell layers are missing from the transgenic root caps, and the remaining cells are abnormal. Although the radial organization of the roots is normal in toxin-expressing plants, the root tips have fewer cytoplasmically dense cells than do wild-type root tips, suggesting that root meristematic activity is lower in transgenic than in wild-type plants. The roots of transgenic plants have more lateral roots and these are, in turn, more highly branched than those of wild-type plants. Thus, root cap ablation alters root architecture both by inhibiting root meristematic activity and by stimulating lateral root initiation. These observations imply that the root caps contain essential components of the signaling system that determines root architecture.

Characterizing pathways by which gravitropic effectors could move from the root cap to the root of primary roots of Zea mays

NASA Technical Reports Server (NTRS)

Moore, R.; McClelen, C. E.

1989-01-01

Plasmodesmata linking the root cap and root in primary roots Zea mays are restricted to approx. 400 protodermal cells bordering approx. 110000 microns2 of the calyptrogen of the root cap. This area is less than 10% of the cross-sectional area of the root-tip at the cap junction. Therefore, gravitropic effectors moving from the root cap to the root can move symplastically only through a relatively small area in the centre of the root. Decapped roots are non-responsive to gravity. However, decapped roots whose caps are replaced immediately after decapping are strongly graviresponsive. Thus, gravicurvature occurs only when the root cap contacts the root, and symplastic continuity between the cap and root is not required for gravicurvature. Completely removing mucilage from the root tip renders the root non-responsive to gravity. Taken together, these data suggest that gravitropic effectors move apoplastically through mucilage from the cap to the root.

Seventeen years of research on genetics of resistance to Aphanomyces root rot of pea

USDA-ARS?s Scientific Manuscript database

Aphanomyces root rot, caused by the oomycete Aphanomyces euteiches, is a major soil borne disease of pea in many countries. Genetic resistance is considered to be a main way to control the disease. Since 2000, INRA has engaged a long-term research program to study genetic resistance to A. euteiches ...

Inhibition of strigolactones promotes adventitious root formation

PubMed Central

Beveridge, Christine A.; Geelen, Danny

2012-01-01

Roots that form from non-root tissues (adventitious roots) are crucial for cutting propagation in the forestry and horticulture industries. Strigolactone has been demonstrated to be an important regulator of these roots in both Arabidopsis and pea using strigolactone deficient mutants and exogenous hormone applications. Strigolactones are produced from a carotenoid precursor which can be blocked using the widely available but broad terpenoid biosynthesis blocker, fluridone. We demonstrate here that fluridone can be used to promote adventitious rooting in the model species Pisum sativum (pea). In addition, in the garden species Plumbago auriculata and Jasminium polyanthum fluridone was equally as successful at promoting roots as a commercial rooting compound containing NAA and IBA. Our findings demonstrate that inhibition of strigolactone signaling has the potential to be used to improve adventitious rooting in commercially relevant species. PMID:22580687

Electrotropism of maize roots. Role of the root cap and relationship to gravitropism

NASA Technical Reports Server (NTRS)

Ishikawa, H.; Evans, M. L.

1990-01-01

We examined the kinetics of electrotropic curvature in solutions of low electrolyte concentration using primary roots of maize (Zea mays L., variety Merit). When submerged in oxygenated solution across which an electric field was applied, the roots curved rapidly and strongly toward the positive electrode (anode). The strength of the electrotropic response increased and the latent period decreased with increasing field strength. At a field strength of 7.5 volts per centimeter the latent period was 6.6 minutes and curvature reached 60 degrees in about 1 hour. For electric fields greater than 10 volts per centimeter the latent period was less than 1 minute. There was no response to electric fields less than 2.8 volts per centimeter. Both electrotropism and growth were inhibited when indoleacetic acid (10 micromolar) was included in the medium. The auxin transport inhibitor pyrenoylbenzoic acid strongly inhibited electrotropism without inhibiting growth. Electrotropism was enhanced by treatments that interfere with gravitropism, e.g. decapping the roots or pretreating them with ethyleneglycol-bis-[beta-ethylether]-N,N,N',N' -tetraacetic acid. Similarly, roots of agravitropic pea (Pisum sativum, variety Ageotropum) seedlings were more responsive to electrotropic stimulation than roots of normal (variety Alaska) seedlings. The data indicate that the early steps of gravitropism and electrotropism occur by independent mechanisms. However, the motor mechanisms of the two responses may have features in common since auxin and auxin transport inhibitors reduced both gravitropism and electrotropism.

Inducing gravitropic curvature of primary roots of Zea mays cv Ageotropic

NASA Technical Reports Server (NTRS)

Moore, R.; Evans, M. L.; Fondren, W. M.

1990-01-01

Primary roots of the mutant 'Ageotropic' cultivar of Zea mays are nonresponsive to gravity. Their root caps secrete little or no mucilage and touch the root only at the extreme apex. A gap separates the cap and root at the periphery of the cap. Applying mucilage from normal roots or substances with a consistency similar to that of mucilage to tips of mutant roots causes these roots to become strongly graviresponsive. Gravicurvature stops when these substances are removed. Caps of some mutants secrete small amounts of mucilage and are graviresponsive. These results indicate that (a) the lack of graviresponsiveness in the mutant results from disrupting the transport pathway between the cap and root, (b) movement of the growth-modifying signal from the cap to the root occurs via an apoplastic pathway, and (c) mucilage is necessary for normal communication between the root cap and root in Zea mays cv Ageotropic.

A germin-like protein with superoxide dismutase activity in pea nodules with high protein sequence identity to a putative rhicadhesin receptor.

PubMed

Gucciardo, Sébastian; Wisniewski, Jean-Pierre; Brewin, Nicholas J; Bornemann, Stephen

2007-01-01

The cDNAs encoding three germin-like proteins (PsGER1, PsGER2a, and PsGER2b) were isolated from Pisum sativum. The coding sequence of PsGER1 transiently expressed in tobacco leaves gave a protein with superoxide dismutase activity but no detectable oxalate oxidase activity according to in-gel activity stains. The transient expression of wheat germin gf-2.8 oxalate oxidase showed oxalate oxidase but no superoxide dismutase activity under the same conditions. The superoxide dismutase activity of PsGER1 was resistant to high temperature, denaturation by detergent, and high concentrations of hydrogen peroxide. In salt-stressed pea roots, a heat-resistant superoxide dismutase activity was observed with an electrophoretic mobility similar to that of the PsGER1 protein, but this activity was below the detection limit in non-stressed or H(2)O(2)-stressed pea roots. Oxalate oxidase activity was not detected in either pea roots or nodules. Following in situ hybridization in developing pea nodules, PsGER1 transcript was detected in expanding cells just proximal to the meristematic zone and also in the epidermis, but to a lesser extent. PsGER1 is the first known germin-like protein with superoxide dismutase activity to be associated with nodules. It shared protein sequence identity with the N-terminal sequence of a putative plant receptor for rhicadhesin, a bacterial attachment protein. However, its primary location in nodules suggests functional roles other than as a rhicadhesin receptor required for the first stage of bacterial attachment to root hairs.

Thiamine

MedlinePlus

... potatoes, whole-grain cereals and breads, meats (especially pork and liver), peas, beans, and nuts to increase ... To protect young children from poisoning, always lock safety caps and immediately place the medication in a ...

Phenotyping: Using Machine Learning for Improved Pairwise Genotype Classification Based on Root Traits

PubMed Central

Zhao, Jiangsan; Bodner, Gernot; Rewald, Boris

2016-01-01

Phenotyping local crop cultivars is becoming more and more important, as they are an important genetic source for breeding – especially in regard to inherent root system architectures. Machine learning algorithms are promising tools to assist in the analysis of complex data sets; novel approaches are need to apply them on root phenotyping data of mature plants. A greenhouse experiment was conducted in large, sand-filled columns to differentiate 16 European Pisum sativum cultivars based on 36 manually derived root traits. Through combining random forest and support vector machine models, machine learning algorithms were successfully used for unbiased identification of most distinguishing root traits and subsequent pairwise cultivar differentiation. Up to 86% of pea cultivar pairs could be distinguished based on top five important root traits (Timp5) – Timp5 differed widely between cultivar pairs. Selecting top important root traits (Timp) provided a significant improved classification compared to using all available traits or randomly selected trait sets. The most frequent Timp of mature pea cultivars was total surface area of lateral roots originating from tap root segments at 0–5 cm depth. The high classification rate implies that culturing did not lead to a major loss of variability in root system architecture in the studied pea cultivars. Our results illustrate the potential of machine learning approaches for unbiased (root) trait selection and cultivar classification based on rather small, complex phenotypic data sets derived from pot experiments. Powerful statistical approaches are essential to make use of the increasing amount of (root) phenotyping information, integrating the complex trait sets describing crop cultivars. PMID:27999587

Characterization of five fungal endophytes producing Cajaninstilbene acid isolated from pigeon pea [Cajanus cajan (L.) Millsp].

PubMed

Gao, Yuan; Zhao, Jin Tong; Zu, Yuan Gang; Fu, Yu Jie; Wang, Wei; Luo, Meng; Efferth, Thomas

2011-01-01

Five fungal endophytes (K4, K5, K6, K9, K14) producing Cajaninstilbene acid (CSA, 3-hydroxy-4-prenyl-5-methoxystilbene-2-carboxylic acid) were isolated from the roots of pigeon pea [Cajanus cajan (L.) Millsp.]. CSA is responsible for the prominent pharmacological activities in pigeon pea. The amount of CSA in culture solution varied among the five fungal endophytes. K4 produced the highest levels of CSA (1037.13 µg/L) among the endophytes tested after incubation for five days. Both morphological characteristics and molecular methods were used for species identification of fungal endophytes. The five endophytic isolates were characterized by analyzing the internal transcribed spacer (ITS) rRNA and β-tubulin genes. The K4, K5, K9 and K14 strains isolated from pigeon pea roots were found to be closely related to the species Fusarium oxysporum. K6 was identified as Neonectria macrodidym. The present study is the first report on the isolation and identification of fungal endophytes producing CSA in pigeon pea. The study also provides a scientific base for large scale production of CSA.

Defective secretion of mucilage is the cellular basis for agravitropism in primary roots of Zea mays cv. Ageotropic

NASA Technical Reports Server (NTRS)

Miller, I.; Moore, R.

1990-01-01

Root caps of primary, secondary, and seminal roots of Z. mays cv. Kys secrete large amounts of mucilage and are in close contact with the root all along the root apex. These roots are strongly graviresponsive. Secondary and seminal roots of Z. mays cv. Ageotropic are also strongly graviresponsive. Similarly, their caps secrete mucilage and closely appress the root all along the root apex. However, primary roots of Z. mays cv. Ageotropic are non-responsive to gravity. Their caps secrete negligible amounts of mucilage and contact the root only at the extreme apex of the root along the calyptrogen. These roots become graviresponsive when their tips are coated with mucilage or mucilage-like materials. Peripheral cells of root caps of roots of Z. mays cv. Kys contain many dictyosomes associated with vesicles that migrate to and fuse with the plasmalemma. Root-cap cells of secondary and seminal (i.e. graviresponsive) roots of Z. mays cv. Ageotropic are similar to those of primary roots of Z. mays cv. Kys. However, root-cap cells of primary (i.e. non-graviresponsive) roots of Z. mays cv. Ageotropic have distended dictyosomal cisternae filled with an electron-dense, granular material. Large vesicles full of this material populate the cells and apparently do not fuse with the plasmalemma. Taken together, these results suggest that non-graviresponsiveness of primary roots of Z. mays cv. Ageotropic results from the lack of apoplastic continuity between the root and the periphery of the root cap. This is a result of negligible secretion of mucilage by cells along the edge of the root cap which, in turn, appears to be due to the malfunctioning of dictyosomes in these cells.

Interaction between hydrotropism and gravitropism in seedling roots

NASA Astrophysics Data System (ADS)

Kobayashi, A.; Takahashi, A.; Yamazaki, Y.; Kakimoto, Y.; Higashitani, A.; Fujii, N.; Takahashi, H.

Roots display positive hydrotropism in response to a moisture gradient, which could play a role in avoiding drought stress. Because roots also respond to other stimuli such as gravity, touch and light and exhibit gravitropism, thigmotropism and phototropism, respectively, their growth orientation is determined by interaction among those tropisms. We have demonstrated the interaction between hydrotropism and gravitropism. For example, 1) agravitropic roots of pea mutant strongly respond to a moisture gradient and show positive hydrotropism by overcoming gravitropism, 2) in wild type pea roots hydrotropism is weak but pronounced when rotated on clinostat, 3) cucumber roots are positively gravitropic on the ground but become hydrotropic in microgravity, and 4) maize roots change their growth direction depending on the intensities of both gravistimulation and hydrostimulation. Here we found that Arabidopsis roots could display strong hydrotropism by overcoming gravitropism. It was discovered that amyloplasts in the columella cells are rapidly degraded upon exposure to a moisture gradient. Thus, degradation of amyloplasts could reduce the responsiveness to gravity, which could pronounce the hydrotropic response. In hydrotropically stimulated roots of pea seedlings, however, we could not observe a rapid degradation of amyloplasts in the columella cells. These results suggest that mechanism underlying the interaction between hydrotropism and gravitropism differs among plant species. To further study the molecular mechanism of hydrotropism and its interaction with gravitropism, we isolated unique mutants of Arabidopsis of which roots showed either ahydrotropism, reduced hydrotropism or negative hydrotropic response and examined their gravitropism, phototropism, waving response, amyloplast degradation and elongation growth. Based on the characterization of hydrotropic mutants, we will attempt to compare the mechanisms of the two tropisms and to clarify their cross talk for controlling the directional growth of seedling roots.

Exogenous hydrogen peroxide reversibly inhibits root gravitropism and induces horizontal curvature of primary root during grass pea germination.

PubMed

Jiang, Jinglong; Su, Miao; Wang, Liyan; Jiao, Chengjin; Sun, Zhengxi; Cheng, Wei; Li, Fengmin; Wang, Chongying

2012-04-01

During germination in distilled water (dH(2)O) on a horizontally positioned Petri dish, emerging primary roots of grass pea (Lathyrus sativus L.) grew perpendicular to the bottom of the Petri dish, due to gravitropism. However, when germinated in exogenous hydrogen peroxide (H(2)O(2)), the primary roots grew parallel to the bottom of the Petri dish and asymmetrically, forming a horizontal curvature. Time-course experiments showed that the effect was strongest when H(2)O(2) was applied prior to the emergence of the primary root. H(2)O(2) failed to induce root curvature when applied post-germination. Dosage studies revealed that the frequency of primary root curvature was significantly enhanced with increased H(2)O(2) concentrations. This curvature could be directly counteracted by dimethylthiourea (DMTU), a scavenger of H(2)O(2), but not by diphenylene iodonium (DPI) and pyridine, inhibitors of H(2)O(2) production. Exogenous H(2)O(2) treatment caused both an increase in the activities of H(2)O(2)-scavenging enzymes [including ascorbate peroxidase (APX: EC 1.11.1.11), catalase (CAT: EC 1.11.1.6) and peroxidase (POD: EC 1.11.1.7)] and a reduction in endogenous H(2)O(2) levels and root vitality. Although grass pea seeds absorbed exogenous H(2)O(2) during seed germination, DAB staining of paraffin sections revealed that exogenous H(2)O(2) only entered the root epidermis and not inner tissues. These data indicated that exogenously applied H(2)O(2) could lead to a reversible loss of the root gravitropic response and a horizontal curvature in primary roots during radicle emergence of the seedling. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Characterization of Five Fungal Endophytes Producing Cajaninstilbene Acid Isolated from Pigeon Pea [Cajanus cajan (L.) Millsp.

PubMed Central

Zu, Yuan Gang; Fu, Yu Jie; Wang, Wei; Luo, Meng; Efferth, Thomas

2011-01-01

Five fungal endophytes (K4, K5, K6, K9, K14) producing Cajaninstilbene acid (CSA, 3-hydroxy-4-prenyl-5-methoxystilbene-2-carboxylic acid) were isolated from the roots of pigeon pea [Cajanus cajan (L.) Millsp.]. CSA is responsible for the prominent pharmacological activities in pigeon pea. The amount of CSA in culture solution varied among the five fungal endophytes. K4 produced the highest levels of CSA (1037.13 µg/L) among the endophytes tested after incubation for five days. Both morphological characteristics and molecular methods were used for species identification of fungal endophytes. The five endophytic isolates were characterized by analyzing the internal transcribed spacer (ITS) rRNA and β-tubulin genes. The K4, K5, K9 and K14 strains isolated from pigeon pea roots were found to be closely related to the species Fusarium oxysporum. K6 was identified as Neonectria macrodidym. The present study is the first report on the isolation and identification of fungal endophytes producing CSA in pigeon pea. The study also provides a scientific base for large scale production of CSA. PMID:22102911

Systemic Induction of the Defensin and Phytoalexin Pisatin Pathways in Pea (Pisum sativum) against Aphanomyces euteiches by Acetylated and Nonacetylated Oligogalacturonides.

PubMed

Selim, Sameh; Sanssené, Jean; Rossard, Stéphanie; Courtois, Josiane

2017-06-19

Oligogalacturonides (OGs) are known for their powerful ability to stimulate the plant immune system but little is known about their mode of action in pea ( Pisum sativum ). In the present study, we investigated the elicitor activity of two fractions of OGs, with polymerization degrees (DPs) of 2-25, in pea against Aphanomyces euteiches . One fraction was nonacetylated (OGs - Ac) whereas the second one was 30% acetylated (OGs + Ac). OGs were applied by injecting the upper two rachises of the plants at three- and/or four-weeks-old. Five-week-old roots were inoculated with 10⁵ zoospores of A. euteiches . The root infection level was determined at 7, 10 and 14 days after inoculation using the quantitative real-time polymerase chain reaction (qPCR). Results showed significant root infection reductions namely 58, 45 and 48% in the plants treated with 80 µg OGs + Ac and 59, 56 and 65% with 200 µg of OGs - Ac. Gene expression results showed the upregulation of genes involved in the antifungal defensins, lignans and the phytoalexin pisatin pathways and a priming effect in the basal defense, SA and ROS gene markers as a response to OGs. The reduction of the efficient dose in OGs + Ac is suggesting that acetylation is necessary for some specific responses. Our work provides the first evidence for the potential of OGs in the defense induction in pea against Aphanomyces root rot.

Transduction of the Root Gravitropic Stimulus: Can Apical Calcium Regulate Auxin Distribution?

NASA Technical Reports Server (NTRS)

Edwards, K. L.

1985-01-01

The hypothesis was tested that calcium, asymmetrically distributes in the root cap upon reorientation to gravity, affects auxin transport and thereby auxin distribution at the elongation zone. It is assumed that calcium exists in the root cap and is asymmetrically transported in root caps altered from a vertical to a horizontal position and that the meristem, the tissue immediately adjacent to the root cap and lying between the site of gravity perception and the site of gravity response, is essential for mediation of gravitropism. Tip calcium in root gravicurvature was implicated. The capstone evidence is that the root cap has the capacity to polarly translocate exogenous calcium downward when tissue is oriented horizontally, and that exogenous calcium, when supplied asymmetrically at the root tip, induces curvature and dictates the direction of curvature in both vertical and horizontal corn roots.

Involvement of Arabidopsis thaliana phospholipase Dzeta2 in root hydrotropism through the suppression of root gravitropism.

PubMed

Taniguchi, Yukimi Y; Taniguchi, Masatoshi; Tsuge, Tomohiko; Oka, Atsuhiro; Aoyama, Takashi

2010-01-01

Root hydrotropism is the phenomenon of directional root growth toward moisture under water-deficient conditions. Although physiological and genetic studies have revealed the involvement of the root cap in the sensing of moisture gradients, and those of auxin and abscisic acid (ABA) in the signal transduction for asymmetric root elongation, the overall mechanism of root hydrotropism is still unclear. We found that the promoter activity of the Arabidopsis phospholipase Dzeta2 gene (PLDzeta2) was localized to epidermal cells in the distal root elongation zone and lateral root cap cells adjacent to them, and that exogenous ABA enhanced the activity and extended its area to the entire root cap. Although pldzeta2 mutant root caps did not exhibit a morphological phenotype in either the absence or presence of exogenous ABA, the inhibitory effect of ABA on gravitropism, which was significant in wild-type roots, was not observed in pldzeta2 mutant roots. In root hydrotropism experiments, pldzeta2 mutations significantly retarded or disturbed root hydrotropic responses. A drought condition similar to that used in a hydrotropism experiment enhanced the PLDzeta2 promoter activity in the root cap, as did exogenous ABA. These results suggest that PLDzeta2 responds to drought through ABA signaling in the root cap and accelerates root hydrotropism through the suppression of root gravitropism.

Effects of rooting and tree growth of selected woodland species on cap integrity in a mineral capped landfill site.

PubMed

Hutchings, T R; Moffat, A J; Kemp, R A

2001-06-01

The above and below ground growth of three tree species (Alnus glutinosa, Pinus nigra var. maritima and Acer pseudoplatanus) was studied on a containment landfill site at Waterford, Hertfordshire, UK. Tree root architecture was studied using soil inspection pits excavated next to 12 trees of each species and mapped in detail. Tree height was related to soil thickness over the compacted mineral cap. No roots entered the cap where soil thickness was 1.3 m, but a few roots, especially of alder, were observed within it when the soil cover was 1.0 m or less. Micromorphological analysis of undisturbed samples of the mineral cap suggested that roots exploited weaknesses in the cap rather than actively causing penetration into it. Alder roots were more tolerant of anaerobic conditions within the cap than the other species examined. The results confirm that mineral caps should be covered by 1.5 m of soil or soil-forming material if tree establishment is intended over a restored landfill site, unless protected by other parts of a composite capping system.

Strigolactones Suppress Adventitious Rooting in Arabidopsis and Pea1[C][W][OA

PubMed Central

Rasmussen, Amanda; Mason, Michael Glenn; De Cuyper, Carolien; Brewer, Philip B.; Herold, Silvia; Agusti, Javier; Geelen, Danny; Greb, Thomas; Goormachtig, Sofie; Beeckman, Tom; Beveridge, Christine Anne

2012-01-01

Adventitious root formation is essential for the propagation of many commercially important plant species and involves the formation of roots from nonroot tissues such as stems or leaves. Here, we demonstrate that the plant hormone strigolactone suppresses adventitious root formation in Arabidopsis (Arabidopsis thaliana) and pea (Pisum sativum). Strigolactone-deficient and response mutants of both species have enhanced adventitious rooting. CYCLIN B1 expression, an early marker for the initiation of adventitious root primordia in Arabidopsis, is enhanced in more axillary growth2 (max2), a strigolactone response mutant, suggesting that strigolactones restrain the number of adventitious roots by inhibiting the very first formative divisions of the founder cells. Strigolactones and cytokinins appear to act independently to suppress adventitious rooting, as cytokinin mutants are strigolactone responsive and strigolactone mutants are cytokinin responsive. In contrast, the interaction between the strigolactone and auxin signaling pathways in regulating adventitious rooting appears to be more complex. Strigolactone can at least partially revert the stimulatory effect of auxin on adventitious rooting, and auxin can further increase the number of adventitious roots in max mutants. We present a model depicting the interaction of strigolactones, cytokinins, and auxin in regulating adventitious root formation. PMID:22323776

Strigolactones suppress adventitious rooting in Arabidopsis and pea.

PubMed

Rasmussen, Amanda; Mason, Michael Glenn; De Cuyper, Carolien; Brewer, Philip B; Herold, Silvia; Agusti, Javier; Geelen, Danny; Greb, Thomas; Goormachtig, Sofie; Beeckman, Tom; Beveridge, Christine Anne

2012-04-01

Adventitious root formation is essential for the propagation of many commercially important plant species and involves the formation of roots from nonroot tissues such as stems or leaves. Here, we demonstrate that the plant hormone strigolactone suppresses adventitious root formation in Arabidopsis (Arabidopsis thaliana) and pea (Pisum sativum). Strigolactone-deficient and response mutants of both species have enhanced adventitious rooting. CYCLIN B1 expression, an early marker for the initiation of adventitious root primordia in Arabidopsis, is enhanced in more axillary growth2 (max2), a strigolactone response mutant, suggesting that strigolactones restrain the number of adventitious roots by inhibiting the very first formative divisions of the founder cells. Strigolactones and cytokinins appear to act independently to suppress adventitious rooting, as cytokinin mutants are strigolactone responsive and strigolactone mutants are cytokinin responsive. In contrast, the interaction between the strigolactone and auxin signaling pathways in regulating adventitious rooting appears to be more complex. Strigolactone can at least partially revert the stimulatory effect of auxin on adventitious rooting, and auxin can further increase the number of adventitious roots in max mutants. We present a model depicting the interaction of strigolactones, cytokinins, and auxin in regulating adventitious root formation.

A Simple Device to Measure Root Growth Rates

ERIC Educational Resources Information Center

Rauser, Wilfried E.; Horton, Roger F.

1975-01-01

Describes construction and use of a simple auxanometer which students can use to accurately measure root growth rates of intact seedlings. Typical time course data are presented for the effect of ethylene and indole acetic acid on pea root growth. (Author/BR)

Root gravitropism in response to a signal originating outside of the cap

NASA Technical Reports Server (NTRS)

Wolverton, Chris; Mullen, Jack L.; Ishikawa, Hideo; Evans, Michael L.

2002-01-01

We have developed image analysis software linked to a rotating stage, allowing constraint of any user-selected region of a root at a prescribed angle during root gravitropism. This device allows the cap of a graviresponding root to reach vertical while maintaining a selected region within the elongation zone at a gravistimulated angle. Under these conditions gravitropic curvature of roots of Zea mays L. continues long after the root cap reaches vertical, indicating that a signal from outside of the cap can contribute to the curvature response.

Improvement of pea biomass and seed productivity by simultaneous increase of phloem and embryo loading with amino acids.

PubMed

Zhang, Lizhi; Garneau, Matthew G; Majumdar, Rajtilak; Grant, Jan; Tegeder, Mechthild

2015-01-01

The development of sink organs such as fruits and seeds strongly depends on the amount of nitrogen that is moved within the phloem from photosynthetic-active source leaves to the reproductive sinks. In many plant species nitrogen is transported as amino acids. In pea (Pisum sativum L.), source to sink partitioning of amino acids requires at least two active transport events mediated by plasma membrane-localized proteins, and these are: (i) amino acid phloem loading; and (ii) import of amino acids into the seed cotyledons via epidermal transfer cells. As each of these transport steps might potentially be limiting to efficient nitrogen delivery to the pea embryo, we manipulated both simultaneously. Additional copies of the pea amino acid permease PsAAP1 were introduced into the pea genome and expression of the transporter was targeted to the sieve element-companion cell complexes of the leaf phloem and to the epidermis of the seed cotyledons. The transgenic pea plants showed increased phloem loading and embryo loading of amino acids resulting in improved long distance transport of nitrogen, sink development and seed protein accumulation. Analyses of root and leaf tissues further revealed that genetic manipulation positively affected root nitrogen uptake, as well as primary source and sink metabolism. Overall, the results suggest that amino acid phloem loading exerts regulatory control over pea biomass production and seed yield, and that import of amino acids into the cotyledons limits seed protein levels. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.

Aluminum exclusion from root zone and maintenance of nutrient uptake are principal mechanisms of Al tolerance in Pisum sativum L.

PubMed

Kichigina, Natalia E; Puhalsky, Jan V; Shaposhnikov, Aleksander I; Azarova, Tatiana S; Makarova, Natalia M; Loskutov, Svyatoslav I; Safronova, Vera I; Tikhonovich, Igor A; Vishnyakova, Margarita A; Semenova, Elena V; Kosareva, Irina A; Belimov, Andrey A

2017-10-01

Our study aimed to evaluate intraspecific variability of pea ( Pisum sativum L.) in Al tolerance and to reveal mechanisms underlying genotypic differences in this trait. At the first stage, 106 pea genotypes were screened for Al tolerance using root re-elongation assay based on staining with eriochrome cyanine R. The root re-elongation zone varied from 0.5 mm to 14 mm and relationships between Al tolerance and provenance or phenotypic traits of genotypes were found. Tolerance index (TI), calculated as a biomass ratio of Al-treated and non-treated contrasting genotypes grown in hydroponics for 10 days, varied from 30% to 92% for roots and from 38% to 90% for shoots. TI did not correlate with root or shoot Al content, but correlated positively with increasing pH and negatively with residual Al concentration in nutrient solution in the end of experiments. Root exudation of organic acid anions (mostly acetate, citrate, lactate, pyroglutamate, pyruvate and succinate) significantly increased in several Al-treated genotypes, but did not correlate with TI. Al-treatment decreased Ca, Co, Cu, K, Mg, Mn, Mo, Ni, S and Zn contents in roots and/or shoots, whereas contents of several elements (P, B, Fe and Mo in roots and B and Fe in shoots) increased, suggesting that Al toxicity induced substantial disturbances in uptake and translocation of nutrients. Nutritional disturbances were more pronounced in Al sensitive genotypes. In conclusion, pea has a high intraspecific variability in Al tolerance and this trait is associated with provenance and phenotypic properties of plants. Transformation of Al to unavailable (insoluble) forms in the root zone and the ability to maintain nutrient uptake are considered to be important mechanisms of Al tolerance in this plant species.

Effectiveness of rhizobacteria containing ACC deaminase for growth promotion of peas (Pisum sativum) under drought conditions.

PubMed

Zahir, Z A; Munir, A; Asghar, H N; Shaharoona, B; Arshad, M

2008-05-01

A series of experiments were conducted to assess the effectiveness of rhizobacteria containing 1-aminocyclopropane- 1-carboxylate (ACC) deaminase for growth promotion of peas under drought conditions. Ten rhizobacteria isolated from the rhizosphere of different crops (peas, wheat, and maize) were screened for their growth promoting ability in peas under axenic condition. Three rhizobacterial isolates, Pseudomonas fluorescens biotype G (ACC-5), P. fluorescens (ACC-14), and P. putida biotype A (Q-7), were selected for pot trial on the basis of their source, ACC deaminase activity, root colonization, and growth promoting activity under axenic conditions. Inoculated and uninoculated (control) seeds of pea cultivar 2000 were sown in pots (4 seeds/pot) at different soil moisture levels (25, 50, 75, and 100% of field capacity). Results revealed that decreasing the soil moisture levels from 100 to 25% of field capacity significantly decreased the growth of peas. However, inoculation of peas with rhizobacteria containing ACC deaminase significantly decreased the "drought stress imposed effects" on growth of peas, although with variable efficacy at different moisture levels. At the lowest soil moisture level (25% field capacity), rhizobacterial isolate Pseudomonas fluorescens biotype G (ACC-5) was found to be more promising compared with the other isolates, as it caused maximum increases in fresh weight, dry weight, root length, shoot length, number of leaves per plant, and water use efficiency on fresh and dry weight basis (45, 150, 92, 45, 140, 46, and 147%, respectively) compared with respective uninoculated controls. It is highly likely that rhizobacteria containing ACC deaminase might have decreased the drought-stress induced ethylene in inoculated plants, which resulted in better growth of plants even at low moisture levels. Therefore, inoculation with rhizobacteria containing ACC deaminase could be helpful in eliminating the inhibitory effects of drought stress on the growth of peas.

Perfluoroalkyl acid distribution in various plant compartments ...

EPA Pesticide Factsheets

Crop uptake of perfluoroalkyl acids (PFAAs) from biosolids-amended soil has been identified as a potential pathway for PFAA entry into the terrestrial food chain. This study compared the uptake of PFAAs in greenhouse-grown radish (Raphanus sativus), celery (Apium graveolens var.dulce), tomato (Lycopersicon lycopersicum), and sugar snap pea (Pisum sativum var. macrocarpon) from an industrially impacted biosolids-amended soil, a municipal biosolids­ amended soil, and a control soil. Individual concentrations of PFAAs, on a dry weight basis, in mature, edible portions of crops grown in soil amended with PFAA industrially impacted biosolids were highest for perfluorooctanoate (PFOA; 67 ng/g) in radish root, perfluorobutanoate (PFBA;232 ng/g) in celery shoot, and PFBA (150 ng/g) in pea fruit. Comparatively, PFAA concentrations in edible compartments of crops grown in the municipal biosolids-amended soil and in the control soil were less than 25 ng/g. Bioaccumulation factors (BAFs) were calculated for the root, shoot, and fruit compartments (as applicable) of all crops grown in the industrially impacted soil. BAFs were highest for PFBA in the shoots of all crops, as well as in the fruit compartment of pea. Root­ soil concentration factors (RCFs) for tomato and pea were independent of PFAA chain length, while radish and celery RCFs showed a slight decrease with increasing chain length. Shoot-soil concentration factors (SCFs) for all crops showed a decrease with incre

The pea stem

PubMed Central

Karahara, Ichirou

2012-01-01

The Casparian strip is commonly observed in the endodermis of roots of vascular plants and, in some cases, also in the stems. Pea stems develop the Casparian strip, and its development has been reported to be regulated by blue light. In addition, for the purpose of photobiological studies, pea stems provide a unique experimental system for other physiological studies of the development of the Casparian strip. In this article, I have briefly summarized (1) the effects of environmental factors on the development of the Casparian strip, (2) the advantage of using pea stems for physiological studies of the development of the Casparian strip, and (3) cellular events indicated to be involved in the development of the Casparian strip, focusing on the studies using pea stems as well as other recent studies. PMID:22899074

Short term physiological implications of NBPT application on the N metabolism of Pisum sativum and Spinacea oleracea.

PubMed

Cruchaga, Saioa; Artola, Ekhiñe; Lasa, Berta; Ariz, Idoia; Irigoyen, Ignacio; Moran, Jose Fernando; Aparicio-Tejo, Pedro M

2011-03-01

The application of urease inhibitors in conjunction with urea fertilizers as a means of reducing N loss due to ammonia volatilization requires an in-depth study of the physiological effects of these inhibitors on plants. The aim of this study was to determine how the urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT) affects N metabolism in pea and spinach. Plants were cultivated in pure hydroponic culture with urea as the sole N source. After 2 weeks of growth for pea, and 3 weeks for spinach, half of the plants received NBPT in their nutrient solution. Urease activity, urea and ammonium content, free amino acid composition and soluble protein were determined in leaves and roots at days 0, 1, 2, 4, 7 and 9, and the NBPT content in these tissues was determined 48h after inhibitor application. The results suggest that the effects of NBPT on spinach and pea urease activity differ, with pea being most affected by this treatment, and that the NBPT absorbed by the plant caused a clear inhibition of the urease activity in pea leaf and roots. The high urea concentration observed in leaves was associated with the development of necrotic leaf margins, and was further evidence of NBPT inhibition in these plants. A decrease in the ammonium content in roots, where N assimilation mainly takes place, was also observed. Consequently, total amino acid contents were drastically reduced upon NBPT treatment, indicating a strong alteration of the N metabolism. Furthermore, the amino acid profile showed that amidic amino acids were major components of the reduced pool of amino acids. In contrast, NBPT was absorbed to a much lesser degree by spinach plants than pea plants (35% less) and did not produce a clear inhibition of urease activity in this species. Copyright © 2010 Elsevier GmbH. All rights reserved.

Limiting an Insect Infestation of Nitrogen-Fixing Root Nodules of the Pigeon Pea (Cajanus cajan) by Engineering the Expression of an Entomocidal Gene in Its Root Nodules

PubMed Central

Nambiar, P. T. C.; Ma, S.-W.; Iyer, V. N.

1990-01-01

A region of DNA which determined the production of the insecticidal toxin of Bacillus thuringiensis subsp. israelensis was cloned into a derivative of a broad-host-range group IncQ plasmid vector of gram-negative bacteria. The plasmid which we constructed was transferred by conjugative mobilization into a Bradyrhizobium species that nodulates pigeon peas. In this species the construction was maintained stably in the absence of selection and expressed the gene that was installed. Experiments in a greenhouse with the strain which we constructed indicated that this organism provides protection against root nodule damage by the larvae of the insect Rivellia angulata (Diptera). Images PMID:16348294

Heat stress increases the efficiency of EDTA in phytoextraction of heavy metals.

PubMed

Chen, Ya-Hua; Mao, Ying; He, Shi-Bin; Guo, Peng; Xu, Ke

2007-04-01

Solution culture and pot experiments were carried out to investigate the effects of root damage on phytoextraction of heavy metals. In hydroponics, roots of corn (Zea mays L.) seedlings were pretreated with heating stress, and then were exposed to 250 microM Pb+250 microM EDTA solutions for 7d. The results showed that the preheating treatment significantly increased Pb transportation from roots to shoots. In pot experiments, the effect of hot EDTA solution (95 degrees C) on the accumulation of heavy metal in the shoot of corn and pea (Pisum sativum L.) was also examined. Compared to normal EDTA (25 degrees C) treatment, application of hot EDTA solution to the soil surface increased the total removal of Pb in shoots of corn and pea by about 8- and 12-fold, respectively, in an artificially multimetal-contaminated soil. In addition, hot EDTA solution increased the shoot Cu removal by about 6-fold for corn and 9-fold for pea, respectively, in a naturally Cu-contaminated soil. These results suggested that exposure of roots to high temperature could increase the efficiency of EDTA on the accumulation of heavy metals in shoots. This new approach can help to minimize the amount of chelate applied in the field and reduce the potential risk of heavy metals' leaching.

[Graviresponse in higher plants and its regulation in molecular bases: relevance to growth and development, and auxin polar transport in etiolated pea seedlings].

PubMed

Ueda, Junichi; Miyamoto, Kensuke

2003-08-01

We review the graviresponse under true and simulated microgravity conditions on a clinostat in higher plants, and its regulation in molecular bases, especially on the aspect of auxin polar transport in etiolated pea (Pisum sativum L. cv. Alaska) seedlings which were the plant materials subjected to STS-95 space experiments. True and simulated microgravity conditions substantially affected growth and development in etiolated pea seedlings, especially the direction of growth of stems and roots, resulting in automorphosis. In etiolated pea seedlings grown in space, epicotyls were the most oriented toward the direction far from the cotyledons, and roots grew toward the aerial space of Plant Growth Chamber. Automorphosis observed in space were well simulated by a clinorotation on a 3-dimensional clinostat and also phenocopied by the application of auxin polar transport inhibitors of 2,3,5-triiodobenzoic acid, N-(1-naphtyl)phthalamic acid and 9-hydroxyfluorene-9-carboxylic acid. Judging from the results described above together with the fact that activities of auxin polar transport in epicotyls of etiolated pea seedlings grown in space substantially were reduced, auxin polar transport seems to be closely related to automorphosis. Strenuous efforts to learn in molecular levels how gravity contributes to the auxin polar transport in etiolated pea epicotyls resulted in successful identification of PsPIN2 and PsAUX1 genes located in plasma membrane which products are considered to be putative efflux and influx carriers of auxin, respectively. Based on the results of expression of PsPIN2 and PsAUX1 genes under various gravistimulations, a possible role of PsPIN2 and PsAUX1 genes for auxin polar transport in etiolated pea seedlings will be discussed.

78 FR 7266 - Alpha-Cypermethrin; Pesticide Tolerances

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-01

... confidential pursuant to 40 CFR part 2 may be disclosed publicly by EPA without prior notice. Submit the non...- cypermethrin in or on tree nuts, Group 14; dried shelled pea and bean, except soybean, subgroup 6C; corn, grain... shelled pea and bean, subgroup 6B; and root and tuber vegetables, Group 1 at 0.1 ppm; cucurbit vegetables...

75 FR 17564 - Chlorantraniliprole; Extension of Time-Limited Pesticide Tolerances

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-07

... at 0.20 ppm; grass, forage, fodder and hay, crop group 17 at 0.20 ppm; vegetable, leaves of root and... hay (includes cowpea, forage and hay; field pea, vines and hay); grass, forage, fodder and hay, crop...-limited tolerances for cowpea, forage and hay; field pea, vines and hay; grass, forage, fodder and hay...

Effects of nano-ZnO on the agronomically relevant Rhizobium-legume symbiosis

USDA-ARS?s Scientific Manuscript database

The impact of nano-ZnO (nZnO) on Rhizobium-legume symbiosis was studied with garden pea and its compatible bacterial partner Rhizobium leguminosarum bv. viciae 3841. Exposure of peas to nZnO had no impact on germination, but significantly affected root length. Chronic exposure of plant to nZnO impac...

Effects of nano-TiO2 on the agronomically-relevant Rhizobium-legume symbiosis

USDA-ARS?s Scientific Manuscript database

The impact of nano-TiO2 on Rhizobium-legume symbiosis was studied using garden peas and the compatible bacterial partner Rhizobium leguminosarum bv. viciae 3841. Exposure to nano-TiO2 did not affect the germination of peas grown aseptically, nor did it impact the gross root structure. However, nano-...

A role for the root cap in root branching revealed by the non-auxin probe naxillin.

PubMed

De Rybel, Bert; Audenaert, Dominique; Xuan, Wei; Overvoorde, Paul; Strader, Lucia C; Kepinski, Stefan; Hoye, Rebecca; Brisbois, Ronald; Parizot, Boris; Vanneste, Steffen; Liu, Xing; Gilday, Alison; Graham, Ian A; Nguyen, Long; Jansen, Leentje; Njo, Maria Fransiska; Inzé, Dirk; Bartel, Bonnie; Beeckman, Tom

2012-09-01

The acquisition of water and nutrients by plant roots is a fundamental aspect of agriculture and strongly depends on root architecture. Root branching and expansion of the root system is achieved through the development of lateral roots and is to a large extent controlled by the plant hormone auxin. However, the pleiotropic effects of auxin or auxin-like molecules on root systems complicate the study of lateral root development. Here we describe a small-molecule screen in Arabidopsis thaliana that identified naxillin as what is to our knowledge the first non-auxin-like molecule that promotes root branching. By using naxillin as a chemical tool, we identified a new function for root cap-specific conversion of the auxin precursor indole-3-butyric acid into the active auxin indole-3-acetic acid and uncovered the involvement of the root cap in root branching. Delivery of an auxin precursor in peripheral tissues such as the root cap might represent an important mechanism shaping root architecture.

A role for the root cap in root branching revealed by the non-auxin probe naxillin

PubMed Central

De Rybel, Bert; Audenaert, Dominique; Xuan, Wei; Overvoorde, Paul; Strader, Lucia C; Kepinski, Stefan; Hoye, Rebecca; Brisbois, Ronald; Parizot, Boris; Vanneste, Steffen; Liu, Xing; Gilday, Alison; Graham, Ian A; Nguyen, Long; Jansen, Leentje; Njo, Maria Fransiska; Inzé, Dirk; Bartel, Bonnie; Beeckman, Tom

2013-01-01

The acquisition of water and nutrients by plant roots is a fundamental aspect of agriculture and strongly depends on root architecture. Root branching and expansion of the root system is achieved through the development of lateral roots and is to a large extent controlled by the plant hormone auxin. However, the pleiotropic effects of auxin or auxin-like molecules on root systems complicate the study of lateral root development. Here we describe a small-molecule screen in Arabidopsis thaliana that identified naxillin as what is to our knowledge the first non-auxin-like molecule that promotes root branching. By using naxillin as a chemical tool, we identified a new function for root cap-specific conversion of the auxin precursor indole-3-butyric acid into the active auxin indole-3-acetic acid and uncovered the involvement of the root cap in root branching. Delivery of an auxin precursor in peripheral tissues such as the root cap might represent an important mechanism shaping root architecture. PMID:22885787

Isolation and Structural Studies of Mitochondria from Pea Roots.

PubMed

Vishwakarma, Abhaypratap; Gupta, Kapuganti Jagadis

2017-01-01

For structural and respiratory studies, isolation of intact and active mitochondria is essential. Here, we describe an isolation method which gave good yield and intact mitochondria from 2-week-old pea (Pisum sativum) roots grown hydroponically under standard growth conditions. We used Percoll gradient centrifugation for this isolation procedure. The yield of purified mitochondria was 50 μg/g FW. Isolated mitochondria maintained their structure which was observed by using MitoTracker green in confocal microscope and scanning electron microscopy (SEM). Intact mitochondria are clearly visible in SCM images. Taken together this isolation method can be used for physiological and microscopic studies on mitochondria.

Plant hormones in arbuscular mycorrhizal symbioses: an emerging role for gibberellins.

PubMed

Foo, Eloise; Ross, John J; Jones, William T; Reid, James B

2013-05-01

Arbuscular mycorrhizal symbioses are important for nutrient acquisition in >80 % of terrestrial plants. Recently there have been major breakthroughs in understanding the signals that regulate colonization by the fungus, but the roles of the known plant hormones are still emerging. Here our understanding of the roles of abscisic acid, ethylene, auxin, strigolactones, salicylic acid and jasmonic acid is discussed, and the roles of gibberellins and brassinosteroids examined. Pea mutants deficient in gibberellins, DELLA proteins and brassinosteroids are used to determine whether fungal colonization is altered by the level of these hormones or signalling compounds. Expression of genes activated during mycorrhizal colonization is also monitored. Arbuscular mycorrhizal colonization of pea roots is substantially increased in gibberellin-deficient na-1 mutants compared with wild-type plants. This is reversed by application of GA3. Mutant la cry-s, which lacks gibberellin signalling DELLA proteins, shows reduced colonization. These changes were parallelled by changes in the expression of genes associated with mycorrhizal colonization. The brassinosteroid-deficient lkb mutant showed no change in colonization. Biologically active gibberellins suppress arbuscule formation in pea roots, and DELLA proteins are essential for this response, indicating that this role occurs within the root cells.

Effects of light on protein patterns in gravitropically stimulated root caps of corn

NASA Technical Reports Server (NTRS)

Feldman, L. J.; Gildow, V.

1984-01-01

In certain cultivars of corn (Zea mays var. Merit), light stimulates gravitropic bending of the root by influencing events in the root cap. In this paper, we report on changes in root cap proteins which occur as a result of the light treatment and single out specific proteins as potentially having a role in mediating the gravitropic response. For this work, we have used root caps maintained aseptically in culture media supplemented with auxin. If auxin is deleted from the culture medium, the protein profiles observed following illumination differ from that seen in caps provided light while in auxin-supplemented media. We also report that several of the proteins for which synthesis is stimulated by light appear to turn over rapidly, usually within 0.5 hour of formation.

Regulation of phytochrome message abundance in root caps of maize

NASA Technical Reports Server (NTRS)

Johnson, E. M.; Pao, L. I.; Feldman, L. J.

1991-01-01

In many cultivars of maize (Zea mays L.) red light affects root development via the photomorphogenetic pigment phytochrome. The site of perception for the light is the root cap. In the maize cultivar Merit, we investigated phytochrome-mediated events in the cap. We established that the message encoded by the phyA1 gene was most abundant in dark-grown tissue and was asymmetrically distributed in the root cap, with greatest expression in the cells which make up the central columella core of the cap. Phytochrome message was negatively autoregulated in a specific region within the root cap. This autoregulation was sensitive to very-low-fluence red light, and thus was characterized as a phytochrome-mediated, very-low-fluence event. The kinetics of message reaccumulation in the dark were also examined and compared to the kinetics of the light requirement for root gravitropism in this cultivar. Similarly, the degree of autoregulation present in two other maize cultivars with different light requirements for gravitropic sensitivity was investigated. It appears that the Merit cultivar expresses a condition of hypersensitivity to phytochrome-mediated light regulation in root tissues. We conclude that phytochrome regulates many activities within the cap, but the degree to which these activities share common phytochrome-mediated steps is not known.

Co-inoculation of a Pea Core-Collection with Diverse Rhizobial Strains Shows Competitiveness for Nodulation and Efficiency of Nitrogen Fixation Are Distinct traits in the Interaction

PubMed Central

Bourion, Virginie; Heulin-Gotty, Karine; Aubert, Véronique; Tisseyre, Pierre; Chabert-Martinello, Marianne; Pervent, Marjorie; Delaitre, Catherine; Vile, Denis; Siol, Mathieu; Duc, Gérard; Brunel, Brigitte; Burstin, Judith; Lepetit, Marc

2018-01-01

Pea forms symbiotic nodules with Rhizobium leguminosarum sv. viciae (Rlv). In the field, pea roots can be exposed to multiple compatible Rlv strains. Little is known about the mechanisms underlying the competitiveness for nodulation of Rlv strains and the ability of pea to choose between diverse compatible Rlv strains. The variability of pea-Rlv partner choice was investigated by co-inoculation with a mixture of five diverse Rlv strains of a 104-pea collection representative of the variability encountered in the genus Pisum. The nitrogen fixation efficiency conferred by each strain was determined in additional mono-inoculation experiments on a subset of 18 pea lines displaying contrasted Rlv choice. Differences in Rlv choice were observed within the pea collection according to their genetic or geographical diversities. The competitiveness for nodulation of a given pea-Rlv association evaluated in the multi-inoculated experiment was poorly correlated with its nitrogen fixation efficiency determined in mono-inoculation. Both plant and bacterial genetic determinants contribute to pea-Rlv partner choice. No evidence was found for co-selection of competitiveness for nodulation and nitrogen fixation efficiency. Plant and inoculant for an improved symbiotic association in the field must be selected not only on nitrogen fixation efficiency but also for competitiveness for nodulation. PMID:29367857

Co-inoculation of a Pea Core-Collection with Diverse Rhizobial Strains Shows Competitiveness for Nodulation and Efficiency of Nitrogen Fixation Are Distinct traits in the Interaction.

PubMed

Bourion, Virginie; Heulin-Gotty, Karine; Aubert, Véronique; Tisseyre, Pierre; Chabert-Martinello, Marianne; Pervent, Marjorie; Delaitre, Catherine; Vile, Denis; Siol, Mathieu; Duc, Gérard; Brunel, Brigitte; Burstin, Judith; Lepetit, Marc

2017-01-01

Pea forms symbiotic nodules with Rhizobium leguminosarum sv. viciae (Rlv). In the field, pea roots can be exposed to multiple compatible Rlv strains. Little is known about the mechanisms underlying the competitiveness for nodulation of Rlv strains and the ability of pea to choose between diverse compatible Rlv strains. The variability of pea-Rlv partner choice was investigated by co-inoculation with a mixture of five diverse Rlv strains of a 104-pea collection representative of the variability encountered in the genus Pisum . The nitrogen fixation efficiency conferred by each strain was determined in additional mono-inoculation experiments on a subset of 18 pea lines displaying contrasted Rlv choice. Differences in Rlv choice were observed within the pea collection according to their genetic or geographical diversities. The competitiveness for nodulation of a given pea-Rlv association evaluated in the multi-inoculated experiment was poorly correlated with its nitrogen fixation efficiency determined in mono-inoculation. Both plant and bacterial genetic determinants contribute to pea-Rlv partner choice. No evidence was found for co-selection of competitiveness for nodulation and nitrogen fixation efficiency. Plant and inoculant for an improved symbiotic association in the field must be selected not only on nitrogen fixation efficiency but also for competitiveness for nodulation.

Transposon tagging and the study of root development in Arabidopsis

NASA Technical Reports Server (NTRS)

Tsugeki, R.; Olson, M. L.; Fedoroff, N. V.

1998-01-01

The maize Ac-Ds transposable element family has been used as the basis of transposon mutagenesis systems that function in a variety of plants, including Arabidopsis. We have developed modified transposons and methods which simplify the detection, cloning and analysis of insertion mutations. We have identified and are analyzing two plant lines in which genes expressed either in the root cap cells or in the quiescent cells, cortex/endodermal initial cells and columella cells of the root cap have been tagged with a transposon carrying a reporter gene. A gene expressed in root cap cells tagged with an enhancer-trap Ds was isolated and its corresponding EST cDNA was identified. Nucleotide and deduced amino acid sequences of the gene show no significant similarity to other genes in the database. Genetic ablation experiments have been done by fusing a root cap-specific promoter to the diphtheria toxin A-chain gene and introducing the fusion construct into Arabidopsis plants. We find that in addition to eliminating gravitropism, root cap ablation inhibits elongation of roots by lowering root meristematic activities.

Effects of cations on hormone transport in primary roots of Zea mays

NASA Technical Reports Server (NTRS)

Hasenstein, K. H.; Evans, M. L.

1988-01-01

We examined the influence of aluminum and calcium (and certain other cations) on hormone transport in corn roots. When aluminum was applied unilaterally to the caps of 15 mm apical root sections the roots curved strongly away from the aluminum. When aluminum was applied unilaterally to the cap and 3H-indole-3-acetic acid was applied to the basal cut surface twice as much radioactivity (assumed to be IAA) accumulated on the concave side of the curved root as on the convex side. Auxin transport in the apical region of intact roots was preferentially basipetal, with a polarity (basipetal transport divided by acropetal transport) of 6.3. In decapped 5 mm apical root segments, auxin transport was acropetally polar (polarity = 0.63). Application of aluminum to the root cap strongly promoted acropetal transport of auxin reducing polarity from 6.3 to 2.1. Application of calcium to the root cap enhanced basipetal movement of auxin, increasing polarity from 6.3 to 7.6. Application of the calcium chelator, ethylene-glycol-bis-(beta-aminoethylether)-N,N,N',N'-tetraacetic acid, greatly decreased basipetal auxin movement, reducing polarity from 6.3 to 3.7. Transport of label after application of tritiated abscisic acid showed no polarity and was not affected by calcium or aluminum. The results indicate that the root cap is particularly important in maintaining basipetal polarity of auxin transport in primary roots of corn. The induction of root curvature by unilateral application of aluminum or calcium to root caps is likely to result from localized effects of these ions on auxin transport. The findings are discussed relative to the possible role of calcium redistribution in the gravitropic curvature of roots and the possibility of calmodulin involvement in the action of calcium and aluminum on auxin transport.

Mapping the functional roles of cap cells in the response of Arabidopsis primary roots to gravity

NASA Technical Reports Server (NTRS)

Blancaflor, E. B.; Fasano, J. M.; Gilroy, S.; Evans, M. L. (Principal Investigator)

1998-01-01

The cap is widely accepted to be the site of gravity sensing in roots because removal of the cap abolishes root curvature. Circumstantial evidence favors the columella cells as the gravisensory cells because amyloplasts (and often other cellular components) are polarized with respect to the gravity vector. However, there has been no functional confirmation of their role. To address this problem, we used laser ablation to remove defined cells in the cap of Arabidopsis primary roots and quantified the response of the roots to gravity using three parameters: time course of curvature, presentation time, and deviation from vertical growth. Ablation of the peripheral cap cells and tip cells did not alter root curvature. Ablation of the innermost columella cells caused the strongest inhibitory effect on root curvature without affecting growth rates. Many of these roots deviated significantly from vertical growth and had a presentation time 6-fold longer than the controls. Among the two inner columella stories, the central cells of story 2 contributed the most to root gravitropism. These cells also exhibited the largest amyloplast sedimentation velocities. Therefore, these results are consistent with the starch-statolith sedimentation hypothesis for gravity sensing.

Changes in root cap pH are required for the gravity response of the Arabidopsis root

NASA Technical Reports Server (NTRS)

Fasano, J. M.; Swanson, S. J.; Blancaflor, E. B.; Dowd, P. E.; Kao, T. H.; Gilroy, S.

2001-01-01

Although the columella cells of the root cap have been identified as the site of gravity perception, the cellular events that mediate gravity signaling remain poorly understood. To determine if cytoplasmic and/or wall pH mediates the initial stages of root gravitropism, we combined a novel cell wall pH sensor (a cellulose binding domain peptide-Oregon green conjugate) and a cytoplasmic pH sensor (plants expressing pH-sensitive green fluorescent protein) to monitor pH dynamics throughout the graviresponding Arabidopsis root. The root cap apoplast acidified from pH 5.5 to 4.5 within 2 min of gravistimulation. Concomitantly, cytoplasmic pH increased in columella cells from 7.2 to 7.6 but was unchanged elsewhere in the root. These changes in cap pH preceded detectable tropic growth or growth-related pH changes in the elongation zone cell wall by 10 min. Altering the gravity-related columella cytoplasmic pH shift with caged protons delayed the gravitropic response. Together, these results suggest that alterations in root cap pH likely are involved in the initial events that mediate root gravity perception or signal transduction.

Light-regulated protein and mRNA synthesis in root caps of maize

NASA Technical Reports Server (NTRS)

Feldman, L. J.; Piechulla, B.; Sun, P. S.

1988-01-01

Illumination of maize roots initiates changes in mRNA levels and in the activities of proteins within the root cap. Using Northern analysis we showed a 5-6 fold increase in the levels of three specific mRNAs and a 14-fold increase in plastid mRNA. This increase is rapid, occurring within 30 minutes of illumination. With prolonged periods of darkness following illumination, messages return to levels observed in dark, control caps. For two species of mRNA illumination results in a reduction in message levels. Light-stimulated increases in the levels of specific mRNAs are proportionally greater than are increases in the activities of corresponding proteins. We suggest that the light-stimulated increase in protein activity in root caps may be preceded by and occur as a consequence of enhanced levels of mRNA. Our work suggests that photomorphogenesis in roots could involve changes in the levels of a wide variety of mRNAs within the root cap.

Lipid Peroxidation Is an Early Symptom Triggered by Aluminum, But Not the Primary Cause of Elongation Inhibition in Pea Roots1

PubMed Central

Yamamoto, Yoko; Kobayashi, Yukiko; Matsumoto, Hideaki

2001-01-01

Pea (Pisum sativum) roots were treated with aluminum in a calcium solution, and lipid peroxidation was investigated histochemically and biochemically, as well as other events caused by aluminum exposure. Histochemical stainings were observed to distribute similarly on the entire surface of the root apex for three events (aluminum accumulation, lipid peroxidation, and callose production), but the loss of plasma membrane integrity (detected by Evans blue uptake) was localized exclusively at the periphery of the cracks on the surface of root apex. The enhancement of four events (aluminum accumulation, lipid peroxidation, callose production, and root elongation inhibition) displayed similar aluminum dose dependencies and occurred by 4 h. The loss of membrane integrity, however, was enhanced at lower aluminum concentrations and after longer aluminum exposure (8 h). The addition of butylated hydroxyanisole (a lipophilic antioxidant) during aluminum treatment completely prevented lipid peroxidation and callose production by 40%, but did not prevent or slow the other events. Thus lipid peroxidation is a relatively early symptom induced by the accumulation of aluminum and appears to cause, in part, callose production, but not the root elongation inhibition; by comparison, the loss of plasma membrane integrity is a relatively late symptom caused by cracks in the root due to the inhibition of root elongation. PMID:11154329

Plant Chemiluminescence

PubMed Central

Abeles, Fred B.; Leather, Gerald R.; Forrence, Leonard E.

1978-01-01

Light production by plants was confirmed by measuring chemiluminescence from root and stem tissue of peas (Pisum sativum), beans (Phaseolus vulgaris), and corn (Zea mays) in a modified scintillation spectrophotometer. Chemiluminescence was inhibited by treating pea roots with boiling ethanol or by placing them in a N2 gas phase. Chemiluminescence was increased by an O2 gas phase or by the addition of luminol. NaN3 and NaCN blocked both in vitro and in vivo chemiluminescence. It is postulated that the source of light is the hydrogen peroxide-peroxidase enzyme system. It is known that this system is responsible for chemiluminescence in leukocytes and it seems likely that a similar system occurs in plants. PMID:16660587

Influence of microgravity on cellular differentiation in root caps of Zea mays

NASA Technical Reports Server (NTRS)

Moore, R.; Fondren, W. M.; McClelen, C. E.; Wang, C. L.

1987-01-01

We launched imbibed seeds of Zea mays into outer space aboard the space shuttle Columbia to determine the influence of microgravity on cellular differentiation in root caps. The influence of microgravity varied with different stages of cellular differentiation. Overall, microgravity tended to 1) increase relative volumes of hyaloplasm and lipid bodies, 2) decrease the relative volumes of plastids, mitochondria, dictyosomes, and the vacuome, and 3) exert no influence on the relative volume of nuclei in cells comprising the root cap. The reduced allocation of dictyosomal volume in peripheral cells of flight-grown seedlings correlated positively with their secretion of significantly less mucilage than peripheral cells of Earth-grown seedlings. These results indicate that 1) microgravity alters the patterns of cellular differentiation and structures of all cell types comprising the root cap, and 2) the influence of microgravity on cellular differentiation in root caps of Zea mays is organelle specific.

Free-air CO2 enrichment (FACE) reduces the inhibitory effect of soil nitrate on N2 fixation of Pisum sativum.

PubMed

Butterly, Clayton R; Armstrong, Roger; Chen, Deli; Tang, Caixian

2016-01-01

Additional carbohydrate supply resulting from enhanced photosynthesis under predicted future elevated CO2 is likely to increase symbiotic nitrogen (N) fixation in legumes. This study examined the interactive effects of atmospheric CO2 and nitrate (NO3(-)) concentration on the growth, nodulation and N fixation of field pea (Pisum sativum) in a semi-arid cropping system. Field pea was grown for 15 weeks in a Vertosol containing 5, 25, 50 or 90 mg NO3(-)-N kg(-1) under either ambient CO2 (aCO2; 390 ppm) or elevated CO2 (eCO2; 550 ppm) using free-air CO2 enrichment (SoilFACE). Under aCO2, field pea biomass was significantly lower at 5 mg NO3(-)-N kg(-1) than at 90 mg NO3(-)-N kg(-1) soil. However, increasing the soil N level significantly reduced nodulation of lateral roots but not the primary root, and nodules were significantly smaller, with 85% less nodule mass in the 90 NO3(-)-N kg(-1) than in the 5 mg NO3(-)-N kg(-1) treatment, highlighting the inhibitory effects of NO3(-). Field pea grown under eCO2 had greater biomass (approx. 30%) than those grown under aCO2, and was not affected by N level. Overall, the inhibitory effects of NO3(-) on nodulation and nodule mass appeared to be reduced under eCO2 compared with aCO2, although the effects of CO2 on root growth were not significant. Elevated CO2 alleviated the inhibitory effect of soil NO3(-) on nodulation and N2 fixation and is likely to lead to greater total N content of field pea growing under future elevated CO2 environments. © The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

A morphometric analysis of cellular differentiation in caps of primary and lateral roots of Helianthus annuus

NASA Technical Reports Server (NTRS)

Moore, R.

1985-01-01

In order to determine if patterns of cell differentiation are similar in primary and lateral roots, I performed a morphometric analysis of the ultrastructure of calyptrogen, columella, and peripheral cells in primary and lateral roots of Helianthus annuus. Each cell type is characterized by a unique ultrastructure, and the ultrastructural changes characteristic of cellular differentiation in root caps are organelle specific. No major structural differences exist in the structures of the composite cell types, or in patterns of cell differentiation in caps of primary vs. lateral roots.

Ferritin accumulation and degradation in different organs of pea (Pisum sativum) during development.

PubMed Central

Lobreaux, S; Briat, J F

1991-01-01

Iron concentration and ferritin distribution have been determined in different organs of pea (Pisum sativum) during development under conditions of continuous iron supply from hydroponic cultures. No ferritin was detected in total protein extracts from roots or leaves. However, a transient iron accumulation in the roots, which corresponds to an increase in iron uptake, was observed when young fruits started to develop. Ferritin was detectable in total protein extracts of flowers and pods, and it accumulated in seeds. In seeds, the same relative amount of ferritin was detected in cotyledons and in the embryo axis. In cotyledons, ferritin and iron concentration decrease progressively during the first week of germination. Ferritin in the embryo axis was processed, and disappeared, during germination, within the first 4 days of radicle and epicotyl growth. This degradation of ferritin in vivo was marked by a shortening of a 28 kDa subunit, giving 26.5 and 25 kDa polypeptides, reminiscent of the radical damage occurring in pea seed ferritin during iron exchange in vitro [Laulhere, Laboure & Briat (1989) J. Biol. Chem. 264, 3629-3635]. Developmental control of iron concentration and ferritin distribution in different organs of pea is discussed. Images Fig. 4. Fig. 6. Fig. 7. PMID:2006922

Adenosine kinase modulates root gravitropism and cap morphogenesis in Arabidopsis.

PubMed

Young, Li-Sen; Harrison, Benjamin R; Narayana Murthy, U M; Moffatt, Barbara A; Gilroy, Simon; Masson, Patrick H

2006-10-01

Adenosine kinase (ADK) is a key enzyme that regulates intra- and extracellular levels of adenosine, thereby modulating methyltransferase reactions, production of polyamines and secondary compounds, and cell signaling in animals. Unfortunately, little is known about ADK's contribution to the regulation of plant growth and development. Here, we show that ADK is a modulator of root cap morphogenesis and gravitropism. Upon gravistimulation, soluble ADK levels and activity increase in the root tip. Mutation in one of two Arabidopsis (Arabidopsis thaliana) ADK genes, ADK1, results in cap morphogenesis defects, along with alterations in root sensitivity to gravistimulation and slower kinetics of root gravitropic curvature. The kinetics defect can be partially rescued by adding spermine to the growth medium, whereas the defects in cap morphogenesis and gravitropic sensitivity cannot. The root morphogenesis and gravitropism defects of adk1-1 are accompanied by altered expression of the PIN3 auxin efflux facilitator in the cap and decreased expression of the auxin-responsive DR5-GUS reporter. Furthermore, PIN3 fails to relocalize to the bottom membrane of statocytes upon gravistimulation. Consequently, adk1-1 roots cannot develop a lateral auxin gradient across the cap, necessary for the curvature response. Interestingly, adk1-1 does not affect gravity-induced cytoplasmic alkalinization of the root statocytes, suggesting either that ADK1 functions between cytoplasmic alkalinization and PIN3 relocalization in a linear pathway or that the pH and PIN3-relocalization responses to gravistimulation belong to distinct branches of the pathway. Our data are consistent with a role for ADK and the S-adenosyl-L-methionine pathway in the control of root gravitropism and cap morphogenesis.

Adenosine Kinase Modulates Root Gravitropism and Cap Morphogenesis in Arabidopsis1[W][OA

PubMed Central

Young, Li-Sen; Harrison, Benjamin R.; U.M., Narayana Murthy; Moffatt, Barbara A.; Gilroy, Simon; Masson, Patrick H.

2006-01-01

Adenosine kinase (ADK) is a key enzyme that regulates intra- and extracellular levels of adenosine, thereby modulating methyltransferase reactions, production of polyamines and secondary compounds, and cell signaling in animals. Unfortunately, little is known about ADK's contribution to the regulation of plant growth and development. Here, we show that ADK is a modulator of root cap morphogenesis and gravitropism. Upon gravistimulation, soluble ADK levels and activity increase in the root tip. Mutation in one of two Arabidopsis (Arabidopsis thaliana) ADK genes, ADK1, results in cap morphogenesis defects, along with alterations in root sensitivity to gravistimulation and slower kinetics of root gravitropic curvature. The kinetics defect can be partially rescued by adding spermine to the growth medium, whereas the defects in cap morphogenesis and gravitropic sensitivity cannot. The root morphogenesis and gravitropism defects of adk1-1 are accompanied by altered expression of the PIN3 auxin efflux facilitator in the cap and decreased expression of the auxin-responsive DR5-GUS reporter. Furthermore, PIN3 fails to relocalize to the bottom membrane of statocytes upon gravistimulation. Consequently, adk1-1 roots cannot develop a lateral auxin gradient across the cap, necessary for the curvature response. Interestingly, adk1-1 does not affect gravity-induced cytoplasmic alkalinization of the root statocytes, suggesting either that ADK1 functions between cytoplasmic alkalinization and PIN3 relocalization in a linear pathway or that the pH and PIN3-relocalization responses to gravistimulation belong to distinct branches of the pathway. Our data are consistent with a role for ADK and the S-adenosyl-l-methionine pathway in the control of root gravitropism and cap morphogenesis. PMID:16891550

Influence of plant root exudates, germ tube orientation and passive conidia transport on biological control of fusarium wilt by strains of nonpathogenic Fusarium oxysporum.

PubMed

Mandeel, Qaher A

2006-03-01

In earlier studies, biological control of Fusarium wilt of cucumber induced by Fusarium oxysporum f. sp. cucumerinum was demonstrated using nonpathogenic strains C5 and C14 of Fusarium oxysporum. Strain C14 induced resistance and competed for infection sites whether roots were wounded or intact, whereas strain C5 required wounds to achieve biocontrol. In the current work, additional attributes involved in enhanced resistance by nonpathogenic biocontrol agents strains to Fusarium wilt of cucumber and pea were further investigated. In pre-penetration assays, pathogenic formae specials exhibited a significantly higher percentage of spore germination in 4-day-old root exudates of cucumber and pea than nonpathogens. Also, strain C5 exhibited the lowest significant reduction in spore germination in contrast to strain C14 or control. One-day-old cucumber roots injected with strain C14 resulted in significant reduction in germ tube orientation towards the root surface, 48-96 h after inoculation with F. o. cucumerinum spores, whereas strain C5 induced significantly lower spore orientation of the pathogen and only at 72 and 96 h after inoculation. In post-penetration tests, passive transport of microconidia of pathogenic and nonpathogens in stems from base to apex were examined when severed plant roots were immersed in spore suspension. In repeated trials, strain C5, F. o. cucumerinum and F. o. pisi were consistently isolated from stem tissues of both cucumber and pea at increasing heights over a 17 days incubation period. Strain C14 however, was recovered at a maximum translocation distance of 4.6 cm at day 6 and later height of isolation significantly declined thereafter to 1.2 cm at day 17. In pea stem, the decline was even less. Significant induction of resistance to challenge inoculation by the pathogen in cucumber occurred 72 and 96 h after pre-inoculation with biocontrol agents. Nonetheless, strain C14 induced protection as early as 48 h and the maximum resistance was reached at 96 h. The presented data confirm the previous findings that attributes important for nonpathogenic fusaria to induce resistant are: rapid spore germination and orientation in response to root exudate; active root penetration and passive conidia transport in stem to initiate defence reaction without pathogenicity and enough lag period between induction and challenge inoculation. Strain C14 possesses all these qualifications and hence its ability to enhance host resistance is superior than strain C5.

Plant hormones in arbuscular mycorrhizal symbioses: an emerging role for gibberellins

PubMed Central

Foo, Eloise; Ross, John J.; Jones, William T.; Reid, James B.

2013-01-01

Background and Aims Arbuscular mycorrhizal symbioses are important for nutrient acquisition in >80 % of terrestrial plants. Recently there have been major breakthroughs in understanding the signals that regulate colonization by the fungus, but the roles of the known plant hormones are still emerging. Here our understanding of the roles of abscisic acid, ethylene, auxin, strigolactones, salicylic acid and jasmonic acid is discussed, and the roles of gibberellins and brassinosteroids examined. Methods Pea mutants deficient in gibberellins, DELLA proteins and brassinosteroids are used to determine whether fungal colonization is altered by the level of these hormones or signalling compounds. Expression of genes activated during mycorrhizal colonization is also monitored. Key Results Arbuscular mycorrhizal colonization of pea roots is substantially increased in gibberellin-deficient na-1 mutants compared with wild-type plants. This is reversed by application of GA3. Mutant la cry-s, which lacks gibberellin signalling DELLA proteins, shows reduced colonization. These changes were parallelled by changes in the expression of genes associated with mycorrhizal colonization. The brassinosteroid-deficient lkb mutant showed no change in colonization. Conclusions Biologically active gibberellins suppress arbuscule formation in pea roots, and DELLA proteins are essential for this response, indicating that this role occurs within the root cells. PMID:23508650

Impact of dyeing industry effluent on germination and growth of pea (Pisum sativum).

PubMed

Malaviya, Piyush; Hali, Rajesh; Sharma, Neeru

2012-11-01

Dye industry effluent was analyzed for physico-chemical characteristics and its impact on germination and growth behaviour of Pea (Pisum sativum). The 100% effluent showed high pH (10.3) and TDS (1088 mg l(-1)). The germination parameters included percent germination, delay index, speed of germination, peak value and germination period while growth parameters comprised of root and shoot length, root and shootweight, root-shoot ratio and number of stipules. The study showed the maximum values of positive germination parameters viz. speed of germination (7.85), peak value (3.28), germination index (123.87) and all growth parameters at 20% effluent concentration while the values of negative germination parameters viz. delay index (-0.14) and percent inhibition (-8.34) were found to be minimum at 20% effluent concentration. The study demonstrated that at lower concentrations the dyeing industry effluent caused a positive impact on germination and growth of Pisum sativum.

Correlations between gravitropic curvature and auxin movement across gravistimulated roots of Zea mays

NASA Technical Reports Server (NTRS)

Young, L. M.; Evans, M. L.; Hertel, R.

1990-01-01

We compared the kinetics of auxin redistribution across the caps of primary roots of 2-day-old maize (Zea mays, cv Merit) seedlings with the time course of gravitropic curvature. [3H] indoleacetic acid was applied to one side of the cap in an agar donor and radioactivity moving across the cap was collected in an agar receiver applied to the opposite side. Upon gravistimulation the roots first curved upward slightly, then returned to the horizontal and began curving downward, reaching a final angle of about 67 degrees. Movement of label across the caps of gravistimulated roots was asymmetric with preferential downward movement (ratio downward/upward = ca. 1.6, radioactivity collected during the 90 min following beginning of gravistimulation). There was a close correlation between the development of asymmetric auxin movement across the root cap and the rate of curvature, with both values increasing to a maximum and then declining as the roots approached the final angle of curvature. In roots preadapted to gravity (alternate brief stimulation on opposite flanks over a period of 1 hour) the initial phase of upward curvature was eliminated and downward bending began earlier than for controls. The correlation between asymmetric auxin movement and the kinetics of curvature also held in comparisons between control and preadapted roots. Both downward auxin transport asymmetry and downward curvature occurred earlier in preadapted roots than in controls. These findings are consistent with suggestions that the root cap is not only the site of perception but also the location of the initial redistribution of effectors that ultimately leads to curvature.

Quantification of phenylethylamine and p-tyramine in rat tissues using a new radioenzymatic assay

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hamburger, S.A.; Henry, D.P.

Phenylethylamine (PEA) and p-tyramine (p-tym) are biologically active aralkylamines that are found in a number of mammalian tissues, including brain and plasma. The investigation of the biological role of these substances has been hampered by the lack of accessible assay methodology. They have developed a new radioenzymatic assay using barley root tyramine N-methyltransferase and tritiated S-adenosylmethionine. The products formed by the reaction are isolated by TLC. The assay sensitivity was 2.1 and 1.0 pg/tube for PEA and p-tym, respectively. The concentration of PEA and p-tym was determined simultaneously in tissues from Sprague-Dawley rats (280 gm). Plasma PEA and p-tym weremore » 478 +/- 66 and 309 +/- 69 pg/ml, respectively. They conclude that this new procedure is applicable to all tissues examined in that all tissues contain both PEA and p-tym and that these amines are heterogeneously distributed in rat tissues.« less

Abscisic acid, xanthoxin and violaxanthin in the caps of gravistimulated maize roots

NASA Technical Reports Server (NTRS)

Feldman, L. J.; Arroyave, N. J.; Sun, P. S.

1985-01-01

The occurrence and distribution of abscisic acid (ABA), xanthoxin (Xa) and the carotenoid violaxanthin (Va) were investigated in root tips of maize (Zea mays L. cv. Merit). In roots grown in the dark, Va and ABA were present in relatively high amounts in the root cap and in low amounts in the adjacent terminal 1.5 mm of the root. Xanthoxin was present in equal concentrations in both regions. In roots exposed to light, the ABA distribution was reversed, with relatively low levels in the root cap and high levels in the adjacent 1.5-mm segment. Light also caused a decrease in Va in both regions of the root and an increase in Xa, especially in the cap. In the maize cultivar used for this work, light is necessary for gravitropic curving. This response occurs within the same time frame as the light-induced ABA redistribution as well as the changes in the levels of Va and Xa. These data are consistent with a role for ABA in root gravitropism and support the proposal that Xa may arise from the turnover of Va.

Cytochemical localization of calcium in cap cells of primary roots of Zea mays L

NASA Technical Reports Server (NTRS)

Moore, R.

1985-01-01

The cellular distribution of Ca in caps of primary roots of Zea mays was examined during the onset and early stages of gravicurvature to determine its possible role in root gravitropism. Staining becomes associated with the portion of the cell wall adjacent to the distal end of the cell after five minutes, and persists throughout the onset of gravicurvature. The outermost peripheral cells of roots oriented horizontally and vertically secrete Ca through plasmodesmata-like channels in their cell walls. Data suggest that Ca is not transported laterally through the columella tissue,but rather that the movement of Ca to the lower side of caps of horizontally-oriented roots is at least partially through and/or on the mucilage of the cap, and via an electrochemical gradient. An important role in root gravitropism is indicated for Ca secretion by peripheral cells.

How Roots Perceive and Respond to Gravity.

ERIC Educational Resources Information Center

Moore, Randy

1984-01-01

Discusses graviperception and gravitropism by plant roots. Indicates that graviperception occurs via sedimentation of amyloplasts in columella cells of the root cap and that the minimal graviresponsiveness of lateral roots may be due to the intensity of their caps to establish a concentration gradient of inhibitor(s) sufficient to affect…

Mechanisms of Hormone Action

PubMed Central

Abeles, F. B.; Ruth, J. M.; Forrence, L. E.; Leather, G. R.

1972-01-01

We observed no exchange between deuterated ethylene (C2D4) and the hydrogen of pea seedlings (Pisum sativum L. cv. Alaska). This suggests that bonding forces in which exchange could readily occur are not important in the physiological action of ethylene. Deuterated ethylene was just as effective as normal ethylene in inhibiting the growth of pea root sections. These results indicate that splitting carbon to hydrogen bonds did not occur during ethylene action. PMID:16658026

The involvement of glucose-6-phosphatase in mucilage secretion by root cap cells of Zea mays

NASA Technical Reports Server (NTRS)

Moore, R.; McClelen, C. E.

1985-01-01

In order to determine the involvement of glucose-6-phosphatase in mucilage secretion by root cap cells, we have cytochemically localized the enzyme in columella and peripheral cells of root caps of Zea mays. Glucose-6-phosphatase is associated with the plasmalemma and cell wall of columella cells. As columella cells differentiate into peripheral cells and begin to produce and secrete mucilage, glucose-6-phosphatase staining intensifies and becomes associated with the mucilage and, to a lesser extent, the cell wall. Cells being sloughed from the cap are characterized by glucose-6-phosphatase staining being associated with the vacuole and plasmalemma. These changes in enzyme localization during cellular differentiation in root caps suggest that glucose-6-phosphatase is involved in the production and/or secretion of mucilage by peripheral cells of Z. mays.

Phenetic, genetic diversity and symbiotic compatibility of rhizobial strains nodulating pigeon pea in Northern India.

PubMed

Arora, Naveen Kumar; Khare, Ekta; Singh, Sachin; Tewari, Sakshi

2018-01-01

Pigeon pea ( Cajanus cajan ) is one of the most important legumes grown in the northern province of Uttar Pradesh, India. However, its productively in Uttar Pradesh is lower than the average yield of adjoining states. During the course of the present study, a survey of pigeon pea growing agricultural fields was carried out and it was found that 80% of plants were inadequately nodulated. The study was aimed to evaluate the pigeon pea symbiotic compatibility and nodulation efficiency of root nodulating bacteria isolated from various legumes, and to explore the phenetic and genetic diversity of rhizobial population nodulating pigeon pea growing in fields of Uttar Pradesh. Amongst all the 96 isolates, 40 isolates showed nodulation in pigeon pea. These 40 isolates were further characterized by phenotypic, biochemical and physiological tests. Intrinsic antibiotic resistance pattern was taken to generate similarity matrix revealing 10 phenons. The study shows that most of the isolates nodulating pigeon pea in this region were rapid growers. The dendrogram generated using the NTSYSpc software grouped RAPD patterns into 19 clusters. The high degree of phenetic and genetic diversity encountered is probably because of a history of mixed cropping of legumes. The assessment of diversity is a very important tool and can be used to improve the nodulation and quality of pigeon pea crop. It is also concluded that difference between phenetic and RAPD clustering pattern is an indication that rhizobial diversity of pigeon pea is not as yet completely understood and settled.

A Receptor-Like Kinase Mediates Ammonium Homeostasis and Is Important for the Polar Growth of Root Hairs in Arabidopsis[W

PubMed Central

Bai, Ling; Ma, Xiaonan; Zhang, Guozeng; Song, Shufei; Zhou, Yun; Gao, Lijie; Miao, Yuchen; Song, Chun-Peng

2014-01-01

Ammonium (NH4+) is both a necessary nutrient and an important signal in plants, but can be toxic in excess. Ammonium sensing and regulatory mechanisms in plant cells have not been fully elucidated. To decipher the complex network of NH4+ signaling, we analyzed [Ca2+]cyt-associated protein kinase (CAP) genes, which encode signaling components that undergo marked changes in transcription levels in response to various stressors. We demonstrated that CAP1, a tonoplast-localized receptor-like kinase, regulates root hair tip growth by maintaining cytoplasmic Ca2+ gradients. A CAP1 knockout mutant (cap1-1) produced elevated levels of cytoplasmic NH4+. Furthermore, root hair growth of cap1-1 was inhibited on Murashige and Skoog medium, but NH4+ depletion reestablished the Ca2+ gradient necessary for normal growth. The lower net NH4+ influx across the vacuolar membrane and relatively alkaline cytosolic pH of cap1-1 root hairs implied that mutation of CAP1 increased NH4+ accumulation in the cytoplasm. Furthermore, CAP1 functionally complemented the npr1 (nitrogen permease reactivator protein) kinase yeast mutant, which is defective in high-affinity NH4+ uptake via MEP2 (methylammonium permease 2), distinguishing CAP1 as a cytosolic modulator of NH4+ levels that participates in NH4+ homeostasis-regulated root hair growth by modulating tip-focused cytoplasmic Ca2+ gradients. PMID:24769480

Protein and carotenoid synthesis and turnover in gravistimulated root caps

NASA Technical Reports Server (NTRS)

Feldman, L. J.

1984-01-01

In certain cultivars of corn gravitropic bending occurs only after the root cap, the site of gravity perception, is exposed to light. Light appears to trigger or to remove some block in the gravity translation process. Using light sensitive cultivars of corn, it was shown that light affects various processes in the cap. The roles of these light-induced processes in gravitropic bending in roots were studied.

Reactive Oxygene Species and Thioredoxin Activity in Plants at Development of Hypergravity and Oxidative Stresses

NASA Astrophysics Data System (ADS)

Jadko, Sergiy

Early increasing of reactive oxygen species (ROS) content, including H2O2, occurs in plant cells under various impacts and than these ROS can function as signaling molecules in starting of cell stress responses. At the same time thioredoxins (TR) are significant ROS and H2O2 sensors and transmitters to activation of various redox sensitive proteins, transcription factors and MAP kinases. This study was aimed to investigate early increasing of ROS and H2O2 contents and TR activity in the pea roots and in tissue culture under hypergravity and oxidative stresses. Pea roots of 3-5 days old seedlings and 12-14 days old tissue culture of Arabidopsis thaliana were studied. The pea seedlings were grown on wet filter paper and the tissue culture was grown on MS medium in dark conditions under 24oC. Hypergravity stress was induced by centrifugation at 10 and 15 g. Chemiluminescence (ChL) intensity for ROS concentration, H2O2 content and TR activity were determined. All experiments were repeated by 3-5 times. Early and reliable increasing of ChL intensity and H2O2 contents in the pea roots and in the tissue culture took place under hypergravity and oxidative stresses to 30, 60 and 90 min. At the same time TR activity increased on 11 and 19 percents only to 60 and 90 min. Thus under hypergravity and oxidative stresses in both investigated plants take place early increasing of ROS and H2O2 contents which as second messengers lead to increasing of TR activity with creating of ROS-TR stress signaling pathway.

Liming can decrease legume crop yield and leaf gas exchange by enhancing root to shoot ABA signalling

PubMed Central

Rothwell, Shane A.; Elphinstone, E. David; Dodd, Ian C.

2015-01-01

To meet future requirements for food production, sustainable intensive agricultural systems need to optimize nutrient availability to maximize yield, traditionally achieved by maintaining soil pH within an optimal range (6–6.5) by applying lime (calcium carbonate). However, a field trial that applied recommended liming rates to a sandy loam soil (increasing soil pH from 5.5 to 6.2) decreased pod yield of field bean (Vicia faba L. cv. Fuego) by ~30%. Subsequent pot trials, with liming that raised soil pH to 6.3–6.7, reduced stomatal conductance (g s) by 63, 26, and 59% in V. faba, bean (Phaseolus vulgaris), and pea (Pisum sativum), respectively. Furthermore, liming reduced shoot dry biomass by 16–24% in these species. Ionomic analysis of root xylem sap and leaf tissue revealed a decrease in phosphorus concentration that was correlated with decreased g s: both reductions were partially reversed by adding superphosphate fertilizer. Further analysis of pea suggests that leaf gas exchange was reduced by a systemic increase (roots, xylem sap, and leaves) in the phytohormone abscisic acid (ABA) in response to lime-induced suboptimal plant phosphorus concentrations. Supplying synthetic ABA via the transpiration stream to detached pea leaves, at the same xylem sap concentrations induced by liming, decreased transpiration. Furthermore, the g s of the ABA-deficient mutant pea wilty was unresponsive to liming, apparently confirming that ABA mediates some responses to low phosphorus availability caused by liming. This research provides a detailed mechanistic understanding of the physiological processes by which lime application can limit crop yields, and questions the suitability of current liming recommendations. PMID:25740925

Effect of metal-tolerant plant growth-promoting Rhizobium on the performance of pea grown in metal-amended soil.

PubMed

Wani, Parvaze Ahmad; Khan, Md Saghir; Zaidi, Almas

2008-07-01

The nickel- and zinc-tolerant plant growth-promoting (PGP) Rhizobium sp. RP5 was isolated from nodules of pea, grown in metal-contaminated Indian soils. The PGP potentials of strain RP5 was assessed under in vitro conditions. Strain RP5 displayed a high level of tolerance to nickel (350 microg ml(-1)) and zinc (1500 microg ml(-1)) and showed PGP activity under in vitro conditions. The PGP activity of this strain was further assessed with increasing concentrations of nickel and zinc, using pea as a test crop. The bio-inoculant enhanced the dry matter, nodule numbers, root N, shoot N, leghemoglobin, seed yield, and grain protein (GP) by 19%, 23%, 26%, 47%, 112%, 26%, and 8%, respectively, at 290 mg Ni kg(-1) while at 4890 mg Zn kg(-1) soil, it increased the dry matter, nodule numbers, leghemoglobin, seed yield, GP, and root and shoot N by 18%, 23%, 78%, 26%, 7%, 25%, and 42%, respectively, compared to plants grown in soil amended with metal only. The bio-inoculant increased the glutathione reductase activity of roots and nodules by 46% and 65% at 580 mg Ni kg(-1) and 47% and 54% at 9780 mg Zn kg(-1) soil, respectively, compared to uninoculated plants. The inoculated strain decreased the concentration of nickel and zinc in plant organs. The intrinsic abilities of nitrogen fixation, growth promotion, and the ability to reduce the toxicity of nickel and zinc of the tested strain could be of practical importance in augmenting the growth and yield of pea, in nickel- and zinc-polluted soils.

How roots perceive and respond to gravity

NASA Technical Reports Server (NTRS)

Moore, R.; Evans, M. L.

1986-01-01

Graviperception by plant roots is believed to occur via the sedimentation of amyloplasts in columella cells of the root cap. This physical stimulus results in an accumulation of calcium on the lower side of the cap, which in turn induces gravicurvature. In this paper we present a model for root gravitropism integrating gravity-induced changes in electrical potential, cytochemical localization of calcium in cells of gravistimulated roots, and the interdependence of calcium and auxin movement. Key features of the model are that 1) gravity-induced redistribution of calcium is an early event in the transduction mechanism, and 2) apoplastic movement of calcium through the root-cap mucilage may be an important component of the pathway for calcium movement.

The tropic response of plant roots to oxygen: oxytropism in Pisum sativum L

NASA Technical Reports Server (NTRS)

Porterfield, D. M.; Musgrave, M. E.

1998-01-01

Plant roots are known to orient growth through the soil by gravitropism, hydrotropism, and thigmotropism. Recent observations of plant roots that developed in a microgravity environment in space suggested that plant roots may also orient their growth toward oxygen (oxytropism). Using garden pea (Pisum sativum L. cv. Weibul's Apollo) and an agravitropic mutant (cv. Ageotropum), root oxytropism was studied in the controlled environment of a microrhizotron. A series of channels in the microrhizotron allowed establishment of an oxygen gradient of 0.8 mmol mol-1 mm-1. Curvature of seedling roots was determined prior to freezing the roots for subsequent spectrophotometric determinations of alcohol dehydrogenase activity. Oxytropic curvature was observed all along the gradient in both cultivars of pea. The normal gravitropic cultivar showed a maximal curvature of 45 degrees after 48 h, while the agravitropic mutant curved to 90 degrees. In each cultivar, the amount of curvature declined as the oxygen concentration decreased, and was linearly related to the root elongation rate. Since oxytropic curvature occurred in roots exposed to oxygen concentrations that were not low enough to induce the hypoxically responsive protein alcohol dehydrogenase, we suspect that the oxygen sensor associated with oxytropism does not control the induction of hypoxic metabolism. Our results indicate that oxygen can play a critical role in determining root orientation as well as impacting root metabolic status. Oxytropism allows roots to avoid oxygen-deprived soil strata and may also be the basis of an auto-avoidance mechanism, decreasing the competition between roots for water and nutrients as well as oxygen.

Preliminary enrichment and separation of genistein and apigenin from extracts of pigeon pea roots by macroporous resins.

PubMed

Liu, Wei; Zhang, Su; Zu, Yuan-Gang; Fu, Yu-Jie; Ma, Wei; Zhang, Dong-Yang; Kong, Yu; Li, Xiao-Juan

2010-06-01

Enrichment and separation of genistein and apigenin from extracts of pigeon pea roots were studied using eleven macroporous resins with different physical and chemical properties. ADS-5 resin showed the maximum effectiveness among the tested resins. The solute affinity towards ADS-5 resin at different temperatures was described in terms of Langmuir and Freundlich isotherms, and the equilibrium experimental data were well-fitted to the two isotherms. In order to optimize the operating parameters for separating genistein and apigenin, dynamic adsorption and desorption tests were carried out. After one run treatment with ADS-5 resin, the contents of genistein and apigenin in the product were 9.36-fold and 11.09-fold increased with recovery yields of 89.78% and 93.41%, respectively. The process achieved easy and effective enrichment and separation of genistein and apigenin by using ADS-5 resin, and it is a promising basis for large-scale preparation of genistein and apigenin from pigeon pea or other plants extracts. (c) 2010 Elsevier Ltd. All rights reserved.

Two rhizobacterial strains, individually and in interactions with Rhizobium sp., enhance fusarial wilt control, growth, and yield in pigeon pea.

PubMed

Dutta, Swarnalee; Morang, Pranjal; Kumar S, Nishanth; Dileep Kumar, B S

2014-09-01

A Pseudomonas aeruginosa strain, RRLJ 04, and a Bacillus cereus strain, BS 03, were tested both individually and in combination with a Rhizobium strain, RH 2, for their ability to enhance plant growth and nodulation in pigeon pea (Cajanus cajan L.) under gnotobiotic, greenhouse and field conditions. Both of the rhizobacterial strains exhibited a positive effect on growth in terms of shoot height, root length, fresh and dry weight, nodulation and yield over the non-treated control. Co-inoculation of seeds with these strains and Rhizobium RH 2 also reduced the number of wilted plants, when grown in soil infested with Fusarium udum. Gnotobiotic studies confirmed that the suppression of wilt disease was due to the presence of the respective PGPR strains. Seed bacterization with drug-marked mutants of RRLJ 04 and BS 03 confirmed their ability to colonize and multiply along the roots. The results suggest that co-inoculation of these strains with Rhizobium strain RH 2 can be further exploited for enhanced growth, nodulation and yield in addition to control of fusarial wilt in pigeon pea.

Optimization of pre-sowing magnetic field doses through RSM in pea

NASA Astrophysics Data System (ADS)

Iqbal, M.; Ahmad, I.; Hussain, S. M.; Khera, R. A.; Bokhari, T. H.; Shehzad, M. A.

2013-09-01

Seed pre-sowing magnetic field treatment was reported to induce biochemical and physiological changes. In the present study, response surface methodology was used for deduction of optimal magnetic field doses. Improved growth and yield responses in the pea cultivar were achieved using a rotatable central composite design and multivariate data analysis. The growth parameters such as root and shoot fresh masses and lengths as well as yield were enhanced at a certain magnetic field level. The chlorophyll contents were also enhanced significantly vs. the control. The low magnetic field strength for longer duration of exposure/ high strength for shorter exposure were found to be optimal points for maximum responses in root fresh mass, chlorophyll `a' contents, and green pod yield/plant, respectively and a similar trend was observed for other measured parameters. The results indicate that the magnetic field pre-sowing seed treatment can be used practically to enhance the growth and yield in pea cultivar and response surface methodology was found an efficient experimental tool for optimization of the treatment level to obtain maximum response of interest.

A rapid method to increase the number of F₁ plants in pea (Pisum sativum) breeding programs.

PubMed

Espósito, M A; Almirón, P; Gatti, I; Cravero, V P; Anido, F S L; Cointry, E L

2012-08-16

In breeding programs, a large number of F₂ individuals are required to perform the selection process properly, but often few such plants are available. In order to obtain more F₂ seeds, it is necessary to multiply the F₁ plants. We developed a rapid, efficient and reproducible protocol for in vitro shoot regeneration and rooting of seeds using 6-benzylaminopurine. To optimize shoot regeneration, basic medium contained Murashige and Skoog (MS) salts with or without B5 Gamborg vitamins and different concentrations of 6-benzylaminopurine (25, 50 and 75 μM) using five genotypes. We found that modified MS (B5 vitamins + 25 μM 6-benzylaminopurine) is suitable for in vitro shoot regeneration of pea. Thirty-eight hybrid combinations were transferred onto selected medium to produce shoots that were used for root induction on MS medium supplemented with α-naphthalene-acetic acid. Elongated shoots were developed from all hybrid genotypes. This procedure can be used in pea breeding programs and will allow working with a large number of plants even when the F₁ plants produce few seeds.

Changes in root gravitropism, ultrastructure, and calcium balance of pea root statocytes induced by A23187

NASA Astrophysics Data System (ADS)

Belyavskaya, N.

The role for calcium in the regulation of a wide variety of cellular events in plants is well known. Calcium signaling has been implicated in plant gravitropism. A carboxylic acid antibiotic A23187 (calcimycin) has been widely used in biological studies since it can translocate calcium across membranes. Seedlings of Pisum sativum L. cv. Uladovsky germinated in a vertically oriented cylinder of moist filter paper soaked in water during 4.5 day had been treated with 10-5 M A23187 for 12 hr. Tips of primary roots of control and A23187-treated pea seedlings were fixed for electron microscopy and electron cytochemistry. Experiments with Pisum sativum 5- day seedlings placed horizontally for 4 h after treatment with 10 μM A23187 during 12 h found that the graviresponsiveness of their primary roots was lost completely (91 % of roots) or inhibited (24 +/- 6° in comparison with 88 +/- 8° in control). At ultrastructural level, there were observed distribution of amyloplasts around the nucleus, remarkable lengthening of statocytes, advanced vacuolization, changes in dictyosome structure, ER fragmentation, cell wall thinning in A23187-treated statocytes. Cytochemical study has indicated that statocytes exposed to calcimycin have contained a number of Ca-pyroantimonate granules detected Ca 2 + ions in organelles and hyaloplasm (unlike the control ones). The deposits were mainly associated with the plasma membrane. Among organelles, mitochondria were notable for their ability to accumulate Ca 2 +. In amyloplasts, a fine precipitate was predominately located in their stroma and envelope lumens. In cell walls, deposits of the reaction product were observed along the periphery and in the median zone. Localization of electron-dense granules of lead phosphate, which indicated Ca 2 +- ATPase activities in pea statocytes exposed to A23187, was generally consistent with that in untreated roots. Apart from plasma membrane, chromatin, and nucleolus components, the cytochemical reaction product was found in mitochondrial cristae in contrast to control ones. The presence of the precipitate in other Ca 2 +-sequestered organelles was not determined. The data presented suggest that at the ultrastructural level, the effects of the Ca 2 + ionophore manifested in the loss of polarity in statocytes may be functionally related to systems that regulate the intracellular Ca 2 + homeostasis. It is evident that significant increase in Ca 2 + level in A23187-treated statocytes may cause a disbalance in the gravisensor system and/or calcium signaling and therefore to abolish gravitropism of pea roots.

Auxin Biosynthesis in Pea: Characterization of the Tryptamine Pathway1[W][OA

PubMed Central

Quittenden, Laura J.; Davies, Noel W.; Smith, Jason A.; Molesworth, Peter P.; Tivendale, Nathan D.; Ross, John J.

2009-01-01

One pathway leading to the bioactive auxin, indole-3-acetic acid (IAA), is known as the tryptamine pathway, which is suggested to proceed in the sequence: tryptophan (Trp), tryptamine, N-hydroxytryptamine, indole-3-acetaldoxime, indole-3-acetaldehyde (IAAld), IAA. Recently, this pathway has been characterized by the YUCCA genes in Arabidopsis (Arabidopsis thaliana) and their homologs in other species. YUCCA is thought to be responsible for the conversion of tryptamine to N-hydroxytryptamine. Here we complement the genetic findings with a compound-based approach in pea (Pisum sativum), detecting potential precursors by gas chromatography/tandem-mass spectrometry. In addition, we have synthesized deuterated forms of many of the intermediates involved, and have used them to quantify the endogenous compounds, and to investigate their metabolic fates. Trp, tryptamine, IAAld, indole-3-ethanol, and IAA were detected as endogenous constituents, whereas indole-3-acetaldoxime and one of its products, indole-3-acetonitrile, were not detected. Metabolism experiments indicated that the tryptamine pathway to IAA in pea roots proceeds in the sequence: Trp, tryptamine, IAAld, IAA, with indole-3-ethanol as a side-branch product of IAAld. N-hydroxytryptamine was not detected, but we cannot exclude that it is an intermediate between tryptamine and IAAld, nor can we rule out the possibility of a Trp-independent pathway operating in pea roots. PMID:19710233

The GIST Model for Selection and Modification of Scientific Research for the College Teaching Laboratory Based on Root Competition Investigations

ERIC Educational Resources Information Center

Elliott, Shannon Snyder

2007-01-01

The purpose of this study is to first develop an 8-week college teaching module based on root competition literature. The split-root technique is adapted for the teaching laboratory, and the Sugar Ann English pea (Pisum sativum var. Sugar Ann English) is selected as the species of interest prior to designing experiments, either original or…

The Effect of Weak Combined Magnetic Field on Root Gravitropism and a Role of Ca2+ Ions Therein

NASA Astrophysics Data System (ADS)

Kordyum, Elizabeth; Bogatina, Nina; Kondrachuk, A.

At present, magnetic fields of different types are widely used to study gravity sensing in plants. For instance, magnetic levitation of amyloplasts caused by high gradient magnetic field enables us to alter the effective gravity sensed by plant cells. For the first time we showed that a weak combined magnetic field (CMF), that is the sum of collinear permanent and alternating magnetic fields ( 0.5 gauss, 0-100 Hz), changes a cress and pea root positive gravitropic reaction on a negative one. This effect has the form of resonance and occurs at the frequency of cyclotron resonance of calcium ions. What is especially interesting is that under gravistimulation in the CMF, the displacement of amylopasts in the root cap statocytes is directed to the upper wall of a cell, i.e. in the direction opposite to the gravitational vector. The displacement of amyloplasts, which contain the abundance of free Ca2+ ions in the stroma, is accompanied by Ca2+ redistribution in the same direction, and increasing in the cytosol around amyloplasts near ten times in the CMF in comparison with the state magnetic field. Earlier, we also observed the Ca2+ accumulation in the upper site of a root curvature in the elongation zone in the CMF unlike a positive gravitropic reaction. Thus, it should be stressed that a root is bending in the same direction in which amyloplasts are displacing: downwards when gravitropism is positive and upwards when gravitropism is negative. The obtained data confirm the amyloplast statolithic function and give another striking demonstration of a leading role of Ca2+ ions in root gravitropism. But these data bring the question: what forces can promote amyloplast displacement against gravity? The possible explanation of the effect found is discussed. It is based on the ion cyclotron resonance in biosystems proposed by Liboff.. The original approach based on the use of a weak CMF may be helpful for understanding the mechanisms of plant gravisensing

Virus-induced plasma membrane aquaporin PsPIP2;1 silencing inhibits plant water transport of Pisum sativum.

PubMed

Song, Juanjuan; Ye, Guoliang; Qian, Zhengjiang; Ye, Qing

2016-12-01

Aquaporins (AQPs) are known to facilitate water transport across cell membranes, but the role of a single AQP in regulating plant water transport, particularly in plants other than Arabidopsis remains largely unexplored. In the present study, a virus-induced gene silencing (VIGS) technique was employed to suppress the expression of a specific plasma membrane aquaporin PsPIP2;1 of Pea plants (Pisum sativum), and subsequent effects of the gene suppression on root hydraulic conductivity (Lp r ), leaf hydraulic conductivity (K leaf ), root cell hydraulic conductivity (Lp rc ), and leaf cell hydraulic conductivity (Lp lc ) were investigated, using hydroponically grown Pea plants. Compared with control plants, VIGS-PsPIP2;1 plants displayed a significant suppression of PsPIP2;1 in both roots and leaves, while the expression of other four PIP isoforms (PsPIP1;1, PsPIP1;2, PsPIP2;2, and PsPIP2;3) that were simultaneously monitored were not altered. As a consequence, significant declines in water transport of VIGS-PsPIP2;1 plants were observed at both organ and cell levels, i.e., as compared to control plants, Lp r and K leaf were reduced by 29 %, and Lp rc and Lp lc were reduced by 20 and 29 %, respectively. Our results demonstrate that PsPIP2;1 alone contributes substantially to root and leaf water transport in Pea plants, and highlight VIGS a useful tool for investigating the role of a single AQP in regulating plant water transport.

Protein synthesis in geostimulated root caps

NASA Technical Reports Server (NTRS)

Feldman, L. J.

1982-01-01

A study is presented of the processes occurring in the root cap of corn which are requisite for the formation of root cap inhibitor and which can be triggered or modulated by both light and gravity. The results of this study indicate the importance of protein synthesis for light-induced gravitropic bending in roots. Root caps in which protein synthesis is prevented are unable to induce downward bending. This suggests that light acts by stimulating proteins which are necessary for the translation of the gravitropic stimulus into a growth response (downward bending). The turnover of protein with time was also examined in order to determine whether light acts by stimulating the synthesis of unique proteins required for downward growth. It is found that auxin in combination with light allows for the translation of the gravitropic stimulus into a growth response at least in part through the modification of protein synthesis. It is concluded that unique proteins are stimulated by light and are involved in promoting the downward growth in roots which are responding to gravity.

Synergistic Effects of a Calcium Phosphate/Fibronectin Coating on the Adhesion of Periodontal Ligament Stem Cells Onto Decellularized Dental Root Surfaces.

PubMed

Lee, Jung-Seok; Kim, Hyun-Suk; Park, So-Yon; Kim, Tae-Wan; Jung, Jae-Suk; Lee, Jong-Bin; Kim, Chang-Sung

2015-01-01

This study aimed to enhance the attachment of periodontal ligament stem cells (PDLSCs) onto the decellularized dental root surface using surface coating with fibronectin and/or calcium phosphate (CaP) and to evaluate the activity of PDLSCs attached to a coated dental root surface following tooth replantation. PDLSCs were isolated from five dogs, and the other dental roots were used as a scaffold for carrying PDLSCs and then assigned to one of four groups according to whether their surface was coated with CaP, fibronectin, CaP/fibronectin, or left uncoated (control). Fibronectin increased the adhesion of PDLSCs onto dental root surfaces compared to both the control and CaP-coated groups, and simultaneous surface coating with CaP and fibronectin significantly accelerated and increased PDLSC adhesion compared to the fibronectin-only group. On in vivo tooth replantation, functionally oriented periodontal new attachment was observed on the CaP/fibronectin-coated dental roots to which autologous PDLSCs had adhered, while in the control condition, dental root replantation was associated only with root resorption and ankylosis along the entire root length. CaP and fibronectin synergistically enhanced the attachment of PDLSCs onto dental root surfaces, and autologous PDLSCs could produce de novo periodontal new attachment in an experimental in vivo model.

In vitro regeneration through organogenesis and somatic embryogenesis in pigeon pea [ Cajanus cajan (L.) Millsp.] cv. JKR105.

PubMed

Krishna, Gaurav; Reddy, P Sairam; Ramteke, Pramod W; Rambabu, Pogiri; Sohrab, Sayed S; Rana, Debashis; Bhattacharya, Parthasarathi

2011-10-01

In vitro regeneration of pigeon pea through organogenesis and somatic embryogenesis was demonstrated with pigeon pea cv. JKR105. Embryonic axes explants of pigeon pea showed greater regeneration of shoot buds on 2.5 mg L(-1) 6-benzylaminopurine (BAP) in the medium, followed by further elongation at lower concentrations. Rooting of shoots was observed on half-strength Murashige and Skoog (MS) medium with 2 % sucrose and 0.5 mg L(-1) 3-indolebutyric acid (IBA). On the other hand, the regeneration of globular embryos from cotyledon explant was faster and greater with thidiazuron (TDZ) than BAP with sucrose as carbohydrate source. These globular embryos were maturated on MS medium with abscisic acid (ABA) and finally germinated on half-strength MS medium at lower concentrations of BAP. Comparison of regeneration pathways in pigeon pea cv. JKR105 showed that the turnover of successful establishment of plants achieved through organogenesis was more compared to somatic embryogenesis, despite the production of more embryos than shoot buds.

The role of calcium ions in cytological effects of hypogravity

NASA Astrophysics Data System (ADS)

Kordyum, E. L.; Belyavskaya, N. A.; Nedukha, E. M.; Palladina, T. A.; Tarasenko, V. A.

Electron-cytochemical and biochemical methods made it possible to reveal certain differences in ATPase activity stimulation by calcium ions in root apex cells of pea seedlings and moss protonema Funaria hygrometrica grown under stationary and slow clinostatic (2 rev/min) conditions. It was showed that under clinostatic conditions in comparison with the control variant the ATPase activity decreases in plasmalemma. The protein content in the plasmalemma fraction was also twice as low under these conditions. The root apex cells of the pea seedlings grown under spaceflight conditions were found to contain high concentrations of membrane-bound calcium. The data obtained are discussed in relation to problems of possible mechanisms of disturbance in calcium balance and the system of active calcium ion transport through plasmalemma under hypogravity.

The locations and amounts of endogenous ions and elements in the cap and elongating zone of horizontally oriented roots of Zea mays L.: an electron-probe EDS study

NASA Technical Reports Server (NTRS)

Moore, R.; Cameron, I. L.; Hunter, K. E.; Olmos, D.; Smith, N. K.

1987-01-01

We used quantitative electron-probe energy-dispersive x-ray microanalysis to localize endogenous Na, Cl, K, P, S, Mg and Ca in cryofixed and freeze-dried cryosections of the cap (i.e. the putative site of graviperception) and elongating zone (i.e. site of gravicurvature) of horizontally oriented roots of Zea mays. Ca, Na, Cl, K and Mg accumulate along the lower side of caps of horizontally oriented roots. The most dramatic asymmetries of these ions occur in the apoplast, especially the mucilage. We could not detect any significant differences in the concentrations of these ions in the central cytoplasm of columella cells along the upper and lower sides of caps of horizontally-oriented roots. However, the increased amounts of Na, Cl, K and Mg in the longitudinal walls of columella cells along the lower side of the cap suggest that these ions may move down through the columella tissue of horizontally-oriented roots. Ca also accumulates (largely in the mucilage) along the lower side of the elongating zone of horizontally-oriented roots, while Na, P, Cl and K tend to accumulate along the upper side of the elongating zone. Of these ions, only K increases in concentration in the cytoplasm and longitudinal walls of cortical cells in the upper vs lower sides of the elongating zone. These results indicate that (1) gravity-induced asymmetries of ions differ significantly in the cap and elongating zone of graviresponding roots, (2) Ca accumulates along the lower side of the cap and elongating zone of graviresponding roots, (3) increased growth of the upper side of the elongating zone of horizontally-oriented roots correlates positively with increased amounts of K in the cytoplasm and longitudinal walls of cortical cells, and (4) the apoplast (especially the mucilage) may be an important component of the pathway via which ions move in graviresponding rots of Zea mays. These results are discussed relative to mechanisms for graviperception and gravicurvature of roots.

Gas chromatography-mass spectrometry evidence for several endogenous auxins in pea seedling organs.

PubMed

Schneider, E A; Kazakoff, C W; Wightman, F

1985-08-01

Qualitative analysis by gas chromatography-mass spectrometry (GC-MS) of the auxins present in the root, cotyledons and epicotyl of 3-dold etiolated pea (Pisum sativum L., cv. Alaska) seedlings has shown that all three organs contain phenylacetic acid (PAA), 3-indoleacetic acid (IAA) and 4-chloro-3-indoleacetic acid (4Cl-IAA). In addition, 3-indolepropionic acid (IPA) was present in the root and 3-indolebutyric acid (IBA) was detected in both root and epicotyl. Phenylacetic acid, IAA and IPA were measured quantitatively in the three organs by GC-MS-single ion monitoring, using deuterated internal standards. Levels of IAA were found to range from 13 to 115 pmol g(-1) FW, while amounts of PAA were considerably higher (347-451 pmol g(-1) FW) and the level of IPA was quite low (5 pmol g(-1) FW). On a molar basis the PAA:IAA ratio in the whole seedling was approx. 15:1.

Enhanced gravitropism of roots with a disrupted cap actin cytoskeleton

NASA Technical Reports Server (NTRS)

Hou, Guichuan; Mohamalawari, Deepti R.; Blancaflor, Elison B.

2003-01-01

The actin cytoskeleton has been proposed to be a major player in plant gravitropism. However, understanding the role of actin in this process is far from complete. To address this problem, we conducted an analysis of the effect of Latrunculin B (Lat B), a potent actin-disrupting drug, on root gravitropism using various parameters that included detailed curvature kinetics, estimation of gravitropic sensitivity, and monitoring of curvature development after extended clinorotation. Lat B treatment resulted in a promotion of root curvature after a 90 degrees reorientation in three plant species tested. More significantly, the sensitivity of maize (Zea mays) roots to gravity was enhanced after actin disruption, as determined from a comparison of presentation time of Lat B-treated versus untreated roots. A short 10-min gravistimulus followed by extended rotation on a 1-rpm clinostat resulted in extensive gravitropic responses, manifested as curvature that often exceeded 90 degrees. Application of Lat B to the cap or elongation zone of maize roots resulted in the disruption of the actin cytoskeleton, which was confined to the area of localized Lat B application. Only roots with Lat B applied to the cap displayed the strong curvature responses after extended clinorotation. Our study demonstrates that disrupting the actin cytoskeleton in the cap leads to the persistence of a signal established by a previous gravistimulus. Therefore, actin could function in root gravitropism by providing a mechanism to regulate the proliferation of a gravitropic signal originating from the cap to allow the root to attain its correct orientation or set point angle.

The Influence of Lead on Generation of Signalling Molecules and Accumulation of Flavonoids in Pea Seedlings in Response to Pea Aphid Infestation.

PubMed

Woźniak, Agnieszka; Drzewiecka, Kinga; Kęsy, Jacek; Marczak, Łukasz; Narożna, Dorota; Grobela, Marcin; Motała, Rafał; Bocianowski, Jan; Morkunas, Iwona

2017-08-24

The aim of this study was to investigate the effect of an abiotic factor, i.e., lead at various concentrations (low causing a hormesis effect and causing high toxicity effects), on the generation of signalling molecules in pea ( Pisum sativum L. cv. Cysterski) seedlings and then during infestation by the pea aphid ( Acyrthosiphon pisum Harris). The second objective was to verify whether the presence of lead in pea seedling organs and induction of signalling pathways dependent on the concentration of this metal trigger defense responses to A. pisum . Therefore, the profile of flavonoids and expression levels of genes encoding enzymes of the flavonoid biosynthesis pathway (phenylalanine ammonialyase and chalcone synthase) were determined. A significant accumulation of total salicylic acid (TSA) and abscisic acid (ABA) was recorded in the roots and leaves of pea seedlings growing on lead-supplemented medium and next during infestation by aphids. Increased generation of these phytohormones strongly enhanced the biosynthesis of flavonoids, including a phytoalexin, pisatin. This research provides insights into the cross-talk between the abiotic (lead) and biotic factor (aphid infestation) on the level of the generation of signalling molecules and their role in the induction of flavonoid biosynthesis.

Comparison of in vivo dental pulp responses to capping with iRoot BP Plus and mineral trioxide aggregate.

PubMed

Shi, S; Bao, Z F; Liu, Y; Zhang, D D; Chen, X; Jiang, L M; Zhong, M

2016-02-01

To compare dental pulp responses to capping with iRoot BP Plus and mineral trioxide aggregate (MTA) in dogs. Pulps in 36 incisors of three 8-month-old beagle dogs were mechanically exposed and assigned to two experimental groups (iRoot BP Plus group and MTA group, n = 15 per group) and one control group (n = 6). Direct pulp capping was performed using either iRoot BP Plus or MTA. The animals were sacrificed 3 months later. Histological sections were stained with haematoxylin and eosin and categorized using a histologic scoring system. Statistical analysis was performed using the Mann-Whitney U-test, with the significance set at 0.05. The majority of specimens in both experimental groups were associated with complete calcified bridge formation and the absence of pulpal inflammation. There was no significant difference in pulp response to iRoot BP Plus or MTA after 3 months (P > 0.05). iRoot BP Plus and MTA had similar favourable results when used as pulp-capping agents. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Antineuropathic Profile of N-Palmitoylethanolamine in a Rat Model of Oxaliplatin-Induced Neurotoxicity

PubMed Central

Di Cesare Mannelli, Lorenzo; Pacini, Alessandra; Corti, Francesca; Boccella, Serena; Luongo, Livio; Esposito, Emanuela; Cuzzocrea, Salvatore; Maione, Sabatino; Calignano, Antonio; Ghelardini, Carla

2015-01-01

Neurotoxicity is a main side effect of the anticancer drug oxaliplatin. The development of a neuropathic syndrome impairs quality of life and potentially results in chemotherapy dose reductions and/or early discontinuation. In the complex pattern of molecular and morphological alterations induced by oxaliplatin in the nervous system, an important activation of glia has been preclinically evidenced. N-Palmitoylethanolamine (PEA) modulates glial cells and exerts antinociceptive effects in several animal models. In order to improve the therapeutic chances for chemotherapy-dependent neuropathy management, the role of PEA was investigated in a rat model of oxaliplatin-induced neuropathy (2.4 mg kg-1 daily, intraperitoneally). On day 21, a single administration of PEA (30 mg kg-1 i.p.) was able to reduce oxaliplatin-dependent pain induced by mechanical and thermal stimuli. The repeated treatment with PEA (30 mg kg-1 daily i.p. for 21 days, from the first oxaliplatin injection) prevented lowering of pain threshold as well as increased pain on suprathreshold stimulation. Ex vivo histological and molecular analysis of dorsal root ganglia, peripheral nerves and spinal cord highlighted neuroprotective effects and glia-activation prevention induced by PEA repeated administration. The protective effect of PEA resulted in the normalization of the electrophysiological activity of the spinal nociceptive neurons. Finally, PEA did not alter the oxaliplatin-induced mortality of the human colon cancer cell line HT-29. The efficacy of PEA in neuropathic pain control and in preventing nervous tissue alteration candidates this endogenous compound as disease modifying agent. These characteristics, joined to the safety profile, suggest the usefulness of PEA in chemotherapy-induced neuropathy. PMID:26039098

Physiological effects of nanoparticulate ZnO in green peas (Pisum sativum L.) cultivated in soil.

PubMed

Mukherjee, Arnab; Peralta-Videa, Jose R; Bandyopadhyay, Susmita; Rico, Cyren M; Zhao, Lijuan; Gardea-Torresdey, Jorge L

2014-01-01

The toxicological effects of zinc oxide nanoparticles (ZnO NPs) in plants are still largely unknown. In the present study, green pea (Pisum sativum L.) plants were treated with 0, 125, 250, and 500 mg kg(-1) of either ZnO NPs or bulk ZnO in organic matter enriched soil. Corresponding toxicological effects were measured on the basis of plant growth, chlorophyll production, Zn bioaccumulation, H2O2 generation, stress enzyme activity, and lipid peroxidation using different cellular, molecular, and biochemical approaches. Compared to control, all ZnO NP concentrations significantly increased (p ≤ 0.05) root elongation but no effects were observed in the stem. Whereas all bulk ZnO treatments significantly increased both root and stem length. After 25 days, chlorophyll in leaves decreased, compared to control, by ~61%, 67%, and 77% in plants treated with 125, 250, and 500 mg kg(-1) ZnO NPs, respectively. Similar results were found in bulk ZnO treated plants. At all ZnO NP concentrations CAT was significantly reduced in leaves (p ≤ 0.05), while APOX was reduced in both roots and leaves. In the case of bulk ZnO, APOX activity was down-regulated in the root and leaf and CAT was unaffected. At 500 mg kg(-1) treatment, the H2O2 in leaves increased by 61% with a twofold lipid peroxidation, which would be a predictive biomarker of nanotoxicity. This study could be pioneering in evaluating the phytotoxicity of ZnO NPs to green peas and can serve as a good indicator for measuring the effects on ZnO NPs in plants grown in organic matter enriched soil.

Protein tyrosine nitration in pea roots during development and senescence

PubMed Central

Corpas, Francisco J.

2013-01-01

Protein tyrosine nitration is a post-translational modification mediated by reactive nitrogen species (RNS) that is associated with nitro-oxidative damage. No information about this process is available in relation to higher plants during development and senescence. Using pea plants at different developmental stages (ranging from 8 to 71 days), tyrosine nitration in the main organs (roots, stems, leaves, flowers, and fruits) was analysed using immunological and proteomic approaches. In the roots of 71-day-old senescent plants, nitroproteome analysis enabled the identification a total of 16 nitrotyrosine-immunopositive proteins. Among the proteins identified, NADP-isocitrate dehydrogenase (ICDH), an enzyme involved in the carbon and nitrogen metabolism, redox regulation, and responses to oxidative stress, was selected to evaluate the effect of nitration. NADP-ICDH activity fell by 75% during senescence. Analysis showed that peroxynitrite inhibits recombinant cytosolic NADP-ICDH activity through a process of nitration. Of the 12 tyrosines present in this enzyme, mass spectrometric analysis of nitrated recombinant cytosolic NADP-ICDH enabled this study to identify the Tyr392 as exclusively nitrated by peroxynitrite. The data as a whole reveal that protein tyrosine nitration is a nitric oxide-derived PTM prevalent throughout root development and intensifies during senescence. PMID:23362300

Effects of abscisic acid and xanthoxin on elongation and gravitropism in primary roots of Zea mays

NASA Technical Reports Server (NTRS)

Lee, J. S.; Hasenstein, K. H.; Mulkey, T. J.; Yang, R. L.; Evans, M. L.

1990-01-01

We examined the involvement of abscisic acid (ABA) and xanthoxin (Xan) in maize root gravitropism by (1) testing the ability of ABA to allow positive gravitropism in dark-grown seedlings of the maize cultivar LG11, a cultivar known to require light for positive gravitropism of the primary root, (2) comparing curvature in roots in which half of the cap had been excised and replaced with agar containing either ABA or indole-3-acetic acid (IAA), (3) measuring gravitropism in roots of seedlings submerged in oxygenated solutions of ABA or IAA and (4) testing the effect of Xan on root elongation. Using a variety of methods of applying ABA to the root, we found that ABA did not cause horizontally-oriented primary roots of dark-grown seedlings to become positively gravitropic. Replacing half of the root cap of vertically oriented roots with an agar block containing ABA had little or no effect on curvature relative to that of controls in which the half cap was replaced by a plain agar block. Replacement of the removed half cap with IAA either canceled or reversed the curvature displayed by controls. When light-grown seedlings were submerged in ABA they responded strongly to gravistimulation while those in IAA did not. Xan (up to 0.1 mM) did not affect root elongation. The results indicate that ABA is not a likely mediator of root gravitropism and that the putative ABA precursor, Xan, lacks the appropriate growth-inhibiting properties to serve as a mediator of root gravitropism.

Touch modulates gravity sensing to regulate the growth of primary roots of Arabidopsis thaliana

NASA Technical Reports Server (NTRS)

Massa, Gioia D.; Gilroy, Simon

2003-01-01

Plants must sense and respond to diverse stimuli to optimize the architecture of their root system for water and nutrient scavenging and anchorage. We have therefore analyzed how information from two of these stimuli, touch and gravity, are integrated to direct root growth. In Arabidopsis thaliana, touch stimulation provided by a glass barrier placed across the direction of growth caused the root to form a step-like growth habit with bends forming in the central and later the distal elongation zones. This response led to the main root axis growing parallel to, but not touching the obstacle, whilst the root cap maintained contact with the barrier. Removal of the graviperceptive columella cells of the root cap using laser ablation reduced the bending response of the distal elongation zone. Similarly, although the roots of the gravisensing impaired pgm1-1 mutant grew along the barrier at the same average angle as wild-type, this angle became more variable with time. These observations imply a constant gravitropic re-setting of the root tip response to touch stimulation from the barrier. In wild-type plants, transient touch stimulation of root cap cells, but not other regions of the root, inhibited both subsequent gravitropic growth and amyloplast sedimentation in the columella. Taken together, these results suggest that the cells of the root cap sense touch stimuli and their subsequent signaling acts on the columella cells to modulate their graviresponse. This interaction of touch and gravity signaling would then direct root growth to avoid obstacles in the soil while generally maintaining downward growth.

Role of reactive oxygene species, peroxiredoxins and thioredoxins in reaction of plants to hypergravity and oxidative stresses

NASA Astrophysics Data System (ADS)

Jadko, Sergiy

Early increasing of reactive oxygen species (ROS) concentration, including H2O2, occur in plant cells under various impacts and these ROS can function as signaling molecules in starting of cell stress responses. Peroxiredoxins (Prx) and thioredoxins (Trx) are significant cell ROS/H2O2 sensors and transmitters. Prx besides its antioxidant activity, participate in creating of stress redox signals by destroying of H2O2 and reducing of Trx. Than these reduced Trx lead to activation of various redox sensitive proteins, transcription factors and MAP kinases. This study aimed to investigate early increasing of ROS and H2O2 contents and Prx and Trx activities in pea roots and arabidopsis tissue culture cells under hypergravity and oxidative stresses. Pea roots of 3-5 days old seedlings and 12 days old tissue culture of Arabidopsis thaliana from leaves were studied. Pea seedlings were grown on wet filter paper and the tissue culture was grown on MS medium in dark conditions under 24oC. Hypergravity stress was induced by centrifugation at 15 g. Chemiluminescence (ChL) intensity for ROS concentration, H2O2 content and Prx and Trx activities were determined. All experiments were repeated by 3-4 times. Early increasing of ChL intensity and H2O2 content in the pea roots and arabidopsis tissue culture cells took place under hypergravity and oxidative stresses and its were higher corresponding controls on average on 25, 21 and 17 percents to 30, 60 and 90 min. At the same time Prx and Trx activities increased on 7, 13 and 16 percents. Thus under hypergravity and oxidative stresses in both investigated plants take place early increasing of ROS and H2O2 contents which as second messengers can lead to ROS/H2O2-dependent increasing of Prx and Trx activities with creating of H2O2-Prx-Trx signaling pathway.

Automorphosis-like growth in etiolated pea seedlings is induced by the application of chemicals affecting perception of gravistimulation and its signal transduction

NASA Astrophysics Data System (ADS)

Miyamoto, Kensuke; Hoshino, Tomoki; Hitotsubashi, Reiko; Yamashita, Masamichi; Ueda, Junichi

Both microgravity conditions in space and simulated microgravity using a 3-dimensional clinostat resulted in: (1) automorphosis of etiolated pea seedlings, (2) epicotyls bending ca. 45° from the vertical line to the direction away from cotyledons, (3) inhibition of hook formation and (4) alternation of growth direction of roots. These facts indicate that the growth and development of etiolated pea seedlings on earth is under the influence of gravistimulation. Lanthanum and gadolinium ions, blockers of stretch-activated mechanosensitive ion channels, induced automorphosis-like epicotyl bending. Cantharidin, an inhibitor of protein phosphatase, also phenocopied automorphosis-like growth. On the other hand, cytochalasin B, cytochalasin D and brefeldin A did not induce automorphological epicotyl bending and inhibition of hook formation, although these compounds strikingly inhibited elongation of etiolated pea epicotyls. These results strongly suggest that stretch-activated mechanosensitive ion channels are involved in the perception of signals of gravistimuli in plants, and they are transduced by protein phosphorylation and dephosphorylation cascades by changing levels of calcium ions. Possible mechanisms to induce automorphosis-like growth in relation to gravity signals in etiolated pea seedlings are discussed.

Early root cap development and graviresponse in white clover (Trifolium repens) grown in space and on a two-axis clinostat

NASA Technical Reports Server (NTRS)

Smith, J. D.; Staehelin, L. A.; Todd, P.

1999-01-01

White clover (Trifolium repens) was germinated and grown in microgravity aboard the Space Shuttle (STS-60, 1994; STS-63, 1995), on Earth in stationary racks and in a slow-rotating two-axis clinostat. The objective of this study was to determine if normal root cap development and early plant gravity responses were dependent on gravitational cues. Seedlings were germinated in space and chemically fixed in orbit after 21, 40, and 72 h. Seedlings 96 h old were returned viable to earth. Germination and total seedling length were not dependent on gravity treatment. In space-flown seedlings, the number of cell stories in the root cap and the geometry of central columella cells did not differ from those of the Earth-grown seedlings. The root cap structure of clinorotated plants appeared similar to that of seedlings from microgravity, with the exception of three-day rotated plants, which displayed significant cellular damage in the columella region. Nuclear polarity did not depend on gravity; however, the positions of amyloplasts in the central columella cells were dependent on both the gravity treatment and the age of the seedlings. Seedlings from space, returned viable to earth, responded to horizontal stimulation as did 1 g controls, but seedlings rotated on the clinostat for the same duration had a reduced curvature response. This study demonstrates that initial root cap development is insensitive to either chronic clinorotation or microgravity. Soon after differentiation, however, clinorotation leads to loss of normal root cap structure and plant graviresponse while microgravity does not.

Graviresponsiveness and the Development of Columella Tissue in Primary and Lateral Roots of Ricinus communis1

PubMed Central

Moore, Randy; Pasieniuk, John

1984-01-01

Half-tipped primary and lateral roots of Ricinus communis cv Hale bend toward the side of the root on which the intact half-tip remains. Therefore, the minimal graviresponsiveness of lateral roots is not due to the inability of their caps to produce growth effectors (presumably inhibitors). The columella tissues of primary (i.e. graviresponsive) roots are (a) 4.30 times longer, (b) 2.95 times wider, (c) 37.4 times more voluminous, and (d) composed of 17.2 times more cells than those of lateral roots. The onset of positive gravitropism by lateral roots is positively correlated with a (a) 2.99-fold increase in length, (b) 2.63-fold increase in width, and (c) 20.7-fold increase in volume of their columella tissues. We propose that the minimal graviresponsiveness of lateral roots is due to the small size of their columella tissues, which results in their caps being unable to (a) establish a concentration gradient of the effector sufficient to induce gravicurvature and (b) produce as much of the effector as caps of graviresponsive roots. Images Fig. 1 PMID:11540818

Cytological and ultrastructural studies on root tissues

NASA Technical Reports Server (NTRS)

Slocum, R. D.; Gaynor, J. J.; Galston, A. W.

1984-01-01

The anatomy and fine structure of roots from oat and mung bean seedlings, grown under microgravity conditions for 8 days aboard the Space Shuttle, was examined and compared to that of roots from ground control plants grown under similar conditions. Roots from both sets of oat seedlings exhibited characteristic monocotyledonous tissue organization and normal ultrastructural features, except for cortex cell mitochondria, which exhibited a 'swollen' morphology. Various stages of cell division were observed in the meristematic tissues of oat roots. Ground control and flight-grown mung bean roots also showed normal tissue organization, but root cap cells in the flight-grown roots were collapsed and degraded in appearance, especially at the cap periphery. At the ultrastructural level, these cells exhibited a loss of organelle integrity and a highly-condensed cytoplasm. This latter observation perhaps suggests a differing tissue sensitivity for the two species to growth conditions employed in space flight. The basis for abnormal root cap cell development is not understood, but the loss of these putative gravity-sensing cells holds potential significance for long term plant growth orientation during space flight.

Semaphorin6A acts as a gate keeper between the central and the peripheral nervous system

PubMed Central

Mauti, Olivier; Domanitskaya, Elena; Andermatt, Irwin; Sadhu, Rejina; Stoeckli, Esther T

2007-01-01

Background During spinal cord development, expression of chicken SEMAPHORIN6A (SEMA6A) is almost exclusively found in the boundary caps at the ventral motor axon exit point and at the dorsal root entry site. The boundary cap cells are derived from a population of late migrating neural crest cells. They form a transient structure at the transition zone between the peripheral nervous system (PNS) and the central nervous system (CNS). Ablation of the boundary cap resulted in emigration of motoneurons from the ventral spinal cord along the ventral roots. Based on its very restricted expression in boundary cap cells, we tested for a role of Sema6A as a gate keeper between the CNS and the PNS. Results Downregulation of Sema6A in boundary cap cells by in ovo RNA interference resulted in motoneurons streaming out of the spinal cord along the ventral roots, and in the failure of dorsal roots to form and segregate properly. PlexinAs interact with class 6 semaphorins and are expressed by both motoneurons and sensory neurons. Knockdown of PlexinA1 reproduced the phenotype seen after loss of Sema6A function both at the ventral motor exit point and at the dorsal root entry site of the lumbosacral spinal cord. Loss of either PlexinA4 or Sema6D function had an effect only at the dorsal root entry site but not at the ventral motor axon exit point. Conclusion Sema6A acts as a gate keeper between the PNS and the CNS both ventrally and dorsally. It is required for the clustering of boundary cap cells at the PNS/CNS interface and, thus, prevents motoneurons from streaming out of the ventral spinal cord. At the dorsal root entry site it organizes the segregation of dorsal roots. PMID:18088409

Influence of microgravity on root-cap regeneration and the structure of columella cells in Zea mays

NASA Technical Reports Server (NTRS)

Moore, R.; McClelen, C. E.; Fondren, W. M.; Wang, C. L.

1987-01-01

We launched imbibed seeds and seedlings of Zea mays into outer space aboard the space shuttle Columbia to determine the influence of microgravity on 1) root-cap regeneration, and 2) the distribution of amyloplasts and endoplasmic reticulum (ER) in the putative statocytes (i.e., columella cells) of roots. Decapped roots grown on Earth completely regenerated their caps within 4.8 days after decapping, while those grown in microgravity did not regenerate caps. In Earth-grown seedlings, the ER was localized primarily along the periphery of columella cells, and amyloplasts sedimented in response to gravity to the lower sides of the cells. Seeds germinated on Earth and subsequently launched into outer space had a distribution of ER in columella cells similar to that of Earth-grown controls, but amyloplasts were distributed throughout the cells. Seeds germinated in outer space were characterized by the presence of spherical and ellipsoidal masses of ER and randomly distributed amyloplasts in their columella cells. These results indicate that 1) gravity is necessary for regeneration of the root cap, 2) columella cells can maintain their characteristic distribution of ER in microgravity only if they are exposed previously to gravity, and 3) gravity is necessary to distribute the ER in columella cells of this cultivar of Z. mays.

Lipogenesis and Redox Balance in Nitrogen-Fixing Pea Bacteroids.

PubMed

Terpolilli, Jason J; Masakapalli, Shyam K; Karunakaran, Ramakrishnan; Webb, Isabel U C; Green, Rob; Watmough, Nicholas J; Kruger, Nicholas J; Ratcliffe, R George; Poole, Philip S

2016-10-15

Within legume root nodules, rhizobia differentiate into bacteroids that oxidize host-derived dicarboxylic acids, which is assumed to occur via the tricarboxylic acid (TCA) cycle to generate NAD(P)H for reduction of N2 Metabolic flux analysis of laboratory-grown Rhizobium leguminosarum showed that the flux from [(13)C]succinate was consistent with respiration of an obligate aerobe growing on a TCA cycle intermediate as the sole carbon source. However, the instability of fragile pea bacteroids prevented their steady-state labeling under N2-fixing conditions. Therefore, comparative metabolomic profiling was used to compare free-living R. leguminosarum with pea bacteroids. While the TCA cycle was shown to be essential for maximal rates of N2 fixation, levels of pyruvate (5.5-fold reduced), acetyl coenzyme A (acetyl-CoA; 50-fold reduced), free coenzyme A (33-fold reduced), and citrate (4.5-fold reduced) were much lower in bacteroids. Instead of completely oxidizing acetyl-CoA, pea bacteroids channel it into both lipid and the lipid-like polymer poly-β-hydroxybutyrate (PHB), the latter via a type III PHB synthase that is active only in bacteroids. Lipogenesis may be a fundamental requirement of the redox poise of electron donation to N2 in all legume nodules. Direct reduction by NAD(P)H of the likely electron donors for nitrogenase, such as ferredoxin, is inconsistent with their redox potentials. Instead, bacteroids must balance the production of NAD(P)H from oxidation of acetyl-CoA in the TCA cycle with its storage in PHB and lipids. Biological nitrogen fixation by symbiotic bacteria (rhizobia) in legume root nodules is an energy-expensive process. Within legume root nodules, rhizobia differentiate into bacteroids that oxidize host-derived dicarboxylic acids, which is assumed to occur via the TCA cycle to generate NAD(P)H for reduction of N2 However, direct reduction of the likely electron donors for nitrogenase, such as ferredoxin, is inconsistent with their redox potentials. Instead, bacteroids must balance oxidation of plant-derived dicarboxylates in the TCA cycle with lipid synthesis. Pea bacteroids channel acetyl-CoA into both lipid and the lipid-like polymer poly-β-hydroxybutyrate, the latter via a type II PHB synthase. Lipogenesis is likely to be a fundamental requirement of the redox poise of electron donation to N2 in all legume nodules. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Lipogenesis and Redox Balance in Nitrogen-Fixing Pea Bacteroids

PubMed Central

Terpolilli, Jason J.; Masakapalli, Shyam K.; Karunakaran, Ramakrishnan; Webb, Isabel U. C.; Green, Rob; Watmough, Nicholas J.; Kruger, Nicholas J.; Ratcliffe, R. George

2016-01-01

ABSTRACT Within legume root nodules, rhizobia differentiate into bacteroids that oxidize host-derived dicarboxylic acids, which is assumed to occur via the tricarboxylic acid (TCA) cycle to generate NAD(P)H for reduction of N2. Metabolic flux analysis of laboratory-grown Rhizobium leguminosarum showed that the flux from [13C]succinate was consistent with respiration of an obligate aerobe growing on a TCA cycle intermediate as the sole carbon source. However, the instability of fragile pea bacteroids prevented their steady-state labeling under N2-fixing conditions. Therefore, comparative metabolomic profiling was used to compare free-living R. leguminosarum with pea bacteroids. While the TCA cycle was shown to be essential for maximal rates of N2 fixation, levels of pyruvate (5.5-fold reduced), acetyl coenzyme A (acetyl-CoA; 50-fold reduced), free coenzyme A (33-fold reduced), and citrate (4.5-fold reduced) were much lower in bacteroids. Instead of completely oxidizing acetyl-CoA, pea bacteroids channel it into both lipid and the lipid-like polymer poly-β-hydroxybutyrate (PHB), the latter via a type III PHB synthase that is active only in bacteroids. Lipogenesis may be a fundamental requirement of the redox poise of electron donation to N2 in all legume nodules. Direct reduction by NAD(P)H of the likely electron donors for nitrogenase, such as ferredoxin, is inconsistent with their redox potentials. Instead, bacteroids must balance the production of NAD(P)H from oxidation of acetyl-CoA in the TCA cycle with its storage in PHB and lipids. IMPORTANCE Biological nitrogen fixation by symbiotic bacteria (rhizobia) in legume root nodules is an energy-expensive process. Within legume root nodules, rhizobia differentiate into bacteroids that oxidize host-derived dicarboxylic acids, which is assumed to occur via the TCA cycle to generate NAD(P)H for reduction of N2. However, direct reduction of the likely electron donors for nitrogenase, such as ferredoxin, is inconsistent with their redox potentials. Instead, bacteroids must balance oxidation of plant-derived dicarboxylates in the TCA cycle with lipid synthesis. Pea bacteroids channel acetyl-CoA into both lipid and the lipid-like polymer poly-β-hydroxybutyrate, the latter via a type II PHB synthase. Lipogenesis is likely to be a fundamental requirement of the redox poise of electron donation to N2 in all legume nodules. PMID:27501983

Ion Relations of Symplastic and Apoplastic Space in Leaves from Spinacia oleracea L. and Pisum sativum L. under Salinity 1

PubMed Central

Speer, Michael; Kaiser, Werner M.

1991-01-01

Salt tolerant spinach (Spinacia oleracea) and salt sensitive pea (Pisum sativum) plants were exposed to mild salinity under identical growth conditions. In order to compare the ability of the two species for extra- and intracellular solute compartmentation in leaves, various solutes were determined in intercellular washing fluids and in aqueously isolated intact chloroplasts. In pea plants exposed to 100 millimolar NaCl for 14 days, apoplastic salt concentrations in leaflets increased continuously with time up to 204 (Cl−) and 87 millimolar (Na+), whereas the two ions reached a steady concentration of only 13 and 7 millimolar, respectively, in spinach leaves. In isolated intact chloroplasts from both species, sodium concentrations were not much different, but chloride concentrations were significantly higher in pea than in spinach. Together with data from whole leaf extracts, these measurements permitted an estimation of apoplastic, cytoplasmic, and vacuolar solute concentrations. Sodium and chloride concentration gradients across the tonoplast were rather similar in both species, but spinach was able to maintain much steeper sodium gradients across the plasmamembrane compared with peas. Between day 12 and day 17, concentrations of other inorganic ions in the pea leaf apoplast increased abruptly, indicating the onset of cell disintegration. It is concluded that the differential salt sensitivity of pea and spinach cannot be traced back to a single plant performance. Major differences appear to be the inability of pea to control salt accumulation in the shoot, to maintain steep ion gradients across the leaf cell plasmalemma, and to synthesize compatible solutes. Perhaps less important is a lower selectivity of pea for K+/Na+ and NO3−/Cl− uptake by roots. PMID:16668541

[Content of salicylic and jasmonic acids in pea roots (Pisum sativum L.) at the initial stage of symbiotic or pathogenic interaction with bacteria of the family Rhizobiaceae].

PubMed

Rudikovskaya, E G; Akimova, G P; Rudikovskii, A V; Katysheva, N B; Dudareva, L V

2017-01-01

A change in the contents of endogenous salicylic and jasmonic acids in the roots of the host plant at the preinfectious stage of interaction with symbiotic (Rhizobium leguminosarum) and pathogenic (Agrobacterium rizogenes) bacteria belonging for to the family Rhizobiaceae was studied. It was found that the jasmonic acid content increased 1.5–2 times 5 min after inoculation with these bacterial species. It was shown that dynamics of the change in the JA and SA contents depends on the type of infection. Thus, the JA content decreased in the case of pathogenesis, while the SA content increased. At the same time, an increased JA content was observed during symbiosis. The observed regularities could indicate the presence of different strategies of hormonal regulation for interaction with symbiotic and pathogenic bacteria belonging to the family Rhizobiaceae in peas plants.

Escaping Underground Nets: Extracellular DNases Degrade Plant Extracellular Traps and Contribute to Virulence of the Plant Pathogenic Bacterium Ralstonia solanacearum

PubMed Central

Tran, Tuan Minh; MacIntyre, April; Hawes, Martha; Allen, Caitilyn

2016-01-01

Plant root border cells have been recently recognized as an important physical defense against soil-borne pathogens. Root border cells produce an extracellular matrix of protein, polysaccharide and DNA that functions like animal neutrophil extracellular traps to immobilize pathogens. Exposing pea root border cells to the root-infecting bacterial wilt pathogen Ralstonia solanacearum triggered release of DNA-containing extracellular traps in a flagellin-dependent manner. These traps rapidly immobilized the pathogen and killed some cells, but most of the entangled bacteria eventually escaped. The R. solanacearum genome encodes two putative extracellular DNases (exDNases) that are expressed during pathogenesis, suggesting that these exDNases contribute to bacterial virulence by enabling the bacterium to degrade and escape root border cell traps. We tested this hypothesis with R. solanacearum deletion mutants lacking one or both of these nucleases, named NucA and NucB. Functional studies with purified proteins revealed that NucA and NucB are non-specific endonucleases and that NucA is membrane-associated and cation-dependent. Single ΔnucA and ΔnucB mutants and the ΔnucA/B double mutant all had reduced virulence on wilt-susceptible tomato plants in a naturalistic soil-soak inoculation assay. The ΔnucA/B mutant was out-competed by the wild-type strain in planta and was less able to stunt root growth or colonize plant stems. Further, the double nuclease mutant could not escape from root border cells in vitro and was defective in attachment to pea roots. Taken together, these results demonstrate that extracellular DNases are novel virulence factors that help R. solanacearum successfully overcome plant defenses to infect plant roots and cause bacterial wilt disease. PMID:27336156

Cytochemical localization of calcium in cap cells of primary roots of Zea mays L

NASA Technical Reports Server (NTRS)

Moore, R.

1986-01-01

The distribution of calcium (Ca) in caps of vertically- and horizontally-oriented roots of Zea mays was monitored to determine its possible role in root graviresponsiveness. A modification of the antimonate precipitation procedure was used to localize Ca in situ. In vertically-oriented roots, the presumed graviperceptive (i.e., columella) cells were characterized by minimal and symmetric staining of the plasmalemma and mitochondria. No precipitate was present in plasmodesmata or cell walls. Within 5 min after horizontal reorientation, staining was associated with the portion of the cell wall adjacent to the distal end of the cell. This asymmetric staining persisted throughout the onset of gravicurvature. No staining of lateral cell walls of columella cells was observed at any stage of gravicurvature, suggesting that a lateral flow of Ca through the columella tissue of horizontally-oriented roots does not occur. The outermost peripheral cells of roots oriented horizontally and vertically secrete Ca through plasmodesmata-like structures in their cell walls. These results are discussed relative to proposed roles of root-cap Ca in root gravicurvature.

Mutation of praR in Rhizobium leguminosarum enhances root biofilms, improving nodulation competitiveness by increased expression of attachment proteins

PubMed Central

Frederix, Marijke; Edwards, Anne; Swiderska, Anna; Stanger, Andrew; Karunakaran, Ramakrishnan; Williams, Alan; Abbruscato, Pamela; Sanchez-Contreras, Maria; Poole, Philip S; Downie, J Allan

2014-01-01

In Rhizobium leguminosarum bv. viciae, quorum-sensing is regulated by CinR, which induces the cinIS operon. CinI synthesizes an AHL, whereas CinS inactivates PraR, a repressor. Mutation of praR enhanced biofilms in vitro. We developed a light (lux)-dependent assay of rhizobial attachment to roots and demonstrated that mutation of praR increased biofilms on pea roots. The praR mutant out-competed wild-type for infection of pea nodules in mixed inoculations. Analysis of gene expression by microarrays and promoter fusions revealed that PraR represses its own transcription and mutation of praR increased expression of several genes including those encoding secreted proteins (the adhesins RapA2, RapB and RapC, two cadherins and the glycanase PlyB), the polysaccharide regulator RosR, and another protein similar to PraR. PraR bound to the promoters of several of these genes indicating direct repression. Mutations in rapA2, rapB, rapC, plyB, the cadherins or rosR did not affect the enhanced root attachment or nodule competitiveness of the praR mutant. However combinations of mutations in rapA, rapB and rapC abolished the enhanced attachment and nodule competitiveness. We conclude that relief of PraR-mediated repression determines a lifestyle switch allowing the expression of genes that are important for biofilm formation on roots and the subsequent initiation of infection of legume roots. PMID:24942546

Properties of Plasma Membrane from Pea Root Seedlings under Altered Gravity

NASA Astrophysics Data System (ADS)

Klymchuk, D.; Baranenko, V.; Vorobyova, T. V.; Kurylenko, I.; Chyzhykova, O.; Dubovoy, V.

In this study, the properties of pea (Pisum sativum L.) plasma membrane were examined to determine how the membrane structure and functions are regulated in response to clinorotation (2 rev/min) conditions. Membrane preparations enriched by plasma membrane vesicles were obtained by aqueous two-phase partitioning from 6-day seedling roots. The specific characteristics of H^+-ATPase, lípid composition and peroxidation intensity as well as fluidity of lipid bilayer were analysed. ATP hydrolytic activity was inhibited by ortovanadate and was insensitive to aside and nitrate in sealed plasma membrane vesicles isolated from both clinorotated and control seedlings. Plasma membrane vesicles from clinorotated seedlings in comparison to controls were characterised by increase in the total lipid/protein ratio, ATP hydrolytic activity and intensifying of lipid peroxidation. Sitosterol and campesterol were the predominant free sterol species. Clinorotated seedlings contained a slightly higher level of unsaturated fatty acid than controls. Plasma membrane vesicles were labelled with pyrene and fluorescence originating from monomeric (I_M) molecules and excimeric (I_E) aggregates were measured. The calculated I_E/I_M values were higher in clinorotated seedlings compared with controls reflecting the reduction in membrane microviscosity. The involvement of the changes in plasma membrane lipid content and composition, fluidity and H^+-ATPase activity in response of pea seedlings to altered gravity is discussed.

An active role of the amyloplasts and nuclei of root statocytes in graviperception

NASA Technical Reports Server (NTRS)

Kordyum, E.; Guikema, J.

2001-01-01

Three main phases are discerned in the gravitropic reaction: perception of a gravitational stimulus, its transduction, and fixation of the reaction resulting in bending of an organ. According to the starch-statolith hypothesis of Nemec and Haberlandt, amyloplasts in the structurally and functionally specialized graviperceptive cells (statocytes) sediment in the direction of a gravitational vector in the distal part of a cell while a nucleus is in the proximal one. If amyloplasts appear to act as gravity sensors, the receptors, which interact with sedimented amyloplasts, and next signaling are still unclear. An analysis of the structural-functional organization of cells in different root cap layers of such higher plants as pea, Arabidopsis thaliana, and Brassica rapa grown under 1 g, on the clinostats, and in microgravity, allows us to support the hypothesis that amyloplasts function as statoliths in statocytes, but they may not be only the passive statolithic mass. We propose that amyloplasts fulfill a more complex function by interacting with a receptor, which is a nucleus, in transduction of some signal to it. Gravity-induced statolith movement in certain order leads to a new functional connection between gravity susceptors--amyloplasts and a receptor--a nucleus receiving some signal presumedly of a mechanical or biochemical nature from the amyloplasts. During gravitropism, sugar signaling could induce expression of genes encoding auxin transport proteins in a nucleus giving the nucleus an intermediate role in signal trunsduction following perception. c 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

An active role of the amyloplasts and nuclei of root statocytes in graviperception

NASA Astrophysics Data System (ADS)

Kordyum, E.; Guikema, J.

Three main phases are discerned in the gravitropic reaction: perception of a gravitational stimulus, its transduction, and fixation of the reaction resulting in bending of an organ. According to the starch-statolith hypothesis of Nemec and Haberlandt, amyloplasts in the structurally and functionally specialized graviperceptive cells (statocytes) sediment in the direction of a gravitational vector in the distal part of a cell while a nucleus is in the proximal one. If amyloplasts appear to act as gravity sensors, the receptors, which interact with sedimented amyloplasts, and next signaling are still unclear. An analysis of the structural-functional organization of cells in different root cap layers of such higher plants as pea, Arabidopsis thaliana, and Brassica rapa grown under 1 g, on the clinostats, and in microgravity, allows us to support the hypothesis that amyloplasts function as statoliths in statocytes, but they may not be only the passive statolithic mass. We propose that amyloplasts fulfill a more complex function by interacting with a receptor, which is a necleus, in transduction of some signal to it. Gravity-induced statolith movement in certain order leads to a new functional connection between gravity susceptors - amyloplasts and a receptor - a nucleus receiving some signal presumedly of a mechanical or biochemical nature from the amyloplasts. During gravitropism, sugar signaling could induce expression of genes encoding auxin transport proteins in a nucleus giving the nucleus an intermediate role in signal trunsduction following perception.

Ultrastructure of the root cap of Arabidopsis Thaliana L. Heynh under spaceflight conditions

NASA Technical Reports Server (NTRS)

1983-01-01

Peculiarities of the ultrastructural organization of Arabidopsis root cap cells grown from the stage of two cotyledonous leaves in the Svetoblok-1 apparatus aboard the Salyut 6 research orbital station and in the laboratory are assessed. It is established that under conditions of real space flight vacuolization of the root cap cells increses considerably compared to the control variant. Changes in the topography and ulstrastructure of amyloplasts as well as lysis of cell walls are observed in the material under study. An assumption is advanced on analogous cell responses observed at the ultrastructural level to weightlessness and clinostatic conditions.

The role of strigolactones in photomorphogenesis of pea is limited to adventitious rooting.

PubMed

Urquhart, Shelley; Foo, Eloise; Reid, James B

2015-03-01

The recently discovered group of plant hormones, the strigolactones, have been implicated in regulating photomorphogenesis. We examined this extensively in our strigolactone synthesis and response mutants and could find no evidence to support a major role for strigolactone signaling in classic seedling photomorphogenesis (e.g. elongation and leaf expansion) in pea (Pisum sativum), consistent with two recent independent reports in Arabidopsis. However, we did find a novel effect of strigolactones on adventitious rooting in darkness. Strigolactone-deficient mutants, Psccd8 and Psccd7, produced significantly fewer adventitious roots than comparable wild-type seedlings when grown in the dark, but not when grown in the light. This observation in dark-grown plants did not appear to be due to indirect effects of other factors (e.g. humidity) as the constitutively de-etiolated mutant, lip1, also displayed reduced rooting in the dark. This role for strigolactones did not involve the MAX2 F-Box strigolactone response pathway as Psmax2 f-box mutants did not show a reduction in adventitious rooting in the dark compared with wild-type plants. The auxin-deficient mutant bushy also reduced adventitious rooting in the dark, as did decapitation of wild-type plants. Rooting was restored by the application of indole-3-acetic acid (IAA) to decapitated plants, suggesting a role for auxin in the rooting response. However, auxin measurements showed no accumulation of IAA in the epicotyls of wild-type plants compared with the strigolactone synthesis mutant Psccd8, suggesting that changes in the gross auxin level in the epicotyl are not mediating this response to strigolactone deficiency. © 2014 Scandinavian Plant Physiology Society.

Outcomes of direct pulp capping: interrogating an insurance database.

PubMed

Raedel, M; Hartmann, A; Bohm, S; Konstantinidis, I; Priess, H W; Walter, M H

2016-11-01

To evaluate the effectiveness of direct pulp capping under general practice conditions. It was hypothesized that direct pulp capping is an effective procedure in the majority of cases and prevents the need for root canal treatment or extraction. Claims data were collected from the digital database of a major German national health insurance company. Only patients who had been insurance members for the entire 3 year period 2010 to 2012 were eligible. Kaplan-Meier survival analyses were conducted for all teeth with direct pulp capping. Success was defined as not undergoing root canal treatment. Survival was defined as not undergoing extraction. Differences between survival functions were tested with the log rank test. A total of 148 312 teeth were included. The overall success rate was 71.6% at 3 years. The overall survival rate was 95.9% at 3 years. The success rates for single-rooted teeth (71.8%) and multirooted teeth (71.5%) were similar although significantly different (P < 0.001). Best 3-year success rates were found at low (79.7%; <18 years.) and very high age (81.8%; >85 years.). After direct pulp capping, more than two-thirds of the affected teeth did not undergo root canal treatment within 3 years. Although this study has the typical limits of a claims data analysis, it can be concluded that direct pulp capping is an effective intervention to avoid root canal treatment and extraction in a general practice setting. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Abscisic Acid Stimulates Elongation of Excised Pea Root Tips

PubMed Central

Gaither, Douglas H.; Lutz, Donald H.; Forrence, Leonard E.

1975-01-01

Excised Pisum sativum L. root tips were incubated in a pH 5.2 sucrose medium containing abscisic acid. Elongation growth was inhibited by 100 μm abscisic acid. However, decreasing the abscisic acid concentration caused stimulation of elongation, the maximum response (25% to 30%) occurring at 1 μm abscisic acid. Prior to two hours, stimulation of elongation by 1 μm abscisic acid was not detectable. Increased elongation did not occur in abscisic acid-treated root tips of Lens culinaris L., Phaseolus vulgaris L., or Zea mays L. PMID:16659198

40 CFR 180.626 - Prothioconazole; tolerances for residues.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Alfalfa, forage 0.02 Alfalfa, hay 0.02 Beet, sugar, roots 0.25 Corn, sweet kernel plus cob with husks... sweet corn and sorghum 0.35 Pea and bean, dried shelled, except soybean, subgroup 6C 0.9 Peanut 0.02...

40 CFR 180.626 - Prothioconazole; tolerances for residues.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Alfalfa, forage 0.02 Alfalfa, hay 0.02 Beet, sugar, roots 0.25 Corn, sweet kernel plus cob with husks... sweet corn and sorghum 0.35 Pea and bean, dried shelled, except soybean, subgroup 6C 0.9 Peanut 0.02...

Long-term iron deficiency: Tracing changes in the proteome of different pea (Pisum sativum L.) cultivars.

PubMed

Meisrimler, Claudia-Nicole; Wienkoop, Stefanie; Lyon, David; Geilfus, Christoph-Martin; Lüthje, Sabine

2016-05-17

Iron deficiency (-Fe) is one of the major problems in crop production. Dicots, like pea (Pisum sativum L.), are Strategy I plants, which induce a group of specific enzymes such as Fe(III)-chelate reductase (FRO), Fe responsive transporter (IRT) and H(+)-ATPase (HA) at the root plasma membrane under -Fe. Different species and cultivars have been shown to react diversely to -Fe. Furthermore, different kinds of experimental set-ups for -Fe have to be distinguished: i) short-term vs. long-term, ii) constant vs. acute alteration and iii) buffered vs. unbuffered systems. The presented work compares the effects of constant long-term -Fe in an unbuffered system on roots of four different pea cultivars in a timely manner (12, 19 and 25days). To differentiate the effects of -Fe and plant development, control plants (+Fe) were analyzed in comparison to -Fe plants. Besides physiological measurements, an integrative study was conducted using a comprehensive proteome analysis. Proteins, related to stress adaptation (e.g. HSP), reactive oxygen species related proteins and proteins of the mitochondrial electron transport were identified to be changed in their abundance. Regulations and possible functions of identified proteins are discussed. Pea (Pisum sativum L.) belongs to the legume family (Fabaceae) and is an important crop plant due to high Fe, starch and protein contents. According to FAOSTAT data (September 2015), world production of the garden pea quadrupled from 1970 to 2012. Since the initial studies by Gregor Mendel, the garden pea became the most-characterized legume and has been used in numerous investigations in plant biochemistry and physiology, but is not well represented in the "omics"-related fields. A major limitation in pea production is the Fe availability from soils. Adaption mechanisms to Fe deficiency vary between species, and even cultivars have been shown to react diversely. A label-free proteomic approach, in combination with physiological measurements, was chosen to observe four different pea cultivars for 5 to 25days. Physiological and proteome data showed that cultivar Blauwschokker and Vroege were more susceptible to -Fe than cultivar Kelvedon (highly efficient) and GftR (semi-efficient). Proteomic data hint that the adaptation process to long-term -Fe takes place between days 19 and 25. Results show that adaptation processes of efficient cultivars are able to postpone secondary negative effects of long-term -Fe, possibly by stabilizing the protein metabolic processing and the mitochondrial electron transport components. This maintains the cellular energy proliferation, keeps ROS production low and postpones the mitochondrial cell death signal. Copyright © 2016 Elsevier B.V. All rights reserved.

Actin Turnover-Mediated Gravity Response in Maize Root Apices

PubMed Central

Mancuso, Stefano; Barlow, Peter W; Volkmann, Dieter

2006-01-01

The dynamic actin cytoskeleton has been proposed to be linked to gravity sensing in plants but the mechanistic understanding of these processes remains unknown. We have performed detailed pharmacological analyses of the role of the dynamic actin cytoskeleton in gravibending of maize (Zea mays) root apices. Depolymerization of actin filaments with two drugs having different mode of their actions, cytochalasin D and latrunculin B, stimulated root gravibending. By contrast, drug-induced stimulation of actin polymerization and inhibition of actin turnover, using two different agents phalloidin and jasplakinolide, compromised the root gravibending. Importantly, all these actin drugs inhibited root growth to similar extents suggesting that high actin turnover is essential for the gravity-related growth responses rather than for the general growth process. Both latrunculin B and cytochalasin D treatments inhibited root growth but restored gravibending of the decapped root apices, indicating that there is a strong potential for effective actin-mediated gravity sensing outside the cap. This elusive gravity sensing outside the root cap is dependent not only on the high rate of actin turnover but also on weakening of myosin activities, as general inhibition of myosin ATPases induced stimulation of gravibending of the decapped root apices. Collectively, these data provide evidence for the actin turnover-mediated gravity sensing outside the root cap. PMID:19521476

Cytogenetic evaluation of gold nanorods using Allium cepa test.

PubMed

Rajeshwari, A; Roy, Barsha; Chandrasekaran, Natarajan; Mukherjee, Amitava

2016-12-01

The current study reveals the impact of gold nanorods (NRs) capped with CTAB (cetyltrimethylammonium bromide) or PEG (polyethylene glycol) on Allium cepa. The morphology and surface charge of CTAB- and PEG-capped gold NRs were characterized by electron microscopic and zeta potential analyses. The chromosomal aberrations like clumped chromosome, chromosomal break, chromosomal bridge, diagonal anaphase, disturbed metaphase, laggard chromosome, and sticky chromosome were observed in the root tip cells exposed to different concentrations (0.1, 1, and 10 μg/mL) of CTAB- and PEG-capped gold NRs. We found that both CTAB- and PEG-capped gold NRs were able to induce toxicity in the plant system after 4-h interaction. At a maximum concentration of 10 μg/mL, the mitotic index reduction induced by CTAB-capped gold NRs was 40-fold higher than that induced by PEG-capped gold NRs. The toxicity of gold NRs was further confirmed by lipid peroxidation and oxidative stress analyses. The unbound CTAB also contributed to the toxicity in root tip cells, while PEG alone shows less toxicity to the cells. The vehicle control CTAB contributed to the toxic effects in root tip cells, while PEG alone did not show any toxicity to the cells. The results revealed that even though both the particles have adverse effects on A. cepa, there was a significant difference in the mitotic index and oxidative stress generation in root cells exposed to CTAB-capped gold NRs. Thus, this study concludes that the surface polymerization of gold NRs by PEG can reduce the toxicity of CTAB-capped gold NRs. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

New class of radioenzymatic assay for the quantification of p-tyramine and phenylethylamine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Henry, D.P.; Van Huysse, J.W.; Bowsher, R.R.

Radioenzymatic assays are widely used for the quantification of a number of biogenic amines. All previous procedures have utilized methyltransferases derived from mammalian tissues. In this assay for the quantification of the trace aralkylamines, p-tyramine (p-tym) and phenylethylamine (PEA), an enzyme, tyramine N-methyltransferase isolated from sprouted barley roots was used. The enzyme was specific for phenylethylamines. Of 26 structurally-related compounds, only p-tym, PEA, m-tym and amphetamine were substrates in vitro. Theoretic maximal methylation of substrates occurred at 10-20/sup 0/C. When TLC was used to separate the radiolabeled reaction products, a specific method was developed for p-tym and PEA. The assaymore » had a sensitivity of 0.8 and 2.8 pg/tube with a C.V. < 5% and was applicable to human plasma and urine. Assay throughput is similar to that of other TLC based radioenzymatic assays.« less

A chemically induced new pea (Pisum sativum) mutant SGECdt with increased tolerance to, and accumulation of, cadmium.

PubMed

Tsyganov, Viktor E; Belimov, Andrei A; Borisov, Alexey Y; Safronova, Vera I; Georgi, Manfred; Dietz, Karl-Josef; Tikhonovich, Igor A

2007-02-01

To date, there are no crop mutants described in the literature that display both Cd accumulation and tolerance. In the present study a unique pea (Pisum sativum) mutant SGECd(t) with increased Cd tolerance and accumulation was isolated and characterized. Ethylmethane sulfonate mutagenesis of the pea line SGE was used to obtain the mutant. Screening for Cd-tolerant seedlings in the M2 generation was performed using hydroponics in the presence of 6 microm CdCl2. Hybridological analysis was used to identify the inheritance of the mutant phenotype. Several physiological and biochemical characteristics of SGECd(t) were studied in hydroponic experiments in the presence of 3 microm CdCl2, and elemental analysis was conducted. The mutant SGECd(t) was characterized as having a monogenic inheritance and a recessive phenotype. It showed increased Cd concentrations in roots and shoots but no obvious morphological defects, demonstrating its capability to cope well with increased Cd levels in its tissues. The enhanced Cd accumulation in the mutant was accompanied by maintenance of homeostasis of shoot Ca, Mg, Zn and Mn contents, and root Ca and Mg contents. Through the application of La(+3) and the exclusion of Ca from the nutrient solution, maintenance of nutrient homeostasis in Cd-stressed SGECd(t) was shown to contribute to the increased Cd tolerance. Control plants of the mutant (i.e. no Cd treatment) had elevated concentrations of glutathione (GSH) in the roots. Through measurements of chitinase and guaiacol-dependent peroxidase activities, as well as proline and non-protein thiol (NPT) levels, it was shown that there were lower levels of Cd stress both in roots and shoots of SGECd(t). Accumulation of phytochelatins [(PCcalculated) = (NPT)-(GSH)] could be excluded as a cause of the increased Cd tolerance in the mutant. The SGECd(t) mutant represents a novel and unique model to study adaptation of plants to toxic heavy metal concentrations.

Organization of cortical microtubules in graviresponding maize roots

NASA Technical Reports Server (NTRS)

Blancaflor, E. B.; Hasenstein, K. H.

1993-01-01

Immunofluorescence labeling of cortical microtubules (MTs) was used to investigate the relationship between MT arrangement and changes in growth rate of the upper and lower sides of horizontally placed roots of maize (Zea mays L. cv. Merit). Cap cells and cells of the elongation zone of roots grown vertically in light or darkness showed MT arrangements that were transverse (perpendicular) to the growth direction. Microtubules of cells basal to the elongation zone typically showed oblique orientation. Two hours after horizontal reorientation, cap cells of gravicompetent, light-grown and curving roots contained MTs parallel to the gravity vector. The MT arrangement on the upper side of the elongation zone remained transverse but the MTs of the outer four to five layers of cortical cells along the lower side of the elongation zone showed reorientation parallel to the axis of the root. The MTs of the lower epidermis retained their transverse orientation. Dark-grown roots did not curve and did not show reorientation of MTs in cells of the root cap or elongation zone. The data indicate that MT depolymerization and reorientation is correlated with reduction in growth rate, and that MT reorientation is one of the steps of growth control of graviresponding roots.

Wind blade spar cap and method of making

DOEpatents

Mohamed, Mansour H [Raleigh, NC

2008-05-27

A wind blade spar cap for strengthening a wind blade including an integral, unitary three-dimensional woven material having a first end and a second end, corresponding to a root end of the blade and a tip end of the blade, wherein the material tapers in width from the first to the second end while maintaining a constant thickness and decreasing weight therebetween, the cap being capable of being affixed to the blade for providing increased strength with controlled variation in weight from the root end to the tip end based upon the tapered width of the material thereof. The present inventions also include the method of making the wind blade spar cap and a wind blade including the wind blade spar cap.

Root gravitropism: a complex response to a simple stimulus?

NASA Technical Reports Server (NTRS)

Rosen, E.; Chen, R.; Masson, P. H.

1999-01-01

Roots avoid depleting their immediate environment of essential nutrients by continuous growth. Root growth is directed by environmental cues, including gravity. Gravity sensing occurs mainly in the columella cells of the root cap. Upon reorientation within the gravity field, the root-cap amyloplasts sediment, generating a physiological signal that promotes the development of a curvature at the root elongation zones. Recent molecular genetic studies in Arabidopsis have allowed the identification of genes that play important roles in root gravitropism. Among them, the ARG1 gene encodes a DnaJ-like protein involved in gravity signal transduction, whereas the AUX1 and AGR1 genes encode proteins involved in polar auxin transport. These studies have important implications for understanding the intra- and inter-cellular signaling processes that underlie root gravitropism.

Mutation of praR in Rhizobium leguminosarum enhances root biofilms, improving nodulation competitiveness by increased expression of attachment proteins.

PubMed

Frederix, Marijke; Edwards, Anne; Swiderska, Anna; Stanger, Andrew; Karunakaran, Ramakrishnan; Williams, Alan; Abbruscato, Pamela; Sanchez-Contreras, Maria; Poole, Philip S; Downie, J Allan

2014-08-01

In Rhizobium leguminosarum bv. viciae, quorum-sensing is regulated by CinR, which induces the cinIS operon. CinI synthesizes an AHL, whereas CinS inactivates PraR, a repressor. Mutation of praR enhanced biofilms in vitro. We developed a light (lux)-dependent assay of rhizobial attachment to roots and demonstrated that mutation of praR increased biofilms on pea roots. The praR mutant out-competed wild-type for infection of pea nodules in mixed inoculations. Analysis of gene expression by microarrays and promoter fusions revealed that PraR represses its own transcription and mutation of praR increased expression of several genes including those encoding secreted proteins (the adhesins RapA2, RapB and RapC, two cadherins and the glycanase PlyB), the polysaccharide regulator RosR, and another protein similar to PraR. PraR bound to the promoters of several of these genes indicating direct repression. Mutations in rapA2, rapB, rapC, plyB, the cadherins or rosR did not affect the enhanced root attachment or nodule competitiveness of the praR mutant. However combinations of mutations in rapA, rapB and rapC abolished the enhanced attachment and nodule competitiveness. We conclude that relief of PraR-mediated repression determines a lifestyle switch allowing the expression of genes that are important for biofilm formation on roots and the subsequent initiation of infection of legume roots. © 2014 The Authors. Molecular Microbiology published by John Wiley & Sons Ltd.

Cell wall-bound cationic and anionic class III isoperoxidases of pea root: biochemical characterization and function in root growth.

PubMed

Kukavica, Biljana M; Veljovicc-Jovanovicc, Sonja D; Menckhoff, Ljiljana; Lüthje, Sabine

2012-07-01

Cell wall isolated from pea roots was used to separate and characterize two fractions possessing class III peroxidase activity: (i) ionically bound proteins and (ii) covalently bound proteins. Modified SDS-PAGE separated peroxidase isoforms by their apparent molecular weights: four bands of 56, 46, 44, and 41kDa were found in the ionically bound fraction (iPOD) and one band (70kDa) was resolved after treatment of the cell wall with cellulase and pectinase (cPOD). Isoelectric focusing (IEF) patterns for iPODs and cPODs were significantly different: five iPODs with highly cationic pI (9.5-9.2) were detected, whereas the nine cPODs were anionic with pI values between pH 3.7 and 5. iPODs and cPODs showed rather specific substrate affinity and different sensitivity to inhibitors, heat, and deglycosylation treatments. Peroxidase and oxidase activities and their IEF patterns for both fractions were determined in different zones along the root and in roots of different ages. New iPODs with pI 9.34 and 9.5 were induced with root growth, while the activity of cPODs was more related to the formation of the cell wall in non-elongating tissue. Treatment with auxin that inhibits root growth led to suppression of iPOD and induction of cPOD. A similar effect was obtained with the widely used elicitor, chitosan, which also induced cPODs with pI 5.3 and 5.7, which may be specifically related to pathogen defence. The differences reported here between biochemical properties of cPOD and iPOD and their differential induction during development and under specific treatments implicate that they are involved in specific and different physiological processes.

Genome-wide association mapping of partial resistance to Aphanomyces euteiches in pea.

PubMed

Desgroux, Aurore; L'Anthoëne, Virginie; Roux-Duparque, Martine; Rivière, Jean-Philippe; Aubert, Grégoire; Tayeh, Nadim; Moussart, Anne; Mangin, Pierre; Vetel, Pierrick; Piriou, Christophe; McGee, Rebecca J; Coyne, Clarice J; Burstin, Judith; Baranger, Alain; Manzanares-Dauleux, Maria; Bourion, Virginie; Pilet-Nayel, Marie-Laure

2016-02-20

Genome-wide association (GWA) mapping has recently emerged as a valuable approach for refining the genetic basis of polygenic resistance to plant diseases, which are increasingly used in integrated strategies for durable crop protection. Aphanomyces euteiches is a soil-borne pathogen of pea and other legumes worldwide, which causes yield-damaging root rot. Linkage mapping studies reported quantitative trait loci (QTL) controlling resistance to A. euteiches in pea. However the confidence intervals (CIs) of these QTL remained large and were often linked to undesirable alleles, which limited their application in breeding. The aim of this study was to use a GWA approach to validate and refine CIs of the previously reported Aphanomyces resistance QTL, as well as identify new resistance loci. A pea-Aphanomyces collection of 175 pea lines, enriched in germplasm derived from previously studied resistant sources, was evaluated for resistance to A. euteiches in field infested nurseries in nine environments and with two strains in climatic chambers. The collection was genotyped using 13,204 SNPs from the recently developed GenoPea Infinium® BeadChip. GWA analysis detected a total of 52 QTL of small size-intervals associated with resistance to A. euteiches, using the recently developed Multi-Locus Mixed Model. The analysis validated six of the seven previously reported main Aphanomyces resistance QTL and detected novel resistance loci. It also provided marker haplotypes at 14 consistent QTL regions associated with increased resistance and highlighted accumulation of favourable haplotypes in the most resistant lines. Previous linkages between resistance alleles and undesired late-flowering alleles for dry pea breeding were mostly confirmed, but the linkage between loci controlling resistance and coloured flowers was broken due to the high resolution of the analysis. A high proportion of the putative candidate genes underlying resistance loci encoded stress-related proteins and others suggested that the QTL are involved in diverse functions. This study provides valuable markers, marker haplotypes and germplasm lines to increase levels of partial resistance to A. euteiches in pea breeding.

A new genetic factor for root gravitropism in rice (Oryza sativa L.).

PubMed

Shi, Jiang-hua; Hao, Xi; Wu, Zhong-chang; Wu, Ping

2009-10-01

Root gravitropism is one of the important factors to determine root architecture. To understand the mechanism underlying root gravitropism, we isolated a rice (Xiushui63) mutant defective in root gravitropism, designated as gls1. Vertical sections of root caps revealed that gls1 mutant displayed normal distribution of amyloplast in the columella cells compared with the wild type. The gls1 mutant was less sensitive to 2,4-dichlorophenoxyacetic acid (2,4-D) and alpha-naphthaleneacetic acid (NAA) than the wild type. Genetic analysis indicated that the phenotype of gls1 mutant was caused by a single recessive mutation, which is mapped in a 255-kb region between RM16253 and CAPS1 on the short arm of chromosome 4.

Adaptation of Rhizobium leguminosarum to pea, alfalfa and sugar beet rhizospheres investigated by comparative transcriptomics

PubMed Central

2011-01-01

Background The rhizosphere is the microbe-rich zone around plant roots and is a key determinant of the biosphere's productivity. Comparative transcriptomics was used to investigate general and plant-specific adaptations during rhizosphere colonization. Rhizobium leguminosarum biovar viciae was grown in the rhizospheres of pea (its legume nodulation host), alfalfa (a non-host legume) and sugar beet (non-legume). Gene expression data were compared to metabolic and transportome maps to understand adaptation to the rhizosphere. Results Carbon metabolism was dominated by organic acids, with a strong bias towards aromatic amino acids, C1 and C2 compounds. This was confirmed by induction of the glyoxylate cycle required for C2 metabolism and gluconeogenesis in all rhizospheres. Gluconeogenesis is repressed in R. leguminosarum by sugars, suggesting that although numerous sugar and putative complex carbohydrate transport systems are induced in the rhizosphere, they are less important carbon sources than organic acids. A common core of rhizosphere-induced genes was identified, of which 66% are of unknown function. Many genes were induced in the rhizosphere of the legumes, but not sugar beet, and several were plant specific. The plasmid pRL8 can be considered pea rhizosphere specific, enabling adaptation of R. leguminosarum to its host. Mutation of many of the up-regulated genes reduced competitiveness for pea rhizosphere colonization, while two genes specifically up-regulated in the pea rhizosphere reduced colonization of the pea but not alfalfa rhizosphere. Conclusions Comparative transcriptome analysis has enabled differentiation between factors conserved across plants for rhizosphere colonization as well as identification of exquisite specific adaptation to host plants. PMID:22018401

Immunological characterization of plant ornithine transcarbamylases

NASA Technical Reports Server (NTRS)

Slocum, R. D.; Williamson, C. L.; Poggenburg, C. A.; Lynes, M. A.

1990-01-01

Pea (Pisum sativum L.) ornithine transcarbamylase (OTC) antisera were used to investigate the immunological relatedness of several plant and animal OTC enzymes. The antisera immunoprecipitated OTC activity in all monocot and dicot species tested, and sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis of immunoprecipitated protein revealed monomeric proteins ranging from 35,200 to 36,800 daltons in size. Pea OTC antisera did not recognize mammalian OTC protein. OTC activity and protein levels detected on sodium dodecyl sulfate polyacrylamide gel electrophoresis immunoblots from homogenates of green leaf, etiolated epicotyl and cotyledon, and root tissues of pea were poorly correlated. This might result from differences in amounts of enzymatically active OTC protein in the homogenates. Alternatively, the antisera may fail to recognize different isozyme forms of OTC, which have been reported for some plant species. A putative cytosolic precursor OTC (pOTC) polypeptide exhibiting and Mr = 39,500 to 40,000 daltons was immunoprecipitated from in vitro translation mixtures of total pea leaf poly(A)+ RNA. The size of the pOTC polypeptide, as compared with mature OTC monomer (36,000 daltons), suggests that a 4 kilodalton N-terminal leader sequence, like that responsible for mitochondrial targeting of the mammalian enzyme, may be involved in organellar import of the plant enzyme.

Comparison of electric and growth responses to excision in cucumber and pea seedlings. II. Long-distance effects are caused by the release of xylem pressure

NASA Technical Reports Server (NTRS)

Stahlberg, R.; Cosgrove, D. J.

1995-01-01

Excision of a growing stem causes local wound responses, such as membrane depolarization and growth inhibition, as well as effects at larger distances from the cut. In this study, cucumber hypocotyls were excised 100 mm below the hook, so that the growing region was beyond the reach of the wound-induced depolarization (up to 40 mm). Even at such a distance, the cut still caused a considerable and rapid drop in the hypocotyl growth rate. This growth response is not a direct wound response because it does not result from the cut-induced depolarization and because it can be simulated by root pressure manipulation (using a pressure chamber). The results indicate that the growth response resulted from the rapid release of the xylem pressure upon excision. To test this conclusion we measured the xylem pressure by connecting a pressure probe to the cut surface of the stem. Xylem pressure (Px) was found to be +10 to +40 kPa in cucumber hypocotyls and -5 to -10 kPa or lower in pea epicotyls. Excision of the cucumber hypocotyl base led to a rapid drop in Px to negative values, whereas excision in pea led to a rapid rise in Px to ambient (zero) pressure. These fast and opposite Px changes parallel the excision-induced changes in growth rate (GR): a decrease in cucumber and a rise in pea. The sign of the endogenous xylem pressure also determined whether excision induced a propagating depolarization in the form of a slow wave potential (SWP). Under normal circumstances pea seedlings generated an SWP upon excision whereas cucumber seedlings failed to do so. When the Px in cucumber hypocotyls was experimentally inverted to negative values by incubating the cumber roots in solutions of NaCN or n-ethylmaleimide, excision caused a propagating depolarization (SWP). The experiment shows that only hydraulic signals in the form of positive Px steps are converted into propagating electric SWP signals. These propagating depolarizations might be causally linked to systemic 'wound' responses, which occur independently of the short-distance or direct wound responses.

The Late Holocene Stratigraphy of an Inlet-Dominated Barrier Island, Pea Island, North Carolina.

NASA Astrophysics Data System (ADS)

Smith, C. G.; Ames, D.; Corbett, D. R.; Culver, S.; Mallinson, D.; Riggs, S. R.; Vance, D.

2002-12-01

Sedimentological, foraminiferal, geochemical, and geophysical data sets as well as aerial photographs have been used to investigate the natural processes (inlet dynamics, ocean/estuarine washover, and sea-level change) responsible for the late Holocene units preserved in the barrier island subsurface at Pea Island National Wildlife Refuge. Historic nautical charts indicate that three inlets characterized Pea Island between early European exploration (1590) and the late 19th century; aerial photographs show New Inlet open in 1932 and 1940. Vibracores (up to 5.5 m) collected along three transects across Pea Island extend our knowledge of the geological evolution of this region to pre-historic times. The section in the longest core (PI01S6) consists of four fining-upwards depositional sequences. The basal unit of each sequence is a bedded, medium to fine, clean quartz sand with increasing concentrations of organic matter (3-4 % detrital and 5-7 % in situ Spartina alterniflora roots) or irregular mud clasts (2-5 cm) to spherical mud balls (1-2 cm) up core. The clean sand units have so far proven to be barren of foraminifera except for a shelly unit at ca. 220 cm below MSL. The foraminiferal assemblage in this unit is of open shelf character (Elphidium excavatum, Hanzawaia strattoni, and Buccella inusitata). A 14C age on a disarticulated Chione cancellata valve from this unit is cal. 930+/-60 BP. The sand grades into a gray, tight mud in the first two sequences and into an inter-laminated mud and in situ peat in the third sequence. The peat contains leaf fragments and rhizomes of the marsh plants Juncus roemarianus, Spartina cynosuroides, and/or Phragmites spp. The peat and muddy sand units contain marsh foraminifera (Trochammina spp., Miliammina fusca, Arenoparrella mexicana), which are also found in modern marsh deposits. A peat sample from the third fining upward sequence (the only one to grade into a true peat) has a 14C age of cal. 395+/-35 BP, cal. 295+/-35 BP, or cal 180+/-40 BP. The four fining-upwards sequences have sharp erosional basal contacts. These deposits appear to reflect back-barrier processes including sequential deposition of flood-tide delta sands and/or sound sands adjacent to marshes. The shelly sands, containing open shelf foraminiferal assemblages, represent oceanic overwash, inlet deposits, or open embayment sands deposited behind a laterally extensive breach in the barrier island. The sequences are capped by the deposits of modern environments that include algal flats, tidal creeks, high and low marshes, back-barrier berms, overwash fans, and aeolian dunes. Several of the modern environments became covered with marsh vegetation after the construction of barrier dune ridges in the late 1930?s.

Spatial and directional variation of growth rates in Arabidopsis root apex: a modelling study.

PubMed

Nakielski, Jerzy; Lipowczan, Marcin

2013-01-01

Growth and cellular organization of the Arabidopsis root apex are investigated in various aspects, but still little is known about spatial and directional variation of growth rates in very apical part of the apex, especially in 3D. The present paper aims to fill this gap with the aid of a computer modelling based on the growth tensor method. The root apex with a typical shape and cellular pattern is considered. Previously, on the basis of two types of empirical data: the published velocity profile along the root axis and dimensions of cell packets formed in the lateral part of the root cap, the displacement velocity field for the root apex was determined. Here this field is adopted to calculate the linear growth rate in different points and directions. The results are interpreted taking principal growth directions into account. The root apex manifests a significant anisotropy of the linear growth rate. The directional preferences depend on a position within the root apex. In the root proper the rate in the periclinal direction predominates everywhere, while in the root cap the predominating direction varies with distance from the quiescent centre. The rhizodermis is distinguished from the neighbouring tissues (cortex, root cap) by relatively high contribution of the growth rate in the anticlinal direction. The degree of growth anisotropy calculated for planes defined by principal growth directions and exemplary cell walls may be as high as 25. The changes in the growth rate variation are modelled.

Biochemical and molecular characterization of a rhizobitoxine-producing Bradyrhizobium from pigeon pea plants.

PubMed

Kanika; Dogra, Tripti; Lata

2010-05-01

Out of a total of 8 bacterial strains isolated from the root nodules of pigeon pea plants grown in arid region, five were identified as rhizobia based on biochemical test and confirmed by 16S rDNA sequencing. PCR based screening for the rtxA gene (involved in biosynthesis of rhizobitoxine) revealed that the gene was present in one strain identified biochemically and genetically as belonging to species Bradyrhizobium (BS KT-24). The strain was resistant to phosphomycin, nalidixic acid, kanamycin, gentamicin and neomycin but sensitive towards streptomycin and spectinomycin. Bioinformatic-tool-guided phylogenetic analysis of rtxA gene revealed its distinctiveness from other known rtxA genes (present in B. japonicum, B. elkanii and Xanthomonas oryzae). The rhizobitoxine producing strain BS KT-24 is considered to exhibit better survival and nodulation protection besides competitiveness for pigeon pea and other legumes grown under abiotic stress and, thus, be a candidate in practical aspect of rhizobitoxine production by rhizobium and its application as rhizobial inoculants.

Fluidity of pea root plasma membranes under altered gravity

NASA Astrophysics Data System (ADS)

Klymchuk, D. O.; Baranenko, V. V.; Vorobyova, T. V.; Dubovoy, V. D.

This investigation aims to determine whether clinorotation 2 rev min of pea Pisum sativum L seedlings induces the alterations in the physical-chemical properties of cellular membranes including the plasma membrane fluidity The last is an important regulator of functional activity of membrane enzymes The plasma membranes were isolated by aqueous two-phase partitioning from roots of 6-day old pea seedlings The membrane fluidity was examined by fluorescence spectroscopy using pyrene probe The plasma membrane vesicles with known protein concentration were added to the incubation buffer to a final concentration of 50 mu g of protein per ml A small amount by 1 mu l of pyrene solution in 2-propanol was added to the incubation mixture to a final probe concentration 5 mu M at constant mixing Fluorescence spectra were measured using a Perkin-Elmer LS-50 spectrofluorometer Perkin-Elmer England Pyrene was excited at 337 nm and fluorescence intensity of monomers I M and excimers I E were measured at 393 and 470 nm respectively The I E I M ratios were 0 081 pm 0 003 and 0 072 pm 0 004 in preparations obtained from clinorotated and the control seedlings respectively This fact indicates that rotation on the clinostat increases the membrane fluidity Compared with controls clinorotated seedlings have also showed a reduced growth and a higher level of total unsaturated fatty acids determined by gas chromatography The factors that influence on the fluidity of membrane lipids in bilayer appear to be the

Circumnutation and its dependence on the gravity response in rice, morning glory and pea plants: verification by spaceflight experiments

NASA Astrophysics Data System (ADS)

Takahashi, Hideyuki; Kobayashi, Akie; Fujii, Nobuharu; Yano, Sachiko; Shimazu, Toru; Kim, Hyejeong; Tomita, Yuuta; Miyazawa, Yutaka

Plant organs display helical growth movement known as circumnutation. This movement helps plant organs find suitable environmental cues. The amplitude, period and shape of the circumnutation differ depending on plant species or organs. Although the mechanism for circumnutation is unclear, it has long been argued whether circumnutation is involved with gravitropic response. Previously, we showed that shoots of weeping morning glory (we1 and we2) are impaired in not only the differentiation of endodermis (gravisensing cells) and gravitropic response, but also winding and circumnutation (Kitazawa et al., PNAS 102: 18742-18747, 2005). Here, we report a reduced circumnutation in the shoots of rice and the roots of pea mutants defective in gravitropic response. Coleoptiles of clinorotated rice seedlings and decapped roots of pea seedlings also showed a reduction of their circumnutational movement. These results suggest that circumnutation is tightly related with gravitropic response. In the proposed spaceflight experiments, “Plant Rotation”, we will verify the hypothesis that circumnutation requires gravity response, by using microgravity environment in KIBO module of the International Space Station. We will grow rice and morning glory plants under both muG and 1G conditions on orbit and monitor their growth by a camera. The downlinked images will be analyzed for the measurements of plant growth and nutational movements. This experiment will enable us to answer the question whether circumnutation depends on gravity response or not.

Characterizing the Physics of Plant Root Gravitropism: A Systems Modeling Approach

DTIC Science & Technology

1999-01-01

with its root directly downward, the root and stem undergo a gravitropic response. Statoliths (gravity-sensing organelles) within the root cap respond...this study is to model the plant root gravitropic response using classical controls and system identification principles. Specific objectives of this

Cloning and expression of a nuclear encoded plastid specific 33 kDa ribonucleoprotein gene (33RNP) from pea that is light stimulated.

PubMed

Reddy, M K; Nair, S; Singh, B N; Mudgil, Y; Tewari, K K; Sopory, S K

2001-01-24

We report the cloning and sequencing of both cDNA and genomic DNA of a 33 kDa chloroplast ribonucleoprotein (33RNP) from pea. The analysis of the predicted amino acid sequence of the cDNA clone revealed that the encoded protein contains two RNA binding domains, including the conserved consensus ribonucleoprotein sequences CS-RNP1 and CS-RNP2, on the C-terminus half and the presence of a putative transit peptide sequence in the N-terminus region. The phylogenetic and multiple sequence alignment analysis of pea chloroplast RNP along with RNPs reported from the other plant sources revealed that the pea 33RNP is very closely related to Nicotiana sylvestris 31RNP and 28RNP and also to 31RNP and 28RNP of Arabidopsis and spinach, respectively. The pea 33RNP was expressed in Escherichia coli and purified to homogeneity. The in vitro import of precursor protein into chloroplasts confirmed that the N-terminus putative transit peptide is a bona fide transit peptide and 33RNP is localized in the chloroplast. The nucleic acid-binding properties of the recombinant protein, as revealed by South-Western analysis, showed that 33RNP has higher binding affinity for poly (U) and oligo dT than for ssDNA and dsDNA. The steady state transcript level was higher in leaves than in roots and the expression of this gene is light stimulated. Sequence analysis of the genomic clone revealed that the gene contains four exons and three introns. We have also isolated and analyzed the 5' flanking region of the pea 33RNP gene.

A polygalacturonase-inhibiting protein with a role in pea defence against the cyst nematode Heterodera goettingiana.

PubMed

Veronico, Pasqua; Melillo, M Teresa; Saponaro, Concetta; Leonetti, Paola; Picardi, Ernesto; Jones, John T

2011-04-01

A cDNA of 312 bp, similar to polygalacturonase-inhibiting proteins (PGIPs), was isolated by cDNA-amplified fragment length polymorphism (cDNA-AFLP) from pea roots infected with the cyst nematode Heterodera goettingiana. The deduced amino acid sequence obtained from the complete Pspgip1 coding sequence was very similar to PGIPs described from several other plant species, and was identical in both MG103738 and Progress 9 genotypes, resistant and susceptible to H. goettingiana, respectively. Reverse transcription-polymerase chain reaction (RT-PCR) expression analysis revealed the differential regulation of the Pspgip1 gene in the two genotypes in response to wounding and nematode challenge. Mechanical wounding induced Pspgip1 expression in MG103738 within 8 h, but this response was delayed in Progress 9. In contrast, the response to nematode infection was more complex. The transcription of Pspgip1 was triggered rapidly in both genotypes, but the expression level returned to levels observed in uninfected plants more quickly in susceptible than in resistant roots. In addition, in situ hybridization showed that Pspgip1 was expressed in the cortical cells damaged as a result of nematode invasion in both genotypes. However, it was specifically localized in the cells bordering the nematode-induced syncytia in resistant roots. This suggests a role for this gene in counteracting nematode establishment inside the root. © 2010 THE AUTHORS. MOLECULAR PLANT PATHOLOGY © 2010 BSPP AND BLACKWELL PUBLISHING LTD.

Osmotic adjustment and the growth response of seven vegetable crops following water-deficit stress. [Phaseolus vulgaris L. ; Beta vulgaris L. ; Abelmoschus esculentus; Pisum sativum L. ; Capsicum annuum L. ; Spinacia oleracea L. ; Lycopersicon esculentum Mill

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wullschleger, S.D.; Oosterhuis, D.M.

Growth-chamber studies were conducted to examine the ability of seven vegetable crops- Blue Lake beam (Phaseolus vulgaris L.) Detroit Dark Red beet (Beta vulgaris L.) Burgundy okra (Abelmoschus esculentus) (Moench), Little Marvel pea (Pisum sativum L), California Wonder bell pepper (Capsicum annuum L), New Zealand spinach (Spinacia oleracea L), and Beefsteak tomato (Lycopersicon esculentum Mill.) - to adjust osmotically in response to water-deficit stress. Water stress was imposed by withholding water for 3 days, and the adjustment of leaf and root osmotic potentials upon relief of the stress and rehydration were monitored with thermocouple psychrometers. Despite similar reductions in leafmore » water potential and stomatal conductance among the species studied reductions in lead water potential an stomatal conductance among the species, crop-specific differences were observed in leak and root osmotic adjustment. Leaf osmotic adjustment was observed for bean, pepper, and tomato following water-deficit stress. Root osmotic adjustment was significant in bean, okra, pea and tomato. Furthermore, differences in leaf and root osmotic adjustment were also observed among five tomato cultivars. Leaf osmotic adjustment was not associated with the maintenance of leaf growth following water-deficit stress, since leaf expansion of water-stressed bean and pepper, two species capable of osmotic adjustment, was similar to that of spinach, which exhibited no leaf osmotic adjustment.« less

Actin microfilaments in presumptive statocytes of root caps and coleoptiles

NASA Technical Reports Server (NTRS)

White, R. G.; Sack, F. D.

1990-01-01

Rhodamine-phalloidin was used to determine the distribution of actin microfilament bundles (mfb) in cells thought to be the site of gravity perception (statocytes) in coleoptiles and root caps of Zea mays and Hordeum vulgare. In coleoptile cells, amyloplasts were usually observed in close proximity to thick mfb, which often appeared to divide into finer mfb adjacent to individual amyloplasts. The nucleus in these cells was surrounded by an extensive network of mfb, which were connected to thicker transvacuolar mfb. Columella cells of the root cap contained an extensive reticulum of fine mfb throughout the protoplast, but lacked the much thicker mfb seen in coleoptile cells. The distribution and extent of mfb observed in fixed cells correlates with patterns of streaming and amyloplast movement seen in living cells. A possible role for actin mfb in the perception of gravity is discussed.

Effect of cationic plastoquinone SkQ1 on electron transfer reactions in chloroplasts and mitochondria from pea seedlings.

PubMed

Samuilov, V D; Kiselevsky, D B

2015-04-01

Plastoquinone bound with decyltriphenylphosphonium cation (SkQ1) penetrating through the membrane in nanomolar concentrations inhibited H2O2 generation in cells of epidermis of pea seedling leaves that was detected by the fluorescence of 2',7'-dichlorofluorescein. Photosynthetic electron transfer in chloroplasts isolated from pea leaves is suppressed by SkQ1 at micromolar concentrations: the electron transfer in chloroplasts under the action of photosystem II or I (with silicomolybdate or methyl viologen as electron acceptors, respectively) is more sensitive to SkQ1 than under the action of photosystem II + I (with ferricyanide or p-benzoquinone as electron acceptors). SkQ1 reduced by borohydride is oxidized by ferricyanide, p-benzoquinone, and, to a lesser extent, by silicomolybdate, but not by methyl viologen. SkQ1 is not effective as an electron acceptor supporting O2 evolution from water in illuminated chloroplasts. The data on suppression of photosynthetic O2 evolution or consumption show that SkQ1, similarly to phenazine methosulfate, causes conversion of the chloroplast redox-chain from non-cyclic electron transfer mode to the cyclic mode without O2 evolution. Oxidation of NADH or succinate in mitochondria isolated from pea roots is stimulated by SkQ1.

QTL meta-analysis provides a comprehensive view of loci controlling partial resistance to Aphanomyces euteiches in four sources of resistance in pea

USDA-ARS?s Scientific Manuscript database

More knowledge about diversity of Quantitative Trait Loci (QTL) controlling polygenic disease resistance in natural genetic variation of crop species is required for durably improving plant genetic resistances to pathogens. Polygenic partial resistance to Aphanomyces root rot, due to Aphanomcyces eu...

Uptake and Accumulation of the Herbicides Chlorsulfuron and Clopyralid in Excised Pea Root Tissue 1

PubMed Central

Devine, Malcolm D.; Bestman, Hank D.; Vanden Born, William H.

1987-01-01

The herbicides chlorsulfuron and clopyralid were taken up rapidly by excised pea root tissue and accumulated in the tissue to concentrations ten and four times those in the external medium, respectively. Uptake was related linearly to external herbicide concentration over a wide concentration range, implying that transport across the membrane is by nonfacilitated diffusion. Uptake of both compounds was influenced by pH, with greatest uptake at low pH. The pH dependence of uptake suggests that the herbicides (both of which are weak acids) are transported across the plasma membrane in the undissociated form, and accumulate in the cytoplasm by an ion trap mechanism. Most of the absorbed herbicide effluxed from the tissue when it was transferred to herbicide-free buffer, indicating that the accumulation was not due to irreversible binding. Consequently, both herbicides remain available for transfer to the phloem. These results can explain the high reported phloem mobility of clopyralid in intact plants. The low phloem mobility of chlorsulfuron must be accounted for by factors that override its ability to accumulate in the symplast. PMID:16665689

The possible involvement of root-cap mucilage in gravitropism and calcium movement across root tips of Allium cepa L

NASA Technical Reports Server (NTRS)

Moore, R.; Fondren, W. M.

1986-01-01

Roots of Allium cepa L. grown in aerated water elongate rapidly, but are not graviresponsive. These roots (1) possess extensive columella tissues comprised of cells containing numerous sedimented amyloplasts, (2) lack mucilage on their tips, and (3) are characterized by a weakly polar movement of calcium (Ca) across their tips. Placing roots in humid air correlates positively with the (1) onset of gravicurvature, (2) appearance of mucilage on tips of the roots, and (3) onset of the ability to transport Ca polarly to the lower side of the root tip. Gravicurvature of roots previously submerged in aerated water is more rapid when roots are oriented vertically for 1-2 h in humid air prior to being oriented horizontally. The more rapid gravicurvature of these roots correlates positively with the accumulation of mucilage at the tips of roots during the time the roots are oriented vertically. Therefore, the onset of gravicurvature and the ability of roots to transport Ca to the lower sides of their tips correlate positively with the presence of mucilage at their tips. These results suggest that mucilage may be important for the transport of Ca across root caps.

Effects of norflurazon, an inhibitor of carotenogenesis, on abscisic acid and xanthoxin in the caps of gravistimulated maize roots

NASA Technical Reports Server (NTRS)

Feldman, L. J.; Sun, P. S.

1986-01-01

Maize seeds were germinated in the dark in the presence of the carotenoid synthesis inhibitor norflurazon and the levels of abscisic acid, xanthoxin and total carotenoids were measured in the root cap and in the adjacent 1.5 mm segment. In norflurazon-treated roots abscisic acid levels were markedly reduced, but an increase occurred in the levels of xanthoxin, a compound structurally and physiologically similar to abscisic acid. In the cultivar of maize (Zea mays L. cv. Merit) used for this work, brief illumination of the root is required for gravitropic curving. Following illumination both control and norflurazon-treated roots showed normal gravitropic curvature; however, the rate of curvature was delayed in norflurazon-treated roots. Our data from norflurazon-treated roots are consistent with a role for xanthoxin in maize root gravitropism. The increase in xanthoxin in the presence of an inhibitor of carotenoid synthesis suggests that xanthoxin and abscisic acid originate, at least in part, via different metabolic pathways.

Biostimulant action of a plant-derived protein hydrolysate produced through enzymatic hydrolysis

PubMed Central

Colla, Giuseppe; Rouphael, Youssef; Canaguier, Renaud; Svecova, Eva; Cardarelli, Mariateresa

2014-01-01

The aim of this study was to evaluate the biostimulant action (hormone like activity, nitrogen uptake, and growth stimulation) of a plant-derived protein hydrolysate by means of two laboratory bioassays: a corn (Zea mays L.) coleoptile elongation rate test (Experiment 1), a rooting test on tomato cuttings (Experiment 2); and two greenhouse experiments: a dwarf pea (Pisum sativum L.) growth test (Experiment 3), and a tomato (Solanum lycopersicum L.) nitrogen uptake trial (Experiment 4). Protein hydrolysate treatments of corn caused an increase in coleoptile elongation rate when compared to the control, in a dose-dependent fashion, with no significant differences between the concentrations 0.75, 1.5, and 3.0 ml/L, and inodole-3-acetic acid treatment. The auxin-like effect of the protein hydrolysate on corn has been also observed in the rooting experiment of tomato cuttings. The shoot, root dry weight, root length, and root area were significantly higher by 21, 35, 24, and 26%, respectively, in tomato treated plants with the protein hydrolysate at 6 ml/L than untreated plants. In Experiment 3, the application of the protein hydrolysate at all doses (0.375, 0.75, 1.5, and 3.0 ml/L) significantly increased the shoot length of the gibberellin-deficient dwarf pea plants by an average value of 33% in comparison with the control treatment. Increasing the concentration of the protein hydrolysate from 0 to 10 ml/L increased the total dry biomass, SPAD index, and leaf nitrogen content by 20.5, 15, and 21.5%, respectively. Thus the application of plant-derived protein hydrolysate containing amino acids and small peptides elicited a hormone-like activity, enhanced nitrogen uptake and consequently crop performances. PMID:25250039

X-Ray Microanalysis of Human Cementum

NASA Astrophysics Data System (ADS)

Alvarez-Pérez, Marco Antonio; Alvarez-Fregoso, Octavio; Ortiz-López, Jaime; Arzate, Higinio

2005-08-01

An energy dispersive x-ray microanalysis study was performed throughout the total length of cementum on five impacted human teeth. Mineral content of calcium, phosphorous, and magnesium were determined with an electron probe from the cemento-enamel junction to the root apex on the external surface of the cementum. The concentration profiles for calcium, phosphorous, and magnesium were compared by using Ca/P and Mg/Ca atomic percent ratio. Our findings demonstrated that the Ca/P ratio at the cemento-enamel junction showed the highest values (1.8 2.2). However, the area corresponding to the acellular extrinsic fiber cementum (AEFC) usually located on the coronal one-third of the root surface showed a Ca/P media value of 1.65. Nevertheless, on the area representing the fulcrum of the root there is an abrupt change in the Ca/P ratio, which decreases to 1.3. Our results revealed that Mg2+ distribution throughout the length of human cementum reached its maximum Mg/Ca ratio value of 1.3 1.4 at.% around the fulcrum of the root and an average value of 0.03%. A remarkable finding was that the Mg/Ca ratio pattern distribution showed that in the region where the Ca/P ratio showed a decreasing tendency, the Mg/Ca ratio reached its maximum value, showing a negative correlation. In conclusion, this study has established that clear compositional differences exist between AEFC and cellular mixed stratified cementum varieties and adds new knowledge about Mg2+ distribution and suggests its provocative role regulating human cementum metabolism.

Root graviresponsiveness and cellular differentiation in wild-type and a starchless mutant of Arabidopsis thaliana

NASA Technical Reports Server (NTRS)

Moore, R.

1989-01-01

Primary roots of a starchless mutant of Arabidopsis thaliana L. are strongly graviresponsive despite lacking amyloplasts in their columella cells. The ultrastructures of calyptrogen and peripheral cells in wild-type as compared to mutant seedlings are not significantly different. The largest difference in cellular differentiation in caps of mutant and wild-type roots is the relative volume of plastids in columella cells. Plastids occupy 12.3% of the volume of columella cells in wild-type seedlings, but only 3.69% of columella cells in mutant seedlings. These results indicate that: (1) amyloplasts and starch are not necessary for root graviresponsiveness; (2) the increase in relative volume of plastids that usually accompanies differentiation of columella cells is not necessary for root graviresponsiveness; and (3) the absence of starch and amyloplasts does not affect the structure of calyptrogen (i.e. meristematic) and secretory (i.e. peripheral) cells in root caps. These results are discussed relative to proposed models for root gravitropism.

Accumulation and localization of extensin protein in apoplast of pea root nodule under aluminum stress.

PubMed

Sujkowska-Rybkowska, Marzena; Borucki, Wojciech

2014-12-01

Cell wall components such as hydroxyproline-rich glycoproteins (HRGPs, extensins) have been proposed to be involved in aluminum (Al) resistance mechanisms in plants. We have characterized the distribution of extensin in pea (Pisum sativum L.) root nodules apoplast under short (for 2 and 24h) Al stress. Monoclonal antibodie LM1 have been used to locate extensin protein epitope by immunofluorescence and immunogold labeling. The nodules were shown to respond to Al stress by thickening of plant and infection thread (IT) walls and disturbances in threads growth and bacteria endocytosis. Immunoblot results indicated the presence of a 17-kDa band specific for LM1. Irrespective of the time of Al stress, extensin content increased in root nodules. Further observation utilizing fluorescence and transmission electron microscope showed that LM1 epitope was localized in walls and intercellular spaces of nodule cortex tissues and in the infection threads matrix. Al stress in nodules appears to be associated with higher extensin accumulation in matrix of enlarged thick-walled ITs. In addition to ITs, thickened walls and intercellular spaces of nodule cortex were also associated with intense extensin accumulation. These data suggest that Al-induced extensin accumulation in plant cell walls and ITs matrix may have influence on the process of IT growth and tissue and cell colonization by Rhizobium bacteria. Copyright © 2014 Elsevier Ltd. All rights reserved.

Efficient production of human acidic fibroblast growth factor in pea (Pisum sativum L.) plants by agroinfection of germinated seeds

PubMed Central

2011-01-01

Background For efficient and large scale production of recombinant proteins in plants transient expression by agroinfection has a number of advantages over stable transformation. Simple manipulation, rapid analysis and high expression efficiency are possible. In pea, Pisum sativum, a Virus Induced Gene Silencing System using the pea early browning virus has been converted into an efficient agroinfection system by converting the two RNA genomes of the virus into binary expression vectors for Agrobacterium transformation. Results By vacuum infiltration (0.08 Mpa, 1 min) of germinating pea seeds with 2-3 cm roots with Agrobacteria carrying the binary vectors, expression of the gene for Green Fluorescent Protein as marker and the gene for the human acidic fibroblast growth factor (aFGF) was obtained in 80% of the infiltrated developing seedlings. Maximal production of the recombinant proteins was achieved 12-15 days after infiltration. Conclusions Compared to the leaf injection method vacuum infiltration of germinated seeds is highly efficient allowing large scale production of plants transiently expressing recombinant proteins. The production cycle of plants for harvesting the recombinant protein was shortened from 30 days for leaf injection to 15 days by applying vacuum infiltration. The synthesized aFGF was purified by heparin-affinity chromatography and its mitogenic activity on NIH 3T3 cells confirmed to be similar to a commercial product. PMID:21548923

Genotypic and symbiotic diversity of Rhizobium populations associated with cultivated lentil and pea in sub-humid and semi-arid regions of Eastern Algeria.

PubMed

Riah, Nassira; Béna, Gilles; Djekoun, Abdelhamid; Heulin, Karine; de Lajudie, Philippe; Laguerre, Gisèle

2014-07-01

The genetic structure of rhizobia nodulating pea and lentil in Algeria, Northern Africa was determined. A total of 237 isolates were obtained from root nodules collected on lentil (Lens culinaris), proteaginous and forage pea (Pisum sativum) growing in two eco-climatic zones, sub-humid and semi-arid, in Eastern Algeria. They were characterised by PCR-restriction fragment length polymorphism (RFLP) of the 16S-23S rRNA intergenic region (IGS), and the nodD-F symbiotic region. The combination of these haplotypes allowed the isolates to be clustered into 26 distinct genotypes, and all isolates were classified as Rhizobium leguminosarum. Symbiotic marker variation (nodD-F) was low but with the predominance of one nod haplotype (g), which had been recovered previously at a high frequency in Europe. Sequence analysis of the IGS further confirmed its high variability in the studied strains. An AMOVA analysis showed highly significant differentiation in the IGS haplotype distribution between populations from both eco-climatic zones. This differentiation was reflected by differences in dominant genotype frequencies. Conversely, no host plant effect was detected. The nodD gene sequence-based phylogeny suggested that symbiotic gene diversity in pea and lentil nodulating rhizobial populations in Algeria was low compared to that reported elsewhere in the world. Copyright © 2014 Elsevier GmbH. All rights reserved.

Hypocrea lixii, novel endophytic fungi producing anticancer agent cajanol, isolated from pigeon pea (Cajanus cajan [L.] Millsp.).

PubMed

Zhao, J; Li, C; Wang, W; Zhao, C; Luo, M; Mu, F; Fu, Y; Zu, Y; Yao, M

2013-07-01

The aim was to isolate, identify and characterize endophytes from pigeon pea (Cajanus cajan [L.] Millsp.), as novel producer of cajanol and its in vitro cytotoxicity assay. Isolation, identification and characterization of novel endophytes producing cajanol from the roots of pigeon pea were investigated. The endophytes were identified as Hypocrea lixii by morphological and molecular methods. Cajanol produced by endophytes were quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). R-18 produced the highest levels of cajanol (322·4 ± 10·6 μg l(-1) or 102·8 ± 6·9 μg g(-1) dry weight of mycelium) after incubation for 7 days. The cytotoxicity towards human lung carcinoma cells (A549) of fungal cajanol was investigated in vitro. First, a novel endophyte Hypocrea lixii, producing anticancer agent cajanol, was isolated from the host pigeon pea (Cajanus cajan [L.] Millsp.). Fungal cajanol possessed stronger cytotoxicity activity towards A549 cells in time- and dose-dependent manners. This endophyte is a potential handle for scientific and commercial exploitation, and it could provide a promising alterative approach for large-scale production of cajanol to satisfy new anticancer drug development. Journal of Applied Microbiology © 2013 The Society for Applied Microbiology.

Root architecture simulation improves the inference from seedling root phenotyping towards mature root systems

PubMed Central

Zhao, Jiangsan; Rewald, Boris; Leitner, Daniel; Nagel, Kerstin A.; Nakhforoosh, Alireza

2017-01-01

Abstract Root phenotyping provides trait information for plant breeding. A shortcoming of high-throughput root phenotyping is the limitation to seedling plants and failure to make inferences on mature root systems. We suggest root system architecture (RSA) models to predict mature root traits and overcome the inference problem. Sixteen pea genotypes were phenotyped in (i) seedling (Petri dishes) and (ii) mature (sand-filled columns) root phenotyping platforms. The RSA model RootBox was parameterized with seedling traits to simulate the fully developed root systems. Measured and modelled root length, first-order lateral number, and root distribution were compared to determine key traits for model-based prediction. No direct relationship in root traits (tap, lateral length, interbranch distance) was evident between phenotyping systems. RootBox significantly improved the inference over phenotyping platforms. Seedling plant tap and lateral root elongation rates and interbranch distance were sufficient model parameters to predict genotype ranking in total root length with an RSpearman of 0.83. Parameterization including uneven lateral spacing via a scaling function substantially improved the prediction of architectures underlying the differently sized root systems. We conclude that RSA models can solve the inference problem of seedling root phenotyping. RSA models should be included in the phenotyping pipeline to provide reliable information on mature root systems to breeding research. PMID:28168270

Spatial separation of light perception and growth response in maize root phototropism.

PubMed

Mullen, J L; Wolverton, C; Ishikawa, H; Hangarter, R P; Evans, M L

2002-09-01

Although the effects of gravity on root growth are well known and interactions between light and gravity have been reported, details of root phototropic responses are less documented. We used high-resolution image analysis to study phototropism in primary roots of Zea mays L. Similar to the location of perception in gravitropism, the perception of light was localized in the root cap. Phototropic curvature away from the light, on the other hand, developed in the central elongation zone, more basal than the site of initiation of gravitropic curvature. The phototropic curvature saturated at approximately 10 micromoles m-2 s-1 blue light with a peak curvature of 29 +/- 4 degrees, in part due to induction of positive gravitropism following displacement of the root tip from vertical during negative phototropism. However, at higher fluence rates, development of phototropic curvature is arrested even if gravitropism is avoided by maintaining the root cap vertically using a rotating feedback system. Thus continuous illumination can cause adaptation in the signalling pathway of the phototropic response in roots.

Intensity of hydrostimulation for the induction of root hydrotropism and its sensing by the root cap

NASA Technical Reports Server (NTRS)

Takahashi, H.; Scott, T. K.

1993-01-01

Roots of Pisum sativum L. and Zea mays L. were exposed to different moisture gradients established by placing both wet cheesecloth (hydrostimulant) and saturated aqueous solutions of various salts in a closed chamber. Atmospheric conditions with different relative humidity (RH) in a range between 98 and 86% RH were obtained at root level, 2 to 3mm from the water-saturated hydrostimulant. Roots of Silver Queen corn placed vertically with the tips down curved sideways toward the hydrostimulant in response to approximately 94% RH but did not respond positively to RH higher than approximately 95%. The positive hydrotropic response increased linearly as RH was lowered from 95 to 90%. A maximum response was observed at RH between 90 and 86%. However, RH required for the induction of hydrotropism as well as the responsiveness differed among plant species used; gravitropically sensitive roots appeared to require a somewhat greater moisture gradient for the induction of hydrotropism. Decapped roots of corn failed to curve hydrotropically, suggesting the root cap as a major site of hydrosensing.

Spatial separation of light perception and growth response in maize root phototropism

NASA Technical Reports Server (NTRS)

Mullen, J. L.; Wolverton, C.; Ishikawa, H.; Hangarter, R. P.; Evans, M. L.

2002-01-01

Although the effects of gravity on root growth are well known and interactions between light and gravity have been reported, details of root phototropic responses are less documented. We used high-resolution image analysis to study phototropism in primary roots of Zea mays L. Similar to the location of perception in gravitropism, the perception of light was localized in the root cap. Phototropic curvature away from the light, on the other hand, developed in the central elongation zone, more basal than the site of initiation of gravitropic curvature. The phototropic curvature saturated at approximately 10 micromoles m-2 s-1 blue light with a peak curvature of 29 +/- 4 degrees, in part due to induction of positive gravitropism following displacement of the root tip from vertical during negative phototropism. However, at higher fluence rates, development of phototropic curvature is arrested even if gravitropism is avoided by maintaining the root cap vertically using a rotating feedback system. Thus continuous illumination can cause adaptation in the signalling pathway of the phototropic response in roots.

The role of calcium and calmodulin in the response of roots to gravity

NASA Technical Reports Server (NTRS)

Evans, Michael L.

1992-01-01

There is general agreement that, in roots, the primary detection of the gravitropic signal occurs in the columella cells of the cap and that this results in the generation of a signal that moves into the elongation zone causing the asymmetric growth that leads to downward curvature. Recent work has generated considerable evidence that indicates that auxin is the ultimate mediator of differential growth during root (and shoot) gravitropism. Our studies of the time course of curvature, auxin redistribution and/or adaptation, and electrical potential changes in maize roots have led to the following generalizations: (1) downward curvature begins 18 to 32 min following gravistimulation; (2) asymmetric auxin redistribution across the root cap begins at about the same time as curvature or perhaps slight earlier; (3) there is a lag of approx. 15 min in the response of roots to applied auxin; and (4) gravi-induced changes in intracellular potentials of cortical cells within the elongation zone occur within 30 s following stimulation.

Gravity-regulated differential auxin transport from columella to lateral root cap cells

NASA Technical Reports Server (NTRS)

Ottenschlager, Iris; Wolff, Patricia; Wolverton, Chris; Bhalerao, Rishikesh P.; Sandberg, Goran; Ishikawa, Hideo; Evans, Mike; Palme, Klaus

2003-01-01

Gravity-induced root curvature has long been considered to be regulated by differential distribution of the plant hormone auxin. However, the cells establishing these gradients, and the transport mechanisms involved, remain to be identified. Here, we describe a GFP-based auxin biosensor to monitor auxin during Arabidopsis root gravitropism at cellular resolution. We identify elevated auxin levels at the root apex in columella cells, the site of gravity perception, and an asymmetric auxin flux from these cells to the lateral root cap (LRC) and toward the elongation zone after gravistimulation. We differentiate between an efflux-dependent lateral auxin transport from columella to LRC cells, and an efflux- and influx-dependent basipetal transport from the LRC to the elongation zone. We further demonstrate that endogenous gravitropic auxin gradients develop even in the presence of an exogenous source of auxin. Live-cell auxin imaging provides unprecedented insights into gravity-regulated auxin flux at cellular resolution, and strongly suggests that this flux is a prerequisite for root gravitropism.

Isolation of Nuclei and Nucleoli.

PubMed

Pendle, Alison F; Shaw, Peter J

2017-01-01

Here we describe methods for producing nuclei from Arabidopsis suspension cultures or root tips of Arabidopsis, wheat, or pea. These methods could be adapted for other species and cell types. The resulting nuclei can be further purified for use in biochemical or proteomic studies, or can be used for microscopy. We also describe how the nuclei can be used to obtain a preparation of nucleoli.

40 CFR 180.205 - Paraquat; tolerances for residues.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., sugar, tops 0.05 Berry group 13 0.05 Cacao bean, bean 0.05 Carrot, roots 0.05 Cattle, fat 0.05 Cattle, kidney 0.5 Cattle, meat 0.05 Cattle, meat byproducts, except kidney 0.05 Coffee, bean, green 0.05 Corn..., green 0.05 Papaya 0.05 Passionfruit 0.2 Pea and bean, dried shelled, except soybean, subgroup 6C, except...

40 CFR 180.205 - Paraquat; tolerances for residues.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., sugar, tops 0.05 Berry group 13 0.05 Cacao bean, bean 0.05 Carrot, roots 0.05 Cattle, fat 0.05 Cattle, kidney 0.5 Cattle, meat 0.05 Cattle, meat byproducts, except kidney 0.05 Coffee, bean, green 0.05 Corn..., green 0.05 Papaya 0.05 Passionfruit 0.2 Pea and bean, dried shelled, except soybean, subgroup 6C, except...

Application of Computer-Aided Tomography (CT) Technology to Visually Compare Belowground Components of Salt Marshes in Jamaica Bay and Long Island, New York

EPA Science Inventory

Using CT imaging, we found that rapidly deteriorating marshes in Jamaica Bay had significantly less belowground mass and abundance of coarse roots and rhizomes at depth (< 10 cm) compared to more stable areas in the Jamaica Bay Estuary. In addition, the rhizome diameters and pea...

Effects of heavy metals on the absorbance and reflectance spectra of plants

NASA Technical Reports Server (NTRS)

Horler, D. N. H.; Barber, J.; Barringer, A. R.

1980-01-01

The spectral responses of plants to various concentrations of heavy metals in their rooting media are investigated in relation to the application of remote sensing methods to the detection of vegetation under stress. Absorption photometry of chloroplasts, measurements of metal and chlorophyll concentrations and reflectance spectrometry were performed on leaves of pea, sunflower and soybean plants grown under greenhouse conditions with the addition of various concentrations of Cd, Cu, Pb and Zn to their rooting media and on leaves of oak trees growing naturally in an area of a copper-arsenic mineralization. Under laboratory conditions, the most general effect observed was growth inhibition and ultimately death, with pea plants also exhibiting changes of chlorophyll a/ chlorophyll b ratios with Cd and Cu and reflectance increases in the visible and decreases in the infrared. Although results for other species indicate that reflectance effects are dependent on species, correlations between reflectance and metal exposure is confirmed by the field investigations. It is concluded that a remote sensing system would be improved by the inclusion of bands around 1.65 and 2.20 microns to detect soil mineralization from plant spectra.

Light regulates attachment, exopolysaccharide production, and nodulation in Rhizobium leguminosarum through a LOV-histidine kinase photoreceptor

PubMed Central

Bonomi, Hernán R.; Posadas, Diana M.; Paris, Gastón; Carrica, Mariela del Carmen; Frederickson, Marcus; Pietrasanta, Lía Isabel; Bogomolni, Roberto A.; Zorreguieta, Angeles; Goldbaum, Fernando A.

2012-01-01

Rhizobium leguminosarum is a soil bacterium that infects root hairs and induces the formation of nitrogen-fixing nodules on leguminous plants. Light, oxygen, and voltage (LOV)-domain proteins are blue-light receptors found in higher plants and many algae, fungi, and bacteria. The genome of R. leguminosarum bv. viciae 3841, a pea-nodulating endosymbiont, encodes a sensor histidine kinase containing a LOV domain at the N-terminal end (R-LOV-HK). R-LOV-HK has a typical LOV domain absorption spectrum with broad bands in the blue and UV-A regions and shows a truncated photocycle. Here we show that the R-LOV-HK protein regulates attachment to an abiotic surface and production of flagellar proteins and exopolysaccharide in response to light. Also, illumination of bacterial cultures before inoculation of pea roots increases the number of nodules per plant and the number of intranodular bacteroids. The effects of light on nodulation are dependent on a functional lov gene. The results presented in this work suggest that light, sensed by R-LOV-HK, is an important environmental factor that controls adaptive responses and the symbiotic efficiency of R. leguminosarum. PMID:22773814

Mitochondrial ultrastructure and tissue respiration of pea leaves under clinorotation

NASA Astrophysics Data System (ADS)

Brykov, Vasyl

2016-07-01

Respiration is essential for growth, maintenance, and carbon balance of all plant cells. Mitochondrial respiration in plants provides energy for biosynthesis, and its balance with photosynthesis determines the rate of plant biomass accumulation (production). Mitochondria are not only the energetic organelles in a cell but they play an essential regulatory role in many basic cellular processes. As plants adapt to real and simulated microgravity, it is very important to understand the state of mitochondria in these conditions. Disturbance of respiratory metabolism can significantly affect the productivity of plants in long-term space flights. We have established earlier that the rate of respiration in root apices of pea etiolated seedlings rose after 7 days of clinorotation. These data indicate the oxygen increased requirement by root apices under clinorotation, that confirms the necessity of sufficient substrate aeration in space greenhouses to provide normal respiratory metabolism and supply of energy for root growth. In etiolated seedlings, substrate supply of mitochondria occurs at the expense of the mobilization of cotyledon nutrients. A goal of our work was to study the ultrastructure and respiration of mitochondria in pea leaves after 12 days of clinorotation during (2 rpm/min). Plants grew at a light level of 180 μµmol m ^{-2} s ^{-1} PAR and a photoperiod of 16 h light/4 h dark. It was showed an essential increase in the mitochondrion area on 53% in palisade parenchyma cells at the sections. Such phenomenon can not be described as swelling of mitochondria, since enlarged mitochondria contained a more quantity of crista 1.76 times. In addition, the cristae total area per organelle also increased in comparison with that in control. An increase in a size of mitochondria in the experimental conditions is supposed to occur by a partial alteration of the chondriom. Thus, a size of 49% mitochondria in control was 0.1 - 0.3 μµm ^{2}, whereas only 26% mitochondria have a similar size under clinorotation. Described changes in the mitochondrion ultrastructure under clinorotation were accompanied with rising of mitochondrial respiration on 17%. These data indicate that mitochondria in both root and leaf cells are sensitive to the simulated microgravity influence. That is why, a further research of plant energetic metabolism during plant growth in real and simulated microgravity has to be in progress.

Patterns of auxin and abscisic acid movement in the tips of gravistimulated primary roots of maize

NASA Technical Reports Server (NTRS)

Young, L. M.; Evans, M. L.

1996-01-01

Because both abscisic acid (ABA) and auxin (IAA) have been suggested as possible chemical mediators of differential growth during root gravitropism, we compared with redistribution of label from applied 3H-IAA and 3H-ABA during maize root gravitropism and examined the relative basipetal movement of 3H-IAA and 3H-ABA applied to the caps of vertical roots. Lateral movement of 3H-ABA across the tips of vertical roots was non-polar and about 2-fold greater than lateral movement of 3H-IAA (also non-polar). The greater movement of ABA was not due to enhanced uptake since the uptake of 3H-IAA was greater than that of 3H-ABA. Basipetal movement of label from 3H-IAA or 3H-ABA applied to the root cap was determined by measuring radioactivity in successive 1 mm sections behind the tip 90 minutes after application. ABA remained largely in the first mm (point of application) whereas IAA was concentrated in the region 2-4 mm from the tip with substantial levels found 7-8 mm from the tip. Pretreatment with inhibitors of polar auxin transport decreased both gravicurvature and the basipetal movement of IAA. When roots were placed horizontally, the movement of 3H-IAA from top to bottom across the cap was enhanced relative to movement from bottom to top whereas the pattern of movement of label from 3H-ABA was unaffected. These results are consistent with the hypothesis that IAA plays a role in root gravitropism but contrary to the idea that gravi-induced asymmetric distribution of ABA contributes to the response.

Seed development, seed germination and seedling growth in the R50 (sym16) pea mutant are not directly linked to altered cytokinin homeostasis.

PubMed

Long, Chengli; Held, Mark; Hayward, Allison; Nisler, Jaroslav; Spíchal, Lukas; Neil Emery, R J; Moffatt, Barbara A; Guinel, Frédérique C

2012-06-01

R50 (sym16) is a pea nodulation mutant that accumulates cytokinin (CK) in its vegetative organs. Total CK content increases as the plant ages because of the low activity of the enzyme cytokinin oxidase/dehydrogenase (CKX) responsible for CK degradation. R50 exhibits a large seed with high relative water content, and its seedling establishes itself slowly. Whether these two traits are linked to abnormal CK levels was considered here. R50 was found to have a similar germination rate but a much slower epicotyl emergence than Sparkle, its wild-type (WT). At the onset of emergence, the starch grains in R50 cotyledons were larger than those of WT; furthermore, they did not degrade as fast as in WT because of low amylase activity. No differences between the pea lines were observed in the CK forms identified during seed embryogenesis. However, while CK content compared to that of WT was reduced early in R50 embryogenesis, it was elevated later on in its dry seeds where CKX activity was low, although CKX transcript abundance remained high. Transcripts of the two known PsCKX isoforms exhibited tissue- and development-specific profiles with no detectable PsCKX2 expression in cotyledons. There were more of both transcripts in R50 roots than in WT roots, but less of PsCKX2 than PsCKX1 in R50 shoots compared to WT shoots. Thus, although there is a definite CKX post-transcriptional defect in R50 dry seeds, an abnormal CK homeostasis is not the basis of the delay in R50 seedling establishment, which we linked to abnormal amylase activity early in development. Copyright © Physiologia Plantarum 2012.

Shoot to root communication is necessary to control the expression of iron-acquisition genes in Strategy I plants.

PubMed

García, María J; Romera, Francisco J; Stacey, Minviluz G; Stacey, Gary; Villar, Eduardo; Alcántara, Esteban; Pérez-Vicente, Rafael

2013-01-01

Previous research showed that auxin, ethylene, and nitric oxide (NO) can activate the expression of iron (Fe)-acquisition genes in the roots of Strategy I plants grown with low levels of Fe, but not in plants grown with high levels of Fe. However, it is still an open question as to how Fe acts as an inhibitor and which pool of Fe (e.g., root, phloem, etc.) in the plant acts as the key regulator for gene expression control. To further clarify this, we studied the effect of the foliar application of Fe on the expression of Fe-acquisition genes in several Strategy I plants, including wild-type cultivars of Arabidopsis [Arabidopsis thaliana (L.) Heynh], pea [Pisum sativum L.], tomato [Solanum lycopersicon Mill.], and cucumber [Cucumis sativus L.], as well as mutants showing constitutive expression of Fe-acquisition genes when grown under Fe-sufficient conditions [Arabidopsis opt3-2 and frd3-3, pea dgl and brz, and tomato chln (chloronerva)]. The results showed that the foliar application of Fe blocked the expression of Fe-acquisition genes in the wild-type cultivars and in the frd3-3, brz, and chln mutants, but not in the opt3-2 and dgl mutants, probably affected in the transport of a Fe-related repressive signal in the phloem. Moreover, the addition of either ACC (ethylene precursor) or GSNO (NO donor) to Fe-deficient plants up-regulated the expression of Fe-acquisition genes, but this effect did not occur in Fe-deficient plants sprayed with foliar Fe, again suggesting the existence of a Fe-related repressive signal moving from leaves to roots.

Biological activities of indoleacetylamino acids and their use as auxins in tissue culture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hangarter, R.P.; Peterson, M.D.; Good, N.E.

1980-05-01

The auxin activities of a number of indoleacetylamino acid conjugates have been determined in three test systems: growth of tomato hypocotyl explants (Lycopersicon esculentum Mill. cv. Marglobe); growth of tobacco callus cultures (Nicotiana tabacum L. cv. Wisconsin 38); and ethylene production from pea stems (Pisum sativum L. cv. Alaska). The activities of the conjugates differ greatly depending on the amino acid moiety. Indoleacetyl-L-alanine supports rapid callus growth from the tomato hypocotyls while inhibiting growth of shoots and roots. Indoleacetlyglycine behaves in a similar manner but is somewhat less effective in supporting callus growth and in inhibiting growth of shoots andmore » roots. Indoleacetylglycine behaves in a similar manner but is somewhat less effective in supporting callus growth and in inhibiting shoot formation. The other amino acid conjugates tested (valine, leucine, aspartic acid, threonine, methionine, phenylalanine, and proline) support shoot formation without supporting root formation or much callus growth. The tobacco callus system, which forms abundant shoots in the presence or absence of free indoleacetic acid, produces only rapid undifferentiated growth in the presence of indoleacetyl-L-alanine and indoleacetylglycine. The other conjugates inhibit shoot formatin weakly if at all. Most of the conjugates induce sustained ethylene production from the pea stems but at rates well below the initial rates observed with free indoleacetic acid. Many, but not all of the effects of conjugates such as indoleacetyl-L-alanine can be mimicked by frequent renewals of the supply of free indoleacetic acid.« less

Aluminum Toxicity Is Associated with Mitochondrial Dysfunction and the Production of Reactive Oxygen Species in Plant Cells1

PubMed Central

Yamamoto, Yoko; Kobayashi, Yukiko; Devi, S. Rama; Rikiishi, Sanae; Matsumoto, Hideaki

2002-01-01

Potential mechanisms of Al toxicity measured as Al-induced inhibition of growth in cultured tobacco cells (Nicotiana tabacum, nonchlorophyllic cell line SL) and pea (Pisum sativum) roots were investigated. Compared with the control treatment without Al, the accumulation of Al in tobacco cells caused instantaneously the repression of mitochondrial activities [monitored by the reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide and the uptake of Rhodamine 123] and, after a lag of about 12 h, triggered reactive oxygen species (ROS) production, respiration inhibition, ATP depletion, and the loss of growth capability almost simultaneously. The presence of an antioxidant, butylated hydroxyanisol, during Al treatment of SL cells prevented not only ROS production but also ATP depletion and the loss of growth capability, suggesting that the Al-triggered ROS production seems to be a cause of ATP depletion and the loss of growth capability. Furthermore, these three late events were similarly repressed in an Al-tolerant cell line (ALT301) isolated from SL cells, suggesting that the acquisition of antioxidant functions mimicking butylated hydroxyanisol can be a mechanism of Al tolerance. In the pea root, Al also triggered ROS production, respiration inhibition, and ATP depletion, which were all correlated with inhibition of root elongation. Taken together, we conclude that Al affects mitochondrial functions, which leads to ROS production, probably the key critical event in Al inhibition of cell growth. PMID:11788753

Root architecture simulation improves the inference from seedling root phenotyping towards mature root systems.

PubMed

Zhao, Jiangsan; Bodner, Gernot; Rewald, Boris; Leitner, Daniel; Nagel, Kerstin A; Nakhforoosh, Alireza

2017-02-01

Root phenotyping provides trait information for plant breeding. A shortcoming of high-throughput root phenotyping is the limitation to seedling plants and failure to make inferences on mature root systems. We suggest root system architecture (RSA) models to predict mature root traits and overcome the inference problem. Sixteen pea genotypes were phenotyped in (i) seedling (Petri dishes) and (ii) mature (sand-filled columns) root phenotyping platforms. The RSA model RootBox was parameterized with seedling traits to simulate the fully developed root systems. Measured and modelled root length, first-order lateral number, and root distribution were compared to determine key traits for model-based prediction. No direct relationship in root traits (tap, lateral length, interbranch distance) was evident between phenotyping systems. RootBox significantly improved the inference over phenotyping platforms. Seedling plant tap and lateral root elongation rates and interbranch distance were sufficient model parameters to predict genotype ranking in total root length with an RSpearman of 0.83. Parameterization including uneven lateral spacing via a scaling function substantially improved the prediction of architectures underlying the differently sized root systems. We conclude that RSA models can solve the inference problem of seedling root phenotyping. RSA models should be included in the phenotyping pipeline to provide reliable information on mature root systems to breeding research. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Highly diverse microbiota in dental root canals in cases of apical periodontitis (data of illumina sequencing).

PubMed

Vengerfeldt, Veiko; Špilka, Katerina; Saag, Mare; Preem, Jens-Konrad; Oopkaup, Kristjan; Truu, Jaak; Mändar, Reet

2014-11-01

Chronic apical periodontitis (CAP) is a frequent condition that has a considerable effect on a patient's quality of life. We aimed to reveal root canal microbial communities in antibiotic-naive patients by applying Illumina sequencing (Illumina Inc, San Diego, CA). Samples were collected under strict aseptic conditions from 12 teeth (5 with primary CAP, 3 with secondary CAP, and 4 with a periapical abscess [PA]) and characterized by profiling the microbial community on the basis of the V6 hypervariable region of the 16S ribosomal RNA gene by using Illumina HiSeq2000 sequencing combinatorial sequence-tagged polymerase chain reaction products. Root canal specimens displayed highly polymicrobial communities in all 3 patient groups. One sample contained 5-8 (mean = 6.5) phyla of bacteria. The most numerous were Firmicutes and Bacteroidetes, but Actinobacteria, Fusobacteria, Proteobacteria, Spirochaetes, Tenericutes, and Synergistetes were also present in most of the patients. One sample contained 30-70 different operational taxonomic units; the mean (± standard deviation) was lower in the primary CAP group (36 ± 4) than in the PA (45 ± 4) and secondary CAP (43 ± 13) groups (P < .05). The communities were individually different, but anaerobic bacteria predominated as the rule. Enterococcus faecalis was found only in patients with secondary CAP. One PA sample displayed a significantly high proportion (47%) of Proteobacteria, mainly at the expense of Janthinobacterium lividum. This study provided an in-depth characterization of the microbiota of periapical tissues, revealing highly polymicrobial communities and minor differences between the study groups. A full understanding of the etiology of periodontal disease will only be possible through further in-depth systems-level analyses of the host-microbiome interaction. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Root Secreted Metabolites and Proteins Are Involved in the Early Events of Plant-Plant Recognition Prior to Competition

PubMed Central

Badri, Dayakar V.; De-la-Peña, Clelia; Lei, Zhentian; Manter, Daniel K.; Chaparro, Jacqueline M.; Guimarães, Rejane L.; Sumner, Lloyd W.; Vivanco, Jorge M.

2012-01-01

The mechanism whereby organisms interact and differentiate between others has been at the forefront of scientific inquiry, particularly in humans and certain animals. It is widely accepted that plants also interact, but the degree of this interaction has been constricted to competition for space, nutrients, water and light. Here, we analyzed the root secreted metabolites and proteins involved in early plant neighbor recognition by using Arabidopsis thaliana Col-0 ecotype (Col) as our focal plant co-cultured in vitro with different neighbors [A. thaliana Ler ecotype (Ler) or Capsella rubella (Cap)]. Principal component and cluster analyses revealed that both root secreted secondary metabolites and proteins clustered separately between the plants grown individually (Col-0, Ler and Cap grown alone) and the plants co-cultured with two homozygous individuals (Col-Col, Ler-Ler and Cap-Cap) or with different individuals (Col-Ler and Col-Cap). In particularly, we observed that a greater number of defense- and stress- related proteins were secreted when our control plant, Col, was grown alone as compared to when it was co-cultured with another homozygous individual (Col-Col) or with a different individual (Col-Ler and Col-Cap). However, the total amount of defense proteins in the exudates of the co-cultures was higher than in the plant alone. The opposite pattern of expression was identified for stress-related proteins. These data suggest that plants can sense and respond to the presence of different plant neighbors and that the level of relatedness is perceived upon initial interaction. Furthermore, the role of secondary metabolites and defense- and stress-related proteins widely involved in plant-microbe associations and abiotic responses warrants reassessment for plant-plant interactions. PMID:23056382

``Rhizogenesis in vitro'' - as a model to study microgravity biological effects

NASA Astrophysics Data System (ADS)

Bulavin, Iliya

Functioning organisms is based on the physiological and biochemical processes in different tissues and cells. Numerous spaceflight biological experiments have shown the essential changes in cell behavior of multicellular and unicellular organisms in comparison with that on Earth. In our investigations, we used the model “Rhizogenesis in vitro” to study cell differentiation in the root cap and growth zones under clinorotation. Advantage of this model is the possibility to study the influence of clinorotation at the beginning of root initiation de novo and next morphogenetic processes unlike experiments in vivo with embryonal seedling roots formed in seeds. Arabidopsis thaliana plants of wild type and scr mutant (3999 by NASC database) were used. For rhizogenesis induction, rosette leaves with petioles were cut and transferred in Petri dishes on MS medium contained 1/10 of MS mineral salt, without vitamins and hormones. One half of Petri dishes were placed vertically (control), the other - on a slow horizontal clinostat (2 rpm). Anatomical investigation of A. thaliana wild type and scr mutant roots formed de novo showed that formation of root cap and growth zones (meristem, distal elongation zone (DEZ), central elongation zone (CEZ) and mature zone) under clinorotation was similar to that in control. A root cap consists of columella and peripheral cells. In the columella there are meristematic cells, statocytes (graviperceptive cells), and secretory cells. Epidermis, parenchyma, endodermis and central cylinder are distinguished in wild type roots. Unlike a wild type, a cortex of scr mutant was represented by one cell layer which had the parenchyma and endodermis characteristics. A root cap length and width were similar in control and under clinorotation. A cell number in the meristem and DEZ and a length of these growth zones did not differ in control and the experimental conditions. The ultrasructure of cap meristematic cells was typical for cells of this type. Statocytes preserved their polarity in control but it was disturbed under clinorotation due to amyloplast distribution in the cytoplasm whole volume and/or their localization in the cell center. Structural rearrangements occurred similarly in statocytes under their transformation in secretory cells in control and under clinorotation. A characteristic features of the root proper meristematic cells in the control and in the experiment are central nucleus location, the great diversity of a size and a shape of mitochondria and plastids, poorly ER development, the presence of some small ER-bodies. As cells passed in the DEZ, their size enlarged but a nucleus can preserve the central location. A quantity of ER-cistern, vacuoles, and ER-bodies increased also. Dictyosomes acquired polarity and produced many Golgi vesicles. In CEZ cells, a large vacuole occupied the cell center, and the cytoplasm with organelles was on the cell periphery. So, we can conclude that under clinorotation: 1) the structure of a cap and growth zones of A. thaliana wild type and scr mutant roots formed de novo in vitro as similar to that in control; 2) a gaviperceptive apparatus formed in both objects but did not function. The obtained data allow to propose the model “Rhizogenesis in vitro” for using in spaceflight experiments to study the influence of real microgravity on the cellular differentiation and basic processes.

Effect of inhibitors of auxin transport and of calmodulin on a gravisensing-dependent current in maize roots

NASA Technical Reports Server (NTRS)

Bjorkman, T.; Leopold, A. C.

1987-01-01

Some characteristics of the gravity sensing mechanism in maize root caps were investigated using a bioelectric current as an indicator of gravity sensing. This technique involves the measurement of a change in the current density which arises at the columella region coincidently with the presentation time. Two inhibitors of auxin transport, triiodobenzoic acid and naphthylphthalamic acid, blocked gravitropic curvature but not the change in current density. Two inhibitors of calmodulin activity, compound 48/80 and calmidazolium, blocked both curvature and gravity-induced current. The results suggest that auxin transport is not a component of gravity sensing in the root cap. By contrast, the results suggest that calmodulin plays an intrinsic role in gravity sensing.

Root Apex Transition Zone As Oscillatory Zone

PubMed Central

Baluška, František; Mancuso, Stefano

2013-01-01

Root apex of higher plants shows very high sensitivity to environmental stimuli. The root cap acts as the most prominent plant sensory organ; sensing diverse physical parameters such as gravity, light, humidity, oxygen, and critical inorganic nutrients. However, the motoric responses to these stimuli are accomplished in the elongation region. This spatial discrepancy was solved when we have discovered and characterized the transition zone which is interpolated between the apical meristem and the subapical elongation zone. Cells of this zone are very active in the cytoskeletal rearrangements, endocytosis and endocytic vesicle recycling, as well as in electric activities. Here we discuss the oscillatory nature of the transition zone which, together with several other features of this zone, suggest that it acts as some kind of command center. In accordance with the early proposal of Charles and Francis Darwin, cells of this root zone receive sensory information from the root cap and instruct the motoric responses of cells in the elongation zone. PMID:24106493

Changes in extracellular calcium activity during gravity sensing in maize roots

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bjoerkman, T.; Cleland, R.E.

1990-05-01

A redistribution of calcium downward across the root cap has been proposed as an essential part of gravitropism in roots. Exogenous {sup 45}Ca moves preferentially downward across gravistimulated maize root tips. However, because of the many calcium-binding sites in the apoplast, this might not result in a physiologically effect change in the apoplasmic calcium activity. To test whether there is such a change, we measured the effect of gravistimulation on the calcium activity with calcium-specific microelectrodes. Decapped maize roots (Zea mays L. cv. Golden Cross Bantam) were grown for 31 h to regenerate gravitropic sensitivity, but not root caps. Themore » calcium activity in the apoplasm surrounding the gravity-sensing cells could then be measured. The initial pCa was 2.60 {plus minus} 0.28 (approx 2.5 mM). The calcium activity on the upper side of the root tip remained constant for about five minutes after gravistimulation, then decreased by about one half. On the lower side, after a similar lag the calcium activity doubled. Control roots, which were decapped but measured before recovering gravisensitivity (19 h), showed no change in calcium activity. We have found a distinct and rapid differential in the apoplasmic calcium activity between the upper and lower sides of gravistimulated maize root tips.« less

Cytoplasmic calcium levels in protoplasts from the cap and elongation zone of maize roots

NASA Technical Reports Server (NTRS)

Kiss, H. G.; Evans, M. L.; Johnson, J. D.

1991-01-01

Calcium has been implicated as a key component in the signal transduction process of root gravitropism. We measured cytoplasmic free calcium in protoplasts isolated from the elongation zone and cap of primary roots of light-grown, vertically oriented seedlings of Zea mays L. Protoplasts were loaded with the penta-potassium salts of fura-2 and indo-1 by incubation in acidic solutions of these calcium indicators. Loading increased with decreasing pH but the pH dependence was stronger for indo-1 than for fura-2. In the case of fura-2, loading was enhanced only at the lowest pH (4.5) tested. Dyes loaded in this manner were distributed predominantly in the cytoplasm as indicated by fluorescence patterns. As an alternative method of loading, protoplasts were incubated with the acetoxymethylesters of fura-2 and indo-1. Protoplasts loaded by this method exhibited fluorescence both in the cytoplasm and in association with various organelles. Cytoplasmic calcium levels measured using spectrofluorometry, were found to be 160 +/- 40 nM and 257 +/- 27 nM, respectively, in populations of protoplasts from the root cap and elongation zone. Cytoplasmic free calcium did not increase upon addition of calcium to the incubation medium, indicating that the passive permeability to calcium was low.

Root gravitropism: an experimental tool to investigate basic cellular and molecular processes underlying mechanosensing and signal transmission in plants

NASA Technical Reports Server (NTRS)

Boonsirichai, K.; Guan, C.; Chen, R.; Masson, P. H.

2002-01-01

The ability of plant organs to use gravity as a guide for growth, named gravitropism, has been recognized for over two centuries. This growth response to the environment contributes significantly to the upward growth of shoots and the downward growth of roots commonly observed throughout the plant kingdom. Root gravitropism has received a great deal of attention because there is a physical separation between the primary site for gravity sensing, located in the root cap, and the site of differential growth response, located in the elongation zones (EZs). Hence, this system allows identification and characterization of different phases of gravitropism, including gravity perception, signal transduction, signal transmission, and curvature response. Recent studies support some aspects of an old model for gravity sensing, which postulates that root-cap columellar amyloplasts constitute the susceptors for gravity perception. Such studies have also allowed the identification of several molecules that appear to function as second messengers in gravity signal transduction and of potential signal transducers. Auxin has been implicated as a probable component of the signal that carries the gravitropic information between the gravity-sensing cap and the gravity-responding EZs. This has allowed the identification and characterization of important molecular processes underlying auxin transport and response in plants. New molecular models can be elaborated to explain how the gravity signal transduction pathway might regulate the polarity of auxin transport in roots. Further studies are required to test these models, as well as to study the molecular mechanisms underlying a poorly characterized phase of gravitropism that is independent of an auxin gradient.

Complex physiological and molecular processes underlying root gravitropism

NASA Technical Reports Server (NTRS)

Chen, Rujin; Guan, Changhui; Boonsirichai, Kanokporn; Masson, Patrick H.

2002-01-01

Gravitropism allows plant organs to guide their growth in relation to the gravity vector. For most roots, this response to gravity allows downward growth into soil where water and nutrients are available for plant growth and development. The primary site for gravity sensing in roots includes the root cap and appears to involve the sedimentation of amyloplasts within the columella cells. This process triggers a signal transduction pathway that promotes both an acidification of the wall around the columella cells, an alkalinization of the columella cytoplasm, and the development of a lateral polarity across the root cap that allows for the establishment of a lateral auxin gradient. This gradient is then transmitted to the elongation zones where it triggers a differential cellular elongation on opposite flanks of the central elongation zone, responsible for part of the gravitropic curvature. Recent findings also suggest the involvement of a secondary site/mechanism of gravity sensing for gravitropism in roots, and the possibility that the early phases of graviresponse, which involve differential elongation on opposite flanks of the distal elongation zone, might be independent of this auxin gradient. This review discusses our current understanding of the molecular and physiological mechanisms underlying these various phases of the gravitropic response in roots.

Calcium movement, graviresponsiveness and the structure of columella cells and columella tissues in roots of Allium cepa L

NASA Technical Reports Server (NTRS)

Moore, R.

1985-01-01

Roots of Allium cepa L. cv. Yellow are differentially responsive to gravity. Long (e.g. 40 mm) roots are strongly graviresponsive, while short (c.g. 4 mm) roots are minimally responsive to gravity. Although columella cells of graviresponsive roots are larger than those of nongraviresponsive roots, they partition their volumes to cellular organelles similarly. The movement of amyloplasts and nuclei in columella cells of horizontally-oriented roots correlates positively with the onset of gravicurvature. Furthermore, there is no significant difference in the rates of organellar redistribution when graviresponsive and nongraviresponsive roots are oriented horizontally. The more pronounced graviresponsiveness of longer roots correlates positively with (1) their caps being 9-6 times more voluminous, (2) their columella tissues being 42 times more voluminous, (3) their caps having 15 times more columella cells, and (4) their columella tissues having relative volumes 4.4 times larger than those of shorter, nongraviresponsive roots. Graviresponsive roots that are oriented horizontally are characterized by a strongly polar movement of 45Ca2+ across the root tip from the upper to the lower side, while similarly oriented nongraviresponsive roots exhibit only a minimal polar transport of 45Ca2+. These results indicate that the differential graviresponsiveness of roots of A. cepa is probably not due to either (1) ultrastructural differences in their columella cells, (2) differences in the rates of organellar redistribution when roots are oriented horizontally. Rather, these results indicate the graviresponsiveness may require an extensive columella tissue, which, in turn, may be necessary for polar movement of 45Ca2+ across the root tip.

40 CFR 180.205 - Paraquat; tolerances for residues.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., roots 0.5 Beet, sugar, tops 0.05 Berry group 13 0.05 Biriba 0.05 Cacao bean, bean 0.05 Canistel 0.05... kidney 0.05 Cherimoya 0.05 Coffee, bean, green 0.05 Corn, field, forage 3.0 Corn, field, grain 0.1 Corn... Olive 0.05 Onion, bulb 0.1 Onion, green 0.05 Papaya 0.05 Passionfruit 0.2 Pawpaw 0.05 Pea and bean...

40 CFR 180.205 - Paraquat; tolerances for residues.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., roots 0.5 Beet, sugar, tops 0.05 Berry group 13 0.05 Biriba 0.05 Cacao bean, bean 0.05 Canistel 0.05... kidney 0.05 Cherimoya 0.05 Coffee, bean, green 0.05 Corn, field, forage 3.0 Corn, field, grain 0.1 Corn... Olive 0.05 Onion, bulb 0.1 Onion, green 0.05 Papaya 0.05 Passionfruit 0.2 Pawpaw 0.05 Pea and bean...

Constitutive arginine-dependent nitric oxide synthase activity in different organs of pea seedlings during plant development.

PubMed

Corpas, Francisco J; Barroso, Juan B; Carreras, Alfonso; Valderrama, Raquel; Palma, José M; León, Ana M; Sandalio, Luisa M; del Río, Luis A

2006-07-01

Nitric oxide (NO) is an important signalling molecule in different animal and plant physiological processes. Little is known about its biological function in plants and on the enzymatic source or site of NO production during plant development. The endogenous NO production from L-arginine (NO synthase activity) was analyzed in leaves, stems and roots during plant development, using pea seedlings as a model. NOS activity was analyzed using a novel chemiluminescence-based assay which is more sensitive and specific than previous methods used in plant tissues. In parallel, NO accumulation was analyzed by confocal laser scanning microscopy using as fluorescent probes either DAF-2 DA or DAF-FM DA. A strong increase in NOS activity was detected in stems after 11 days growth, coinciding with the maximum stem elongation. The arginine-dependent NOS activity was constitutive and sensitive to aminoguanidine, a well-known irreversible inhibitor of animal NOS, and this NOS activity was differentially modulated depending on the plant organ and seedling developmental stage. In all tissues studied, NO was localized mainly in the vascular tissue (xylem) and epidermal cells and in root hairs. These loci of NO generation and accumulation suggest novel functions for NO in these cell types.

Girdling and Applying Chemicals Promote Rapid Rooting of Sycamore Cuttings

Treesearch

Robert C. Hare

1975-01-01

Shoots of 6- and 13-year-old sycamore (Platanus occidentalis L.) were girdled and treated with rooting powder 4 weeks before cuttings were taken. The powder, which contained auxins, sucrose, and cap tan, was also applied basally to nongirdled cuttings immediately before iwertion in a rooting medium. Thirteen days later, 100 percent of the...

Cyclotron-based effects on plant gravitropism

NASA Astrophysics Data System (ADS)

Kordyum, E.; Sobol, M.; Kalinina, Ia.; Bogatina, N.; Kondrachuk, A.

Primary roots exhibit positive gravitropism and grow in the direction of the gravitational vector, while shoots respond negatively and grow opposite to the gravitational vector. We first demonstrated that the use of a weak combined magnetic field (CMF), which is comprised of a permanent magnetic field and an alternating magnetic field with the frequency resonance of the cyclotron frequency of calcium ions, can change root gravitropism from a positive direction to negative direction. Two-day-old cress seedlings were gravistimulated in a chamber that was placed into a μ-metal shield where this CMF was created. Using this "new model" of a root gravitropic response, we have studied some of its components including the movement of amyloplasts-statoliths in root cap statocytes and the distribution of Ca 2+ ions in the distal elongation zone during gravistimulation. Unlike results from the control, amyloplasts did not sediment in the distal part of a statocyte, and more Ca 2+ accumulation was observed in the upper side of a gravistimulated root for seedlings treated with the CMF. For plants treated with the CMF, it appears that a root gravitropic reaction occurs by a normal physiological process resulting in root bending although in the opposite direction. These results support the hypothesis that both the amyloplasts in the root cap statocytes and calcium are important signaling components in plant gravitropism.

Declination of copper toxicity in pigeon pea and soil system by growth-promoting Proteus vulgaris KNP3 strain.

PubMed

Rani, Anju; Shouche, Yogesh S; Goel, Reeta

2008-07-01

The copper-resistant (1318 microM CuSO(4).5H(2)O) strain KNP3 of Proteus vulgaris was isolated from soil near the Panki power plant, Kanpur, India, and was used to inoculate pigeon pea (Cajanus cajan var. UPS-120) seeds grown in soil for 60 days in the presence of 600 microM CuSO(4).5H(2)O. A study of siderophore production (126.34 +/- 0.52 microg ml(-1)) and its subsequent effects on plant growth promotion under in situ conditions was conducted. The parameters that were monitored included the plants' wet weight, dry weight, shoot length, chlorophyll content, and concentration of copper in plant roots and shoots. The results showed that the strain caused a significant (p < 0.05) increase in wet weight, dry weight, root length, shoot growth, and chlorophyll content (57.8%, 60%, 19.7%, 47.8%, and 36.3%, respectively) in the presence of copper. Furthermore, the strain reduced accumulation of Cu in the roots and shoots to 36.8% and 60.5%, respectively. Apart from this, copper concentration in the soil was measured on 0, 7, 15, 30, and 45 days consecutively and the results indicated that the bioinoculant KNP3 causes a significant decrease in Cu concentration in soil (55.6%), which was unlikely in the control (10.5%) treatment. The data suggested that the bacterial strain has the ability to protect plants against the inhibitory effects of copper besides reducing the copper load of the soil.

Branching in Pea (Action of Genes Rms3 and Rms4).

PubMed Central

Beveridge, C. A.; Ross, J. J.; Murfet, I. C.

1996-01-01

The nonallelic ramosus mutations rms3-2 and rms4 of pea (Pisum sativum L.) cause extensive release of vegetative axillary buds and lateral growth in comparison with wild-type (cv Torsdag) plants, in which axillary buds are not normally released under the conditions utilized. Grafting studies showed that the expression of the rms4 mutation in the shoot is independent of the genotype of the root-stock. In contrast, the length of the branches at certain nodes of rms3-2 plants was reduced by grafting to wild-type stocks, indicating that the wild-type Rms3 gene may control the level of a mobile substance produced in the root. This substance also appears to be produced in the shoot because Rms3 shoots did not branch when grafted to mutant rms3-2 rootstocks. However, the end product of the Rms3 gene appears to differ from that of the Rms2 gene (C.A. Beveridge, J.J. Ross, and I.C. Murfet [1994] Plant Physiol 104: 953-959) because reciprocal grafts between rms3-2 and rms2 seedlings produced mature shoots with apical dominance similar to that of rms3-2 and rms2 shoots grafted to wild-type stocks. Indole-3-acetic acid levels were not reduced in apical or nodal portions of rms4 plants and were actually elevated (up to 2-fold) in rms3-2 plants. It is suggested that further studies with these branching mutants may enable significant progress in understanding the normal control of apical dominance and the related communication between the root and shoot. PMID:12226224

Genetic Changes Accompanying the Domestication of Pisum sativum: Is there a Common Genetic Basis to the ‘Domestication Syndrome’ for Legumes?

PubMed Central

Weeden, Norman F.

2007-01-01

Background and Aims The changes that occur during the domestication of crops such as maize and common bean appear to be controlled by relatively few genes. This study investigates the genetic basis of domestication in pea (Pisum sativum) and compares the genes involved with those determined to be important in common bean domestication. Methods Quantitative trait loci and classical genetic analysis are used to investigate and identify the genes modified at three stages of the domestication process. Five recombinant inbred populations involving crosses between different lines representing different stages are examined. Key Results A minimum of 15 known genes, in addition to a relatively few major quantitative trait loci, are identified as being critical to the domestication process. These genes control traits such as pod dehiscence, seed dormancy, seed size and other seed quality characters, stem height, root mass, and harvest index. Several of the genes have pleiotropic effects that in species possessing a more rudimentary genetic characterization might have been interpreted as clusters of genes. Very little evidence for gene clustering was found in pea. When compared with common bean, pea has used a different set of genes to produce the same or similar phenotypic changes. Conclusions Similar to results for common bean, relatively few genes appear to have been modified during the domestication of pea. However, the genes involved are different, and there does not appear to be a common genetic basis to ‘domestication syndrome’ in the Fabaceae. PMID:17660515

Unique and Conserved Features of the Barley Root Meristem

PubMed Central

Kirschner, Gwendolyn K.; Stahl, Yvonne; Von Korff, Maria; Simon, Rüdiger

2017-01-01

Plant root growth is enabled by root meristems that harbor the stem cell niches as a source of progenitors for the different root tissues. Understanding the root development of diverse plant species is important to be able to control root growth in order to gain better performances of crop plants. In this study, we analyzed the root meristem of the fourth most abundant crop plant, barley (Hordeum vulgare). Cell division studies revealed that the barley stem cell niche comprises a Quiescent Center (QC) of around 30 cells with low mitotic activity. The surrounding stem cells contribute to root growth through the production of new cells that are displaced from the meristem, elongate and differentiate into specialized root tissues. The distal stem cells produce the root cap and lateral root cap cells, while cells lateral to the QC generate the epidermis, as it is typical for monocots. Endodermis and inner cortex are derived from one common initial lateral to the QC, while the outer cortex cell layers are derived from a distinct stem cell. In rice and Arabidopsis, meristem homeostasis is achieved through feedback signaling from differentiated cells involving peptides of the CLE family. Application of synthetic CLE40 orthologous peptide from barley promotes meristem cell differentiation, similar to rice and Arabidopsis. However, in contrast to Arabidopsis, the columella stem cells do not respond to the CLE40 peptide, indicating that distinct mechanisms control columella cell fate in monocot and dicot plants. PMID:28785269

Microsurgical removal of epidermal and cortical cells: evidence that the gravitropic signal moves through the outer cell layers in primary roots of maize

NASA Technical Reports Server (NTRS)

Yang, R. L.; Evans, M. L.; Moore, R.

1990-01-01

There is general agreement that during root gravitropism some sort of growth-modifying signal moves from the cap to the elongation zone and that this signal ultimately induces the curvature that leads to reorientation of the root. However, there is disagreement regarding both the nature of the signal and the pathway of its movement from the root cap to the elongation zone. We examined the pathway of movement by testing gravitropism in primary roots of maize (Zea mays L.) from which narrow (0.5 mm) rings of epidermal and cortical tissue were surgically removed from various positions within the elongation zone. When roots were girdled in the apical part of the elongation zone gravitropic curvature occurred apical to the girdle but not basal to the girdle. Filling the girdle with agar allowed curvature basal to the girdle to occur. Shallow girdles, in which only two or three cell layers (epidermis plus one or two cortical cell layers) were removed, prevented or greatly delayed gravitropic curvature basal to the girdle. The results indicate that the gravitropic signal moves basipetally through the outermost cell layers, perhaps through the epidermis itself.

Impact of pigeon pea biochar on cadmium mobility in soil and transfer rate to leafy vegetable spinach.

PubMed

Coumar, M Vassanda; Parihar, R S; Dwivedi, A K; Saha, J K; Rajendiran, S; Dotaniya, M L; Kundu, S

2016-01-01

Introduction of heavy metals in the environment by various anthropogenic activities has become a potential treat to life. Among the heavy metals, cadmium (Cd) shows relatively high soil mobility and has high phyto-mammalian toxicity. Integration of soil remediation and ecosystem services, such as carbon sequestration in soils through organic amendments, may provide an attractive land management option for contaminated sites. The application of biochar in agriculture has recently received much attention globally due to its associated multiple benefits, particularly, long-term carbon storage in soil. However, the application of biochar from softwood crop residue for heavy metal immobilization, as an alternative to direct field application, has not received much attention. Hence, a pot experiment was conducted to study the effect of pigeon pea biochar on cadmium mobility in a soil-plant system in cadmium-spiked sandy loam soil. The biochar was prepared from pigeon pea stalk through a slow pyrolysis method at 300 °C. The experiment was designed with three levels of Cd (0, 5, and 10 mg Cd kg(-1) soil) and three levels of biochar (0, 2.5, and 5 g kg(-1) soil) using spinach as a test crop. The results indicate that with increasing levels of applied cadmium at 5 and 10 mg kg(-1) soil, the dry matter yield (DMY) of spinach leaf decreased by 9.84 and 18.29 %, respectively. However, application of biochar (at 2.5 and 5 g kg(-1) soil) significantly increased the dry matter yield of spinach leaf by 5.07 and 15.02 %, respectively, and root by 14.0 and 24.0 %, respectively, over the control. Organic carbon content in the post-harvest soil increased to 34.9 and 60.5 % due to the application of biochar 2.5 and 5 g kg(-1) soil, respectively. Further, there was a reduction in the diethylene triamine pentaacetic acid (DTPA)-extractable cadmium in the soil and in transfer coefficient values (soil to plant), as well as its concentrations in spinach leaf and root, indicating that cadmium mobility was decreased due to biochar application. This study shows that pigeon pea biochar has the potential to increase spinach yield and reduce cadmium mobility in contaminated sandy soil.

Border cell release: Cell separation without cell wall degradation?

PubMed

Mravec, Jozef

2017-07-03

Plant border cells are specialized cells derived from the root cap with roles in the biomechanics of root growth and in forming a barrier against pathogens. The mechanism of highly localized cell separation which is essential for their release to the environment is little understood. Here I present in situ analysis of Brachypodium distachyon, a model organism for grasses which possess type II primary cell walls poor in pectin content. Results suggest similarity in spatial dynamics of pectic homogalacturonan during dicot and monocot border cell release. Integration of observations from different species leads to the hypothesis that this process most likely does not involve degradation of cell wall material but rather uses unique cell wall structural and compositional means enabling both the rigidity of the root cap as well as detachability of given cells on its surface.

The model of root graviresponse with retarded arguments

NASA Astrophysics Data System (ADS)

Kondrachuk, Alexander

The graviperception mechanism (GPM) of the roots of higher plants localized in the cap region of a root and supposedly related to statoliths sedimentation produces the signals in response to the change of the root axis orientation relative to the gravity vector G. Meanwhile, the regions (Distal Elongation Zone -DEZ and Central Elongation Zone-CEZ), where the signals initiate the changes of the growth rates of the upper and lower flanks of the root, are located at the significant distances from the cap (thousands microns for some plants). It causes the time delays between the relocation of statoliths in statocytes and the change of the growth rates in elongation zones. It is suggested that the signal targeting the CEZ modulates the initially uniform lateral distribution of some specific substances (S) in the cap region. Then already nonhomogeneous lateral distribution of S is transferred to the CEZ to initiate the change of the growth rates of the opposite flanks. It results in the bending of the root in the line of G and thus in the change of the GPM signal in the cap region. In the present model the kinetics of a root apex bending (angle A) in response to the time (t)-dependent change of the G orientation is described by the integro-differential equation in A(t). The main peculiarity of this model is the presence of retarded (time-delayed) arguments t-TCEZ and t-TDEZ . In this case the solutions of this equation depend on the preceding kinetics of A(t) during the time delays TCEZ and TDEZ . It is suggested that the signals activating the CEZ and DEZ are of different nature. The work is focused on two problems concerning the modeling of the effects of time-delay(s) on the root bending. The first problem supposes the existence of one zone (CEZ) and one time-delay TCEZ . This equation was studied and solved using analytical and numerical methods. We analyzed the model as to whether it can be used to describe the kinetics of root graviresponse in the case of different orientations of the root apex relative to the G vector during the time interval equal to TCEZ (TCEZ > TDEZ ) that precedes the beginning of gravistimultion. Also we explored the conditions of the overshooting (the vertical) and non-overshooting regimes of gravistimulated root bending. Good correlation between the results of the modeling and known experimental data (Barlow et al, 1993, Stochkus, 1994, Mullen, 1998) was found. This allowed us to estimate and analyze the parameters of the model. The second problem supposed the existence of two zones of growth (CEZ and DEZ) and two corresponding time-delays. The effects of the second time-delay connected with the presence of the DEZ on the behavior of the model equation of the root graviresponse kinetics were analyzed and discussed.

The role of calcium in the desensitization of capsaicin responses in rat dorsal root ganglion neurons.

PubMed

Koplas, P A; Rosenberg, R L; Oxford, G S

1997-05-15

Capsaicin (Cap) is a pungent extract of the Capsicum pepper family, which activates nociceptive primary sensory neurons. Inward current and membrane potential responses of cultured neonatal rat dorsal root ganglion neurons to capsaicin were examined using whole-cell and perforated patch recording methods. The responses exhibited strong desensitization operationally classified as acute (diminished response during constant Cap exposure) and tachyphylaxis (diminished response to successive applications of Cap). Both acute desensitization and tachyphylaxis were greatly diminished by reductions in external Ca2+ concentration. Furthermore, chelation of intracellular Ca2+ by addition of either EGTA or bis(2-aminophenoxy)ethane-N,N,N',N'-tetra-acetic acid to the patch pipette attenuated both forms of desensitization even in normal Ca2+. Release of intracellular Ca2+ by caffeine triggered acute desensitization in the absence of extracellular Ca2+, and barium was found to effectively substitute for calcium in supporting desensitization. Cap activated inward current at an ED50 of 728 nM, exhibiting cooperativity (Hill coefficient, 2.2); however, both forms of desensitization were only weakly dependent on [Cap], suggesting a dissociation between activation of Cap-sensitive channels and desensitization. Removal of ATP and GTP from the intracellular solutions resulted in nearly complete tachyphylaxis even with intracellular Ca2+ buffered to low levels, whereas changes in nucleotide levels did not significantly alter the acute form of desensitization. These data suggest a key role for intracellular Ca2+ in desensitization of Cap responses, perhaps through Ca2+-dependent dephosphorylation at a locus that normally sustains Cap responsiveness via ATP-dependent phosphorylation. It also seems that the signaling mechanisms underlying the two forms of desensitization are not identical in detail.

The Ca2+ pump inhibitor, thapsigargin, inhibits root gravitropism in Arabidopsis thaliana.

PubMed

Urbina, Daniela C; Silva, Herman; Meisel, Lee A

2006-01-01

Thapsigargin, a specific inhibitor of most animal intracellular SERCA-type Ca2+ pumps present in the sarcoplasmic/endoplasmic reticulum, was originally isolated from the roots of the Mediterranean plant Thapsia gargancia L. Here, we demonstrate that this root-derived compound is capable of altering root gravitropism in Arabidopsis thaliana. Thapsigargin concentrations as low as 0.1 microM alter root gravitropism whereas under similar conditions cyclopiazonic acid does not. Furthermore, a fluorescently conjugated thapsigargin (BODIPY FL thapsigargin) suggests that target sites for thapsigargin are located in intracellular organelles in the root distal elongation zone and the root cap, regions known to regulate root gravitropism.

Distribution of calmodulin in corn seedlings - Immunocytochemical localization in coleoptiles and root apices

NASA Technical Reports Server (NTRS)

Dauwalder, M.; Roux, S. J.

1986-01-01

Immunofluorescence techniques have been used to study the distribution of calmodulin in several tissues in etiolated corn (Zea mays, var. Bear Hybrid) seedlings. Uniform staining was seen in the background cytoplasm of most cell types. Cell walls and vacuoles were not stained. In coleoptile mesophyll cells the nucleoplasm of most nuclei was stained as was the stroma of most amyloplasts. The lumen border of mature tracheary elements in coleoptiles also stained. In the rootcap the most intensely stained regions were the cytoplasms of columella cells and of the outermost cells enmeshed in the layer of secreted slime. Nuclei in the rootcap cells did not stain distinctly, but those in all cell types of the root meristem did. Also in the root meristem, the cytoplasm of metaxylem elements stained brightly. These results are compared and contrasted with previous data on the localization of calmodulin in pea root apices and epicotyls and discussed in relation to current hypotheses on mechanisms of gravitropism.

Members of the aquaporin family in the developing pea seed coat include representatives of the PIP, TIP, and NIP subfamilies.

PubMed

Schuurmans, Jolanda A M J; van Dongen, Joost T; Rutjens, Bas P W; Boonman, Alex; Pieterse, Corné M J; Borstlap, Adrianus C

2003-11-01

Water and nutrients required by developing seeds are mainly supplied by the phloem and have to be released from a maternal parenchyma tissue before being utilized by the filial tissues of embryo and endosperm. To identify aquaporins that could be involved in this process four full-length cDNAs were cloned and sequenced from a cDNA library of developing seed coats of pea (Pisum sativum L.). The cDNA of PsPIP1-1 appeared to be identical to that of clone 7a/TRG-31, a turgor-responsive gene cloned previously from pea roots. PsPIP1-1, PsPIP2-1, and PsTIP1-1, or their possible close homologues, were also expressed in cotyledons of developing and germinating seeds, and in roots and shoots of seedlings, but transcripts of PsNIP-1 were only detected in the seed coat. In mature dry seeds, high hybridization signals were observed with the probe for PsPIP1-1, but transcripts of PsPIP2-1, PsTIP1-1, and PsNIP-1 were not detected. Functional characterization after heterologous expression in Xenopus oocytes showed that PsPIP2-1 and PsTIP1-1 are aquaporins whereas PsNIP-1 is an aquaglyceroporin. PsNIP-1, like several other NIPs, contains a tryptophan residue corresponding with Trp-48 in GlpF (the glycerol facilitator of Escherichia coli) that borders the selectivity filter in the permeation channel. It is suggested that PsPIP1-1 and/or its possible close homologues could play a role in water absorption during seed imbibition, and that PsPIP2-1, possibly together with PsPIP1-1, could be involved in the release of phloem water from the seed coat symplast, which is intimately connected with the release of nutrients for the embryo.

Root cytoskeleton: its role in perception of and response to gravity

NASA Technical Reports Server (NTRS)

Baluska, F.; Hasenstein, K. H.

1997-01-01

We have critically evaluated the possible functions of the plant cytoskeleton in root gravisensing and graviresponse and discussed the evidence that microtubules (MTs) and actin microfilaments (MFs) do not control differential cell growth during bending of roots. On the other hand, MF and MT networks are envisaged to participate in gravisensing because of the mechanical properties of the cytoskeletal structures that interconnect plant cell organelles with the plasma membrane. In restrained gravisensing, forces are suggested to be transmitted to membranes because large-scale gravity-dependent repositioning of organelles is effectively prevented due to the cytoskeleton-mediated anchorage of their envelopes at the plasma membrane. From the cytoskeletal point of view, we can also envisage an unrestrained gravity sensing when cytoskeletal tethers are not strong enough to preserve the tight control over distribution of organelles and the latter, if heavy enough, are allowed to sediment towards the physical bottom of cells. This situation obviously occurs in root cap statocytes because these uniquely organized cells are depleted of prominent actin MF bundles, endoplasmic MT arrays, and ER elements in their internal cytoplasm. Nevertheless, indirect evidence clearly indicates that sedimented root cap statoliths are enmeshed within fine but dynamic MF networks and that their behaviour is obviously under, at least partial, cytoskeletal control. The actomyosin-enriched domain among and around amyloplasts is proposed to increase the perception of gravity due to the grouping effect of sedimenting statoliths. Cytoskeletal links between myosin-rich statoliths, and cell peripheries well equipped with dense cortical MTs, membrane-associated cytoskeleton, as well as with ER elements, would allow efficient restrained gravisensing only at the statocyte cell cortex. As a consequence of cytoskeletal depletion in the internal statocyte cytoplasm and bulk sedimentation of large amyloplasts, restrained gravisensing is spatially restricted to the bottom of the statocyte irrespective of whether roots are vertical or horizontal. This spatial aspect allows for efficient gravisensing via amplification of gravity-induced impacts on the cellular architecture, a phenomenon which is unique to root cap statocytes.

Phytotoxicity of sulfamethazine soil pollutant to six legume plant species.

PubMed

Piotrowicz-Cieślak, Agnieszka I; Adomas, Barbara; Nałecz-Jawecki, Grzegorz; Michalczyk, Dariusz J

2010-01-01

The effect of traces of sulfamethazine (SMZ) in soil (0.01, 0.1, 0.25, 1, 5, 15, and 20 mM) on cellular distribution of cytochrome c oxidase activity, shoot and root growth, and leachate electroconductivity was analyzed in germinating seeds of yellow lupin, pea, lentil, soybean, adzuki bean, and alfalfa. Results showed that a high activity of cytochrome c oxidase in mitochondria correlated with high seed vigor and viability. The appearance of necroses and root decay was associated with a decrease in the activity of mitochondrial cytochrome c oxidase but was accompanied by an increase in cytosolic cytochrome c oxidase activity. A short exposure period of seeds (3 and 6 d) to sulfamethazine did not influence germination. Elongation of roots and stems was more sensitive than germination rate as an indicator of soil contamination by sulfamethazine. Among all tested leguminous plants, yellow lupin was the most reliable bioindicator of SMZ contaminated soil.

Mineral Ion Contents and Cell Transmembrane Electropotentials of Pea and Oat Seedling Tissue 1

PubMed Central

Higinbotham, N.; Etherton, Bud; Foster, R. J.

1967-01-01

The relationships of concentration gradients to electropotential gradients resulting from passive diffusion processes, after equilibration, are described by the Nernst equation. The primary criterion for the hypothesis that any given ion is actively transported is to establish that it is not diffusing passively. A test was made of how closely the Nernst equation describes the electrochemical equilibrium in seedling tissues. Segments of roots and epicotyl internodes of pea (Pisum sativum var. Alaska) and of roots and coleoptiles of oat (Avena sativa var. Victory) seedlings were immersed and shaken in defined nutrient solutions containing eight major nutrients (K+, Na+, Ca2+, Mg2+, Cl−, NO3−, H2PO4− and SO42−) at 1-fold and 10-fold concentrations. The tissue content of each ion was assayed at 0, 8, 24, and 48 hours. A near-equilibrium condition was approached by roots for most ions; however, the segments of shoot tissue generally continued to show a net accumulation of some ions, mainly K+ and NO3−. Only K+ approached a reasonable fit to the Nernst equation and this was true for the 1-fold concentration but not the 10-fold. The data suggest that for Na+, Mg2+, and Ca2+ the electrochemical gradient is from the external solution to the cell interior; thus passive diffusion should be in an inward direction. Consequently, some mechanism must exist in plant tissue either to exclude these cations or to extrude them (e.g., by an active efflux pump). For each of the anions the electrochemical gradient is from the tissue to the solution; thus an active influx pump for anions seems required. Root segments approach ionic equilibrium with the solution concentration in which the seedlings were grown. Segments of shoot tissue, however, are far removed from such equilibration. Thus in the intact seedling the extracellular (wall space) fluid must be very different from that of the nutrient solution bathing the segments; it would appear that the root is the site of regulation of ion uptake in the intact plant although other correlative mechanisms may be involved. PMID:16656483

Alteration of plasma membrane-bound redox systems of iron deficient pea roots by chitosan.

PubMed

Meisrimler, Claudia-Nicole; Planchon, Sebastien; Renaut, Jenny; Sergeant, Kjell; Lüthje, Sabine

2011-08-12

Iron is essential for all living organisms and plays a crucial role in pathogenicity. This study presents the first proteome analysis of plasma membranes isolated from pea roots. Protein profiles of four different samples (+Fe, +Fe/Chitosan, -Fe, and -Fe/Chitosan) were compared by native IEF-PAGE combined with in-gel activity stains and DIGE. Using DIGE, 89 proteins of interest were detected in plasma membrane fractions. Data revealed a differential abundance of several spots in all samples investigated. In comparison to the control and -FeCh the abundance of six protein spots increased whereas 56 spots decreased in +FeCh. Altered protein spots were analyzed by MALDI-TOF-TOF mass spectrometry. Besides stress-related proteins, transport proteins and redox enzymes were identified. Activity stains after native PAGE and spectrophotometric measurements demonstrated induction of a ferric-chelate reductase (-Fe) and a putative respiratory burst oxidase homolog (-FeCh). However, the activity of the ferric-chelate reductase decreased in -Fe plants after elicitor treatment. The activity of plasma membrane-bound class III peroxidases increased after elicitor treatment and decreased under iron-deficiency, whereas activity of quinone reductases decreased mostly after elicitor treatment. Possible functions of proteins identified and reasons for a weakened pathogen response of iron-deficient plants were discussed. Copyright © 2011 Elsevier B.V. All rights reserved.

The pharmaceutical vial capping process: Container closure systems, capping equipment, regulatory framework, and seal quality tests.

PubMed

Mathaes, Roman; Mahler, Hanns-Christian; Buettiker, Jean-Pierre; Roehl, Holger; Lam, Philippe; Brown, Helen; Luemkemann, Joerg; Adler, Michael; Huwyler, Joerg; Streubel, Alexander; Mohl, Silke

2016-02-01

Parenteral drug products are protected by appropriate primary packaging to protect against environmental factors, including potential microbial contamination during shelf life duration. The most commonly used CCS configuration for parenteral drug products is the glass vial, sealed with a rubber stopper and an aluminum crimp cap. In combination with an adequately designed and controlled aseptic fill/finish processes, a well-designed and characterized capping process is indispensable to ensure product quality and integrity and to minimize rejections during the manufacturing process. In this review, the health authority requirements and expectations related to container closure system quality and container closure integrity are summarized. The pharmaceutical vial, the rubber stopper, and the crimp cap are described. Different capping techniques are critically compared: The most common capping equipment with a rotating capping plate produces the lowest amount of particle. The strength and challenges of methods to control the capping process are discussed. The residual seal force method can characterize the capping process independent of the used capping equipment or CCS. We analyze the root causes of several cosmetic defects associated with the vial capping process. Copyright © 2015 Elsevier B.V. All rights reserved.

The pea branching RMS2 gene encodes the PsAFB4/5 auxin receptor and is involved in an auxin-strigolactone regulation loop

PubMed Central

Ligerot, Yasmine; de Saint Germain, Alexandre; Troadec, Christelle; Citerne, Sylvie; Pillot, Jean-Paul; Prigge, Michael; Aubert, Grégoire; Bendahmane, Abdelhafid; Estelle, Mark; Debellé, Frédéric

2017-01-01

Strigolactones (SLs) are well known for their role in repressing shoot branching. In pea, increased transcript levels of SL biosynthesis genes are observed in stems of highly branched SL deficient (ramosus1 (rms1) and rms5) and SL response (rms3 and rms4) mutants indicative of negative feedback control. In contrast, the highly branched rms2 mutant has reduced transcript levels of SL biosynthesis genes. Grafting studies and hormone quantification led to a model where RMS2 mediates a shoot-to-root feedback signal that regulates both SL biosynthesis gene transcript levels and xylem sap levels of cytokinin exported from roots. Here we cloned RMS2 using synteny with Medicago truncatula and demonstrated that it encodes a putative auxin receptor of the AFB4/5 clade. Phenotypes similar to rms2 were found in Arabidopsis afb4/5 mutants, including increased shoot branching, low expression of SL biosynthesis genes and high auxin levels in stems. Moreover, afb4/5 and rms2 display a specific resistance to the herbicide picloram. Yeast-two-hybrid experiments supported the hypothesis that the RMS2 protein functions as an auxin receptor. SL root feeding using hydroponics repressed auxin levels in stems and down-regulated transcript levels of auxin biosynthesis genes within one hour. This auxin down-regulation was also observed in plants treated with the polar auxin transport inhibitor NPA. Together these data suggest a homeostatic feedback loop in which auxin up-regulates SL synthesis in an RMS2-dependent manner and SL down-regulates auxin synthesis in an RMS3 and RMS4-dependent manner. PMID:29220348

The pea branching RMS2 gene encodes the PsAFB4/5 auxin receptor and is involved in an auxin-strigolactone regulation loop.

PubMed

Ligerot, Yasmine; de Saint Germain, Alexandre; Waldie, Tanya; Troadec, Christelle; Citerne, Sylvie; Kadakia, Nikita; Pillot, Jean-Paul; Prigge, Michael; Aubert, Grégoire; Bendahmane, Abdelhafid; Leyser, Ottoline; Estelle, Mark; Debellé, Frédéric; Rameau, Catherine

2017-12-01

Strigolactones (SLs) are well known for their role in repressing shoot branching. In pea, increased transcript levels of SL biosynthesis genes are observed in stems of highly branched SL deficient (ramosus1 (rms1) and rms5) and SL response (rms3 and rms4) mutants indicative of negative feedback control. In contrast, the highly branched rms2 mutant has reduced transcript levels of SL biosynthesis genes. Grafting studies and hormone quantification led to a model where RMS2 mediates a shoot-to-root feedback signal that regulates both SL biosynthesis gene transcript levels and xylem sap levels of cytokinin exported from roots. Here we cloned RMS2 using synteny with Medicago truncatula and demonstrated that it encodes a putative auxin receptor of the AFB4/5 clade. Phenotypes similar to rms2 were found in Arabidopsis afb4/5 mutants, including increased shoot branching, low expression of SL biosynthesis genes and high auxin levels in stems. Moreover, afb4/5 and rms2 display a specific resistance to the herbicide picloram. Yeast-two-hybrid experiments supported the hypothesis that the RMS2 protein functions as an auxin receptor. SL root feeding using hydroponics repressed auxin levels in stems and down-regulated transcript levels of auxin biosynthesis genes within one hour. This auxin down-regulation was also observed in plants treated with the polar auxin transport inhibitor NPA. Together these data suggest a homeostatic feedback loop in which auxin up-regulates SL synthesis in an RMS2-dependent manner and SL down-regulates auxin synthesis in an RMS3 and RMS4-dependent manner.

Localization in roots and flowers of pea chloroplastic thioredoxin f and thioredoxin m proteins reveals new roles in nonphotosynthetic organs.

PubMed

de Dios Barajas-López, Juan; Serrato, Antonio Jesús; Olmedilla, Adela; Chueca, Ana; Sahrawy, Mariam

2007-11-01

Plant thioredoxins (TRXs) are involved in redox regulation of a wide variety processes and usually exhibit organ specificity. We report strong evidence that chloroplastic TRXs are localized in heterotrophic tissues and suggest some ways in which they might participate in several metabolic and developmental processes. The promoter regions of the chloroplastic f and m1 TRX genes were isolated from a pea (Pisum sativum) plant genomic bank. Histochemical staining for beta-glucuronidase (GUS) in transgenic homozygous Arabidopsis (Arabidopsis thaliana) plants showed preferential expression of the 444-bp PsTRXf1 promoter in early seedlings, stems, leaves, and roots, as well as in flowers, stigma, pollen grains, and filaments. GUS activity under the control of the 1,874-bp PsTRXm1 promoter was restricted to the leaves, roots, seeds, and flowers. To gain insight into the translational regulation of these genes, a series of deletions of 5' elements in both TRX promoters were analyzed. The results revealed that a 126-bp construct of the PsTRXf2 promoter was unable to reproduce the expression pattern observed with the full promoter. The differences in expression and tissue specificity between PsTRXm1 and the deleted promoters PsTRXm2 and PsTRXm3 suggest the existence of upstream positive or negative regulatory regions that affect tissue specificity, sucrose metabolism, and light regulation. PsTRXm1 expression is finely regulated by light and possibly by other metabolic factors. In situ hybridization experiments confirmed new localizations of these chloroplastic TRX transcripts in vascular tissues and flowers, and therefore suggest possible new functions in heterotrophic tissues related to cell division, germination, and plant reproduction.

[Environmental Effect of Substrate Amelioration on Lake: Effects on Phragmites communis Growth and Photosynthetic Fluorescence Characteristics].

PubMed

Yu, Ju-hua; Zhong, Ji-cheng; Fan, Cheng-xin; Huang, Wei; Shang, Jing-ge; Gu, Xiao-zhi

2015-12-01

Growth of rooted aquatic macrophytes was affected by the nature and composition of lake bottom sediments. Obviously, it has been recognized as an important ecological restoration measure by improving lake substrate and then reestablishing and restoring aquatic macrophytes in order to get rid of the environmental problem of lake. This study simulated five covering thickness to give an insight into the influence of substrate amelioration on Phragmites communis growth and photosynthetic fluorescence characteristics. The results showed that the total biomass, plant height, leaf length and leaf width of Phragmites communis under capping 5 cm were much more significant than those of capping 18 cm (P < 0.01), at the 120 d, the underground: shoot biomass ratio and fine root: underground biomass ratio were also much higher than those of other treatments (P < 0.05), which indicated that capping 18 cm treatment would significantly inhibit the growth of Phragmites communis , but the growth of control group Phragmites communis was slightly constrained by eutrophicated sediment. In addition, as the capping thickness growing, the underground: shoot biomass ratio of the plant would be reduced dramatically, in order to acquire much more nutrients from sediment for plant growing, the underground biomass of Phragmites communis would be preferentially developed, especially, the biomass of fine root. However, Photosystem II (PS II) photochemical efficiency (Fv/Fm), quantum yield (Yield), photochemical quenching (qP), non-photochemical quenching (qN) of Phragmites communis under different treatments had no significant differences (P > 0.05), furthermore, with much greater capping thickness, the photosynthesis structure of PS II would be much easier destroyed, and PS II would be protected by increasing heat dissipating and reducing leaf photosynthetic area and leaf light-captured pigment contents. In terms of the influence of sediment amelioration by soil exchange on the growth and photosynthetic fluorescence characteristics of Phragmites communis, plant growth could be effectively promoted under capping 2 cm and capping 5 cm by increasing the Eh value and nutrient content, whereas plant under capping 18 cm would be much easier adaptive to low-light stress in winter season, of which capping 2 cm treatment was conducive to enhance the initial slope of RLCs (α), maximum electron transport rate (ETRmax) and minimum saturating irradiance (Ek). With regard to the harness of environmental problem of lake, the eutrophication status of lake will be mitigated by using multi-ecological measures to control the internal nutrients content once the external loading was first effectively controlled.

Understanding pea resistance mechanisms in response to Fusarium oxysporum through proteomic analysis.

PubMed

Castillejo, María Ángeles; Bani, Moustafa; Rubiales, Diego

2015-07-01

Fusarium oxysporum f. sp. pisi (Fop) is an important and destructive pathogen affecting pea crop (Pisum sativum) throughout the world. Control of this disease is achieved mainly by integration of different disease management procedures. However, the constant evolution of the pathogen drives the necessity to broaden the molecular basis of resistance to Fop. Our proteomic study was performed on pea with the aim of identifying proteins involved in different resistance mechanisms operating during F. oxysporum infection. For such purpose, we used a two-dimensional electrophoresis (2-DE) coupled to mass spectrometry (MALDI-TOF/TOF) analysis to study the root proteome of three pea genotypes showing different resistance response to Fop race 2. Multivariate statistical analysis identified 132 differential protein spots under the experimental conditions (genotypes/treatments). All of these protein spots were subjected to mass spectrometry analysis to deduce their possible functions. A total of 53 proteins were identified using a combination of peptide mass fingerprinting (PMF) and MSMS fragmentation. The following main functional categories were assigned to the identified proteins: carbohydrate and energy metabolism, nucleotides and aminoacid metabolism, signal transduction and cellular process, folding and degradation, redox and homeostasis, defense, biosynthetic process and transcription/translation. Results obtained in this work suggest that the most susceptible genotypes have increased levels of enzymes involved in the production of reducing power which could then be used as cofactor for enzymes of the redox reactions. This is in concordance with the fact that a ROS burst occurred in the same genotypes, as well as an increase of PR proteins. Conversely, in the resistant genotype proteins responsible to induce changes in the membrane and cell wall composition related to reinforcement were identified. Results are discussed in terms of the differential response to Fop. Copyright © 2015 Elsevier Ltd. All rights reserved.

An electric current associated with gravity sensing in maize roots

NASA Technical Reports Server (NTRS)

Bjorkman, T.; Leopold, A. C.

1987-01-01

The study of gravisensing would be greatly enhanced if physiological events associated with gravity sensing could be detected separately from subsequent growth processes. This report presents a means to discriminate sensing from the growth processes. By using a vibrating probe, we have found an electric current generated by the gravity sensing region of the root cap of maize (Zea mays cv Merit) in response to gravistimulation. On the upper surface of the root cap, the change from the endogenous current has a density of 0.55 microampere per square centimeter away from gravity. The onset of the current shift has a characteristic of lag of three to four minutes after gravistimulation, which corresponds to the presentation time for gravity sensing in this tissue. A description of the current provides some information about the sensing mechanism, as well as being a valuable means to detect gravity sensing independently of differential growth.

Poly(ester amine) Composed of Polyethylenimine and Pluronic Enhance Delivery of Antisense Oligonucleotides In Vitro and in Dystrophic mdx Mice

PubMed Central

Wang, Mingxing; Wu, Bo; Tucker, Jason D; Bollinger, Lauren E; Lu, Peijuan; Lu, Qilong

2016-01-01

A series of poly(esteramine)s (PEAs) constructed from low molecular weight polyethyleneimine (LPEI) and Pluronic were evaluated for the delivery of antisense oligonuclotides (AOs), 2′-O-methyl phosphorothioate RNA (2′-OMePS) and phosphorodiamidate morpholino oligomer (PMO) in cell culture and dystrophic mdx mice. Improved exon-skipping efficiency of both 2′-OMePS and PMO was observed in the C2C12E50 cell line with all PEA polymers compared with PEI 25k or LF-2k. The degree of efficiency was found in the order of PEA 01, PEA 04 > PEA 05 > others. The in vivo study in mdx mice demonstrated enhanced exon-skipping of 2′-OMePS with the order of PEA 06 > PEA 04, PEA 07 > PEA 03 > PEA 01 > others, and much higher than PEI 25k formulated 2′-OMePS. Exon-skipping efficiency of PMO in formulation with the PEAs were significantly enhanced in the order of PEA 02 > PEA 10 > PEA 01, PEA 03 > PEA 05, PEA 07, PEA 08 > others, with PEA 02 reaching fourfold of Endo-porter formulated PMO. PEAs improve PMO delivery more effectively than 2′-OMePS delivery in vivo, and the systemic delivery evaluation further highlight the efficiency of PEA for PMO delivery in all skeletal muscle. The results suggest that the flexibility of PEA polymers could be explored for delivery of different AO chemistries, especially for antisense therapy. PMID:27483024

Gravity-induced changes in intracellular potentials in elongating cortical cells of mung bean roots

NASA Technical Reports Server (NTRS)

Ishikawa, H.; Evans, M. L.

1990-01-01

Gravity-induced changes in intracellular potentials in primary roots of 2-day-old mung bean (Vigna mungo L. cv. black matpe) seedlings were investigated using glass microelectrodes held by 3-dimensional hydraulic micro-drives. The electrodes were inserted into outer cortical cells within the elongation zone. Intracellular potentials, angle of root orientation with respect to gravity, and position within the root of the impaled cortical cell were measured simultaneously. Gravistimulation caused intracellular potential changes in cortical cells of the elongation zone. When the roots were oriented vertically, the intracellular potentials of the outer cortical cells (2 mm behind the root apex) were approximately - 115 mV. When the roots were placed horizontally cortical cells on the upper side hyperpolarized to - 154 mV within 30 s while cortical cells on the lower side depolarized to about - 62 mV. This electrical asymmetry did not occur in cells of the maturation zone. Because attempts to insert the electrode into cells of the root cap were unsuccessful, these cells were not measured. The hyperpolarization of cortical cells on the upper side was greatly reduced upon application of N,N'-dicyclohexylcarbodiimide (DCCD), an inhibitor of respiratory energy coupling. When stimulated roots were returned to the vertical, the degree of hyperpolarization of cortical cells on the previous upper side decreased within 30 s and approached that of cortical cells in non-stimulated roots. This cycle of hyperpolarization/loss of hyperpolarization was repeatable at least ten times by alternately turning the root from the vertical to the horizontal and back again. The very short (<30 s) lag period of these electrical changes indicates that they may result from stimulus-perception and transduction within the elongation zone rather than from transmission of a signal from the root cap.

Ultrastructure of pea and cress root statocytes exposed to high gradient magnetic field

NASA Astrophysics Data System (ADS)

Belyavskaya, N. A.; Chernishov, V. I.; Polishchuk, O. V.; Kondrachuk, A. V.

As it was demonstrated by Kuznetsov & Hasenstein (1996) the high gradient magnetic field (HGMF) can produce a ponderomotive force that results in displacements of amyloplasts and causes the root response similar to the graviresponse. It was suggested that the HGMF could allow to imitate the effects of gravity in microgravity and/or change them in laboratory conditions correspondingly, as well as to study statolith-related processes in graviperception. Therefore, the correlation between the direction of the ponderomotive force resulting in statolith displacements and the direction of the HGMF-induced plant curvature can be the serious argument to support this suggestion and needs the detailed ultrastructural analysis. Seeds of dicotyledon Pisum sativum L. cv. Damir-2 and monocotyledon Lepidium sativum L. cv. P896 were soaked and grown in a vertical position on moist filter paper in chambers at room temperature. Tips of primary roots of vertical control, gravistimulated and exposed to HGMF seedlings were fixed for electron microscopy using conventional techniques. At ultrastructural level, we observed no significant changes in the volume of the individual statocytes or amyloplasts, relative volumes of cellular organelles (except vacuoles), number of amyloplasts per statocyte or surface area of endoplasmic reticulum. No consistent contacts between amyloplasts and any cellular structures, including plasma membrane, were revealed at any stage of magneto- and gravistimulation. By 5 min after onset of magnetostimulation, amyloplasts were located along cell wall distant from magnets. In HGMF, the locations of amyloplasts in columella cells were similar to those in horizontally-oriented roots up to 1 h stimulation. In the latter case, there were sometimes cytoplasmic spherical bodies with a dense vesicle-rich cytoplasm in pea statocytes, which were absent in seedlings exposed to HGMF. In cress root statocytes, both gravi- and magnetostimulation were found to cause the appearance of significant amounts of electron-dense granules in the cytoplasm and the nucleus (particularly, in the nucleolus); the effect was most evident in HGMF. Testing the chemical composition of such deposits is going on. The data presented statocyte responses indicate similarity the effects of magneto- and gravistimulation at the ultrastructural level. Thus, the root curvature in HGMF is the plant response to displacement of amyloplasts by ponderomotive force, which can serve as tool for investigation of graviperception mechanism and can provide directional stimulus for plant growth in microgravity. (Financial support by STCU: NN-13R).

Enceladus' 101 Geysers: Phantoms? Hardly

NASA Astrophysics Data System (ADS)

Porco, C.; Nimmo, F.; DiNino, D.

2015-12-01

The discovery by the Cassini mission of present-day geysering activity capping the southern hemisphere of Saturn's moon Enceladus (eg, Porco, C. C. et al. Science 311, 1393, 2006) and sourced within a subsurface body of liquid water (eg, Postberg, F. et al. Nature 459, 1098, 2009; Porco, C.C. et al. AJ 148, 45, 2014, hereafter PEA], laced with organic compounds (eg, Waite, J.H. et al. Science 311, 1419, 2006), has been a significant one, with far-reaching astrobiological implications. In an extensive Cassini imaging survey of the moon's south polar terrain (SPT), PEA identified 101 distinct, narrow jets of small icy particles erupting, with varying strengths, from the four major fractures crossing the SPT. A sufficient spread in stereo angles of the 107 images used in that work allowed (in some cases, many) pair-wise triangulations to be computed; precise surface locations were derived for 98 jets. Recently, it has been claimed (Spitale, J.N. et al. Nature 521, 57, 2015) that the majority of the geysers are not true discrete jets, but are "phantoms" that appear in shallow-angle views of a dense continuous curtain of material with acute bends in it. These authors also concluded that the majority of the eruptive material is not in the form of jets but in the form of fissure-style 'curtain' eruptions. We argue below the contrary, that because almost all the moon's geysers were identified by PEA using multiple images with favorable viewing geometries, the vast majority of them, and likely all, are discrete jets. Specifically, out of 98 jets, no fewer than 90 to 95 were identified with viewing geometries that preclude the appearance of phantoms. How the erupting solids (i.e., icy particles) that are seen in Cassini images are partitioned between jets and inter-jet curtains is still an open question.

Organelle sedimentation in gravitropic roots of Limnobium is restricted to the elongation zone

NASA Technical Reports Server (NTRS)

Sack, F. D.; Kim, D.; Stein, B.

1994-01-01

Roots of the aquatic angiosperm Limnobium spongia (Bosc) Steud. were evaluated by light and electron microscopy to determine the distribution of organelle sedimentation towards gravity. Roots of Limnobium are strongly gravitropic. The rootcap consists of only two layers of cells. Although small amyloplasts are present in the central cap cells, no sedimentation of any organelle, including amyloplasts, was found. In contrast, both amyloplasts and nuclei sediment consistently and completely in cells of the elongation zone. Sedimentation occurs in one cell layer of the cortex just outside the endodermis. Sedimentation of both amyloplasts and nuclei begins in cells that are in their initial stages of elongation and persists at least to the level of the root where root hairs emerge. This is the first modern report of the presence of sedimentation away from, but not in, the rootcap. It shows that sedimentation in the rootcap is not necessary for gravitropic sensing in at least one angiosperm. If amyloplast sedimentation is responsible for gravitropic sensing, then the site of sensing in Limnobium roots is the elongation zone and not the rootcap. These data do not necessarily conflict with the hypothesis that sensing occurs in the cap in other roots, since Limnobium roots are exceptional in rootcap origin and structure, as well as in the distribution of organelle sedimentation. Similarly, if nuclear sedimentation is involved in gravitropic sensing, then nuclear mass would function in addition to, not instead of, that of amyloplasts.

Greenhouse Studies of Thiamethoxam Effects on Pea Leaf Weevil, Sitona lineatus

PubMed Central

Cárcamo, Héctor; Herle, Carolyn; Hervet, Vincent

2012-01-01

The pea leaf weevil, Sitona lineatus L. (Coleoptera: Curculionidae), has recently emerged as an important pest of field peas in the Canadian prairies. Systemic seed-coated insecticides may provide a tool for the integrated pest management of this pest. Therefore, several controlled assays were performed in order to determine effects of a recently registered neonicotinoid, (thiamethoxam) on S. lineatus damage to foliage, weevil mortality, fertility, egg viability, larval mortality, and root nodule damage. Foliage damage was reduced by thiamethoxam relative to untreated controls during the seedling stage (2nd–5th nodes), but weevil adult mortality was only 15–30%. Fertility was reduced substantially through an extra seven-day delay in the preoviposition period and reduced egg-laying rate during the first 20 days of the study (92% lower than controls). Overall egg viability was lower in females fed foliage grown from thiamethoxamtreated seeds. Larval survivorship and nodule damage were also lower, but only when eggs were added to treated plants at the 2nd node stage. When eggs were added late, at the 5th node stage, thiamethoxam had no effect on larval survivorship or nodule damage. The results of this study led to the conclusion that seed treatments such as thiamethoxam have potential to be used as tools that will aid in the integrated pest management of S. lineatus, especially in combination with other methods such as biocontrol and trap crops. PMID:23461362

Reliability and Validity of the Physical Education Activities Scale.

PubMed

Thomason, Diane L; Feng, Du

2016-06-01

Measuring adolescent perceptions of physical education (PE) activities is necessary in understanding determinants of school PE activity participation. This study assessed reliability and validity of the Physical Education Activities Scale (PEAS), a 41-item visual analog scale measuring high school adolescent perceptions of school PE activity participation. Adolescents (N = 529) from the Pacific Northwest aged 15-19 in grades 9-12 participated in the study. Construct validity was assessed using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). Measurement invariance across sex groups was tested by multiple-group CFA. Internal consistency reliability was analyzed using Cronbach's alpha. Inter-subscale correlations (Pearson's r) were calculated for latent factors and observed subscale scores. Exploratory factor analysis suggested a 3-factor solution explaining 43.4% of the total variance. Confirmatory factor analysis showed the 3-factor model fit the data adequately (comparative fit index [CFI] = 0.90, Tucker-Lewis index [TLI] = 0.89, root mean squared error of approximation [RMSEA] = 0.063). Factorial invariance was supported. Cronbach's alpha of the total PEAS was α = 0.92, and for subscales α ranged from 0.65 to 0.92. Independent t-tests showed significantly higher mean scores for boys than girls on the total scale and all subscales. Findings provide psychometric support for using the PEAS for examining adolescent's psychosocial and environmental perceptions to participating in PE activities. © 2016, American School Health Association.

Protein import into isolated pea root leucoplasts.

PubMed

Chu, Chiung-Chih; Li, Hsou-Min

2015-01-01

Leucoplasts are important organelles for the synthesis and storage of starch, lipids and proteins. However, molecular mechanism of protein import into leucoplasts and how it differs from that of import into chloroplasts remain unknown. We used pea seedlings for both chloroplast and leucoplast isolations to compare within the same species. We further optimized the isolation and import conditions to improve import efficiency and to permit a quantitative comparison between the two plastid types. The authenticity of the import was verified using a mitochondrial precursor protein. Our results show that, when normalized to Toc75, most translocon proteins are less abundant in leucoplasts than in chloroplasts. A precursor shown to prefer the receptor Toc132 indeed had relatively more similar import efficiencies between chloroplasts and leucoplasts compared to precursors that prefer Toc159. Furthermore we found two precursors that exhibited very high import efficiency into leucoplasts. Their transit peptides may be candidates for delivering transgenic proteins into leucoplasts and for analyzing motifs important for leucoplast import.

Analysis of AtGUS1 and AtGUS2 in Arabidopsis root apex by a highly sensitive TSA-MISH method.

PubMed

Bruno, Leonardo; Ronchini, Matteo; Gagliardi, Olimpia; Corinti, Tamara; Chiappetta, Adriana; Gerola, Paolo; Bitonti, Maria B

2015-01-01

A new highly sensitive whole-mount in situ hybridization method, based on tyramide signal amplification (TSA-MISH) was developed and a combined GFP detection and TSA-MISH procedure was applied for the first time in plants, to precisely define the spatial pattern of AtGUS1 and AtGUS2 expression in the root apex. β-glucuronidases (GUSs) belonging to the glycosyl hydrolases (GHs) 79 family, are widely distributed in plants, but their functional role has not yet been fully investigated. In the model system Arabidopsis Thaliana, three different AtGUS genes have been identified which encode proteins with putative different fates. Endogenous GUS expression has been detected in different organs and tissues, but the cyto-histological domains of gene expression remain unclear. The results here reported show co-expression of AtGUS1 and AtGUS2 in different functional zones of the root apex (the cap central zone, the root cap meristem, the staminal cell niche and the cortical cell layers of the proximal meristem), while AtGUS2 is exclusively expressed in the cap peripheral layer and in the epidermis in the elongation zone. Interestingly, both genes are not expressed in the stelar portion of the proximal meristem. A spatial (cortex vs. stele) and temporal (proximal meristem vs. transition zone) regulation of AtGUS1 and AtGUS2 expression is therefore active in the root apex. This expression pattern, although globally consistent with the involvement of GUS activity in both cell proliferation and elongation, clearly indicates that AtGUS1 and AtGUS2 could control distinct downstream process depending on the developmental context and the interaction with other players of root growth control. In the future, the newly developed approaches may well be very useful to dissect such interactions.

Induction of host defences by Rhizobium during ineffective nodulation of pea (Pisum sativum L.) carrying symbiotically defective mutations sym40 (PsEFD), sym33 (PsIPD3/PsCYCLOPS) and sym42.

PubMed

Ivanova, Kira A; Tsyganova, Anna V; Brewin, Nicholas J; Tikhonovich, Igor A; Tsyganov, Viktor E

2015-11-01

Rhizobia are able to establish a beneficial interaction with legumes by forming a new organ, called the symbiotic root nodule, which is a unique ecological niche for rhizobial nitrogen fixation. Rhizobial infection has many similarities with pathogenic infection and induction of defence responses accompanies both interactions, but defence responses are induced to a lesser extent during rhizobial infection. However, strong defence responses may result from incompatible interactions between legumes and rhizobia due to a mutation in either macro- or microsymbiont. The aim of this research was to analyse different plant defence reactions in response to Rhizobium infection for several pea (Pisum sativum) mutants that result in ineffective symbiosis. Pea mutants were examined by histochemical and immunocytochemical analyses, light, fluorescence and transmission electron microscopy and quantitative real-time PCR gene expression analysis. It was observed that mutations in pea symbiotic genes sym33 (PsIPD3/PsCYCLOPS encoding a transcriptional factor) and sym40 (PsEFD encoding a putative negative regulator of the cytokinin response) led to suberin depositions in ineffective nodules, and in the sym42 there were callose depositions in infection thread (IT) and host cell walls. The increase in deposition of unesterified pectin in IT walls was observed for mutants in the sym33 and sym42; for mutant in the sym42, unesterified pectin was also found around degrading bacteroids. In mutants in the genes sym33 and sym40, an increase in the expression level of a gene encoding peroxidase was observed. In the genes sym40 and sym42, an increase in the expression levels of genes encoding a marker of hypersensitive reaction and PR10 protein was demonstrated. Thus, a range of plant defence responses like suberisation, callose and unesterified pectin deposition as well as activation of defence genes can be triggered by different pea single mutations that cause perception of an otherwise beneficial strain of Rhizobium as a pathogen.

Genetical approach to gravitropism

NASA Astrophysics Data System (ADS)

Boonsirichai, K.; Chen, R.; Guan, C.; Rosen, E.; Young, L.; Masson, P.

Gravitropism guides the growth of plant organs at a defined angle from the gravity vector. Accordingly, most roots grow downward, undergoing positive gravitropism. Gravity perception by roots appears to involve the sedimentation of amyloplasts within the columella cells of the cap. Amyloplast sedimentation triggers a signal transduction pathway that promotes the development of an auxin gradient across the root tip. This gradient is then transmitted to the elongation zones where it promotes a differential cellular elongation, partly responsible for the development of a root-tip curvature. To better understand the mechanisms involved in gravity signal transduction, we have identified and characterized several Arabidopsis thaliana mutants that show specific defects in root gravitropism. Several of these genes were characterized. ARG1 functions in gravity signal transduction, and encodes a dnaJ-like protein whose structure suggests an interaction with the cytoskeleton. Two other genes encode similar proteins (ARL1 and ARL2) in Arabidopsis. One of them (ARL2) also appears to function in gravity signal transduction. Because loss-of-function mutations in ARG1 result in partial alterations of gravitropism, we were able to identify and characterize two genetic enhancers of arg1-2: mar1-1 and mar2-1. These enhancers increased the gravitropism defect of arg1-2 roots and hypocotyls, and changed its orientation. Hence, MAR1 and MAR2 also appear to function in gravity signal transduction. AGR1, on the other hand, encodes a transmembrane component of the auxin efflux carrier complex involved in polar auxin transport through the elongation zones of Arabidopsis root tips. It belongs to a large gene family, several members of which are expressed in the root cap. Upon gravistimulation, the AGR3 protein appears to quickly relocate within the columella cells, accumulating in membranes at the new physical bottom. Hence, the gravity signal transduction pathway that includes the ARG1, ARL2, MAR1 and MAR2 gene products, appears to control the cellular distribution of auxin efflux carriers in the columella cells of the root cap, thereby controlling the polarity of lateral auxin transport in response to gravistimulation. Work is in progress to identify new proteins that interact genetically or physically with ARG1, ARL2 or AGR1, and characterize their involvement in gravitropism.

Development of Rhizo-Columns for Nondestructive Root System Architecture Laboratory Measurements

NASA Astrophysics Data System (ADS)

Oostrom, M.; Johnson, T. J.; Varga, T.; Hess, N. J.; Wietsma, T. W.

2016-12-01

Numerical models for root water uptake in plant-soil systems have been developing rapidly, increasing the demand for laboratory experimental data to test and verify these models. Most of the increasingly detailed models are either compared to long-term field crop data or do not involve comparisons at all. Ideally, experiments would provide information on dynamic root system architecture (RSA) in combination with soil-pant hydraulics such as water pressures and volumetric water contents. Data obtained from emerging methods such as Spectral Induced Polarization (SIP) and x-ray computed tomography (x-ray CT) may be used to provide laboratory RSA data needed for model comparisons. Point measurements such as polymer tensiometers (PT) may provide soil moisture information over a large range of water pressures, from field capacity to the wilting point under drought conditions. In the presentation, we demonstrate a novel laboratory capability allowing for detailed RSA studies in large columns under controlled conditions using automated SIP, X-ray CT, and PT methods. Examples are shown for pea and corn root development under various moisture regimes.

Changes in the topography of cellular components in pea root statocytes exposed to high gradient magnetic fields

NASA Astrophysics Data System (ADS)

Belyavskaya, Ninel A.; Polishchuk, Olexandr V.; Kondrachuk, Alexander V.

2005-08-01

High-gradient magnetic field (HGMF) is one of methods, by which gravitropism in plants is studied. The aim of our study was elucidation of HGMF effects on topography of cellular components in root statocytes of 4- day Pisum sativum L. seedlings in comparison to gravistimulation. Under gravistimulation during 5, 30 and 60 min seedlings were rotated 45o; magnetostimulation was carried out along gap between two NdFeB magnets (0.7 T). Morphometric measurements were made from images of whole statocytes, for upper, middle and lower thirds of cells, and proximal and distal halves of cells. Morphometric analysis revealed that HGMF resulted in the redistribution of all cellular components in statocytes. The correlation in the amyloplast distribution between gravistimulation and magnetostimulation was established.

Ammonium affects cell viability to inhibit root growth in Arabidopsis * #

PubMed Central

Qin, Cheng; Yi, Ke-ke; Wu, Ping

2011-01-01

Ammonium (NH4 +) is an important form of nitrogen nutrient for most plants, yet is also a stressor for many of them. However, the primary events of NH4 + toxicity at the cellular level are still unclear. Here, we showed that NH4 + toxicity can induce the root cell death in a temporal pattern which primarily occurs in the cells of root maturation and elongation zones, and then spreads to the cells in the meristem and root cap. The results from the NH4 +-hypersensitive mutant hsn1 further confirmed our findings. Taken together, NH4 + toxicity inhibits primary root growth by inhibiting cell elongation and division and inducing root cell death. PMID:21634041

Discriminative stimulus properties of beta-phenylethylamine, deuterated beta-phenylethylamine, phenylethanolamine and some metabolites of phenylethylamine in rodents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reid, D.; Goudie, A.J.

The discriminative stimulus (cue) properties of phenylethylamine (PEA) were analysed in rodents in a conventional two lever FR10 operant drug discrimination task. Rats trained to discriminate phenylethylamine at 30 mg/kg showed complete dose-related generalization to PEA and to two potential PEA metabolites: phenylethanolamine (PEOH) and N-Methyl PEA (NMPEA). Only partial (50%) generalization was seen with N-Methylphenylethanolamine (NMPEOH), another potential PEA metabolite. The specificity of PEA's action as a discriminative stimulus was demonstrated by the finding that fenfluramine, a substituted phenylethylamine, failed to generalize to PEA even at high doses with marked behavioural effects which are known to have discriminative stimulusmore » properties themselves. These data suggest that NMPEA and PEOH may be functionally important active metabolites of PEA, particularly if the major pathway of PEA metabolism to phenylacetic acid under the influence of MAO Type B is for any reason impaired. A long acting deuterium substituted form of PEA (alpha, alpha, d2 PEA), which is resistant to metabolism by MAO, produced complete dose-related generalization to the PEA cue but was more potent than PEA, due presumably to its resistance to metabolism by MAO. Deuterated PEA may therefore be a useful agent to use in future studies of the PEA cue, because the discriminability of PEA itself appears to be low due to its very rapid metabolism in vivo.« less

Ethylene Upregulates Auxin Biosynthesis in Arabidopsis Seedlings to Enhance Inhibition of Root Cell Elongation[W

PubMed Central

Swarup, Ranjan; Perry, Paula; Hagenbeek, Dik; Van Der Straeten, Dominique; Beemster, Gerrit T.S.; Sandberg, Göran; Bhalerao, Rishikesh; Ljung, Karin; Bennett, Malcolm J.

2007-01-01

Ethylene represents an important regulatory signal for root development. Genetic studies in Arabidopsis thaliana have demonstrated that ethylene inhibition of root growth involves another hormone signal, auxin. This study investigated why auxin was required by ethylene to regulate root growth. We initially observed that ethylene positively controls auxin biosynthesis in the root apex. We subsequently demonstrated that ethylene-regulated root growth is dependent on (1) the transport of auxin from the root apex via the lateral root cap and (2) auxin responses occurring in multiple elongation zone tissues. Detailed growth studies revealed that the ability of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid to inhibit root cell elongation was significantly enhanced in the presence of auxin. We conclude that by upregulating auxin biosynthesis, ethylene facilitates its ability to inhibit root cell expansion. PMID:17630275

Evaluation of Linear, Inviscid, Viscous, and Reduced-Order Modeling Aeroelastic Solutions of the AGARD 445.6 Wing Using Root Locus Analysis

NASA Technical Reports Server (NTRS)

Silva, Walter A.; Perry, Boyd III; Chwalowski, Pawel

2014-01-01

Reduced-order modeling (ROM) methods are applied to the CFD-based aeroelastic analysis of the AGARD 445.6 wing in order to gain insight regarding well-known discrepancies between the aeroelastic analyses and the experimental results. The results presented include aeroelastic solutions using the inviscid CAP-TSD code and the FUN3D code (Euler and Navier-Stokes). Full CFD aeroelastic solutions and ROM aeroelastic solutions, computed at several Mach numbers, are presented in the form of root locus plots in order to better reveal the aeroelastic root migrations with increasing dynamic pressure. Important conclusions are drawn from these results including the ability of the linear CAP-TSD code to accurately predict the entire experimental flutter boundary (repeat of analyses performed in the 1980's), that the Euler solutions at supersonic conditions indicate that the third mode is always unstable, and that the FUN3D Navier-Stokes solutions stabilize the unstable third mode seen in the Euler solutions.

The Application of Contrast Media for In Vivo Feature Enhancement in X-Ray Computed Tomography of Soil-Grown Plant Roots.

PubMed

Keyes, Samuel D; Gostling, Neil J; Cheung, Jessica H; Roose, Tiina; Sinclair, Ian; Marchant, Alan

2017-06-01

The use of in vivo X-ray microcomputed tomography (μCT) to study plant root systems has become routine, but is often hampered by poor contrast between roots, soil, soil water, and soil organic matter. In clinical radiology, imaging of poorly contrasting regions is frequently aided by the use of radio-opaque contrast media. In this study, we present evidence for the utility of iodinated contrast media (ICM) in the study of plant root systems using μCT. Different dilutions of an ionic and nonionic ICM (Gastrografin 370 and Niopam 300) were perfused into the aerial vasculature of juvenile pea plants via a leaf flap (Pisum sativum). The root systems were imaged via μCT, and a variety of image-processing approaches used to quantify and compare the magnitude of the contrast enhancement between different regions. Though the treatment did not appear to significantly aid extraction of full root system architectures from the surrounding soil, it did allow the xylem and phloem units of seminal roots and the vascular morphology within rhizobial nodules to be clearly visualized. The nonionic, low-osmolality contrast agent Niopam appeared to be well tolerated by the plant, whereas Gastrografin showed evidence of toxicity. In summary, the use of iodine-based contrast media allows usually poorly contrasting root structures to be visualized nondestructively using X-ray μCT. In particular, the vascular structures of roots and rhizobial nodules can be clearly visualized in situ.

Modelling the impact of climatic conditions and plant species on the nitrogen release from mulch of legumes at the soil surface

NASA Astrophysics Data System (ADS)

Gaudinat, Germain; Lorin, Mathieu; Valantin-morison, Muriel; Garnier, Patricia

2015-04-01

Cover crops provide multiple services to the agro ecosystem. Among them, the use of legumes as cover crop is one of the solutions for limiting the use of herbicides, mineral fertilizers, and insecticides. However, the dynamic of mineralization is difficult to understand because of the difficulty of measuring nitrogen release from mulch in field. Indeed, residues are degraded at the soil surface as mulch, while the nitrogen uptake by the main crop occurred simultaneously in the soil. This work aims to study the dynamics of nitrogen mineralization from legume residues through i) the use of a model able to describe the physical and biological dynamic of mulch and ii) a data set from a field experiment of intercropping systems "oilseed rape-legumes" from different species (grass pea, lentil, Berseem clover, field pea, vetch). The objective of the simulations is to identify the variations of expected quantities of nitrogen from different legumes. The soil-plant model of mulch decomposition PASTIS-Mulch was used to determine the nitrogen supply from mulch available for rapeseed. These simulation results were compared to the data collected in the experimental field of Grignon (France). We performed analyzes of biochemical and physical characteristics of legume residues and monitored the evolution of mulches (moisture, density, cover surface, biomass) in fields. PASTIS simulations of soil temperature, soil moisture, mulch humidity and mulch decomposition were close to the experimental results. The PASTIS model was suitable to simulate the dynamic of legume mulches in the case of "rape - legume" associations. The model simulated nitrogen restitution of aerial and root parts. We found a more rapid nitrogen release by grass pea than other species. Vetch released less nitrogen than the other species. The scenarios for climate conditions were : i) a freezing in December that causes the destruction of plants, or a destruction by herbicide in March, ii) a strong or a weak rainy spring. Climatic conditions had a strong impact on the simulated release of nitrogen. Nitrogen supply was higher when degradation begun early with a rainy spring. Conversely, the degradation was lower when the degradation started late with a dry spring. Root release was less sensitive to climate and most of the nitrogen in the roots returned to the soil in a few weeks. The impact of "species" on the decomposition was explained not only by their chemical properties but also by their physical properties. The climatic conditions had different effects according to the species.

Amino Acid Derivatives as Palmitoylethanolamide Prodrugs: Synthesis, In Vitro Metabolism and In Vivo Plasma Profile in Rats

PubMed Central

Vacondio, Federica; Bassi, Michele; Silva, Claudia; Castelli, Riccardo; Carmi, Caterina; Scalvini, Laura; Lodola, Alessio; Vivo, Valentina; Flammini, Lisa; Barocelli, Elisabetta; Mor, Marco; Rivara, Silvia

2015-01-01

Palmitoylethanolamide (PEA) has antinflammatory and antinociceptive properties widely exploited in veterinary and human medicine, despite its poor pharmacokinetics. Looking for prodrugs that could progressively release PEA to maintain effective plasma concentrations, we prepared carbonates, esters and carbamates at the hydroxyl group of PEA. Chemical stability (pH 7.4) and stability in rat plasma and liver homogenate were evaluated by in vitro assays. Carbonates and carbamates resulted too labile and too resistant in plasma, respectively. Ester derivatives, prepared by conjugating PEA with various amino acids, allowed to modulate the kinetics of PEA release in plasma and stability in liver homogenate. L-Val-PEA, with suitable PEA release in plasma, and D-Val-PEA, with high resistance to hepatic degradation, were orally administered to rats and plasma levels of prodrugs and PEA were measured at different time points. Both prodrugs showed significant release of PEA, but provided lower plasma concentrations than those obtained with equimolar doses of PEA. Amino-acid esters of PEA are a promising class to develop prodrugs, even if they need further chemical optimization. PMID:26053855

Influence of electrical fields and asymmetric application of mucilage on curvature of primary roots of Zea mays

NASA Technical Reports Server (NTRS)

Marcum, H.; Moore, R.

1990-01-01

Primary roots of Zea mays cv. Yellow Dent growing in an electric field curve towards the anode. Roots treated with EDTA and growing in electric field do not curve. When root cap mucilage is applied asymmetrically to tips of vertically-oriented roots, the roots curve toward the mucilage. Roots treated with EDTA curve toward the side receiving mucilage and toward blocks containing 10 mM CaCl2, but not toward "empty" agar blocks or the cut surfaces of severed root tips. These results suggest that 1) free calcium (Ca) is necessary for root electrotropism, 2) mucilage contains effector(s) that induce gravitropiclike curvature, and 3) mucilage can replace gravitropic effectors chelated by EDTA. These results are consistent with the hypothesis that the downward movement of gravitropic effectors to the lower sides of tips of horizontally-oriented roots occurs at least partially in the apoplast.

[14C]-beta-phenethylamine, its distribution after administration by various routes to cats, and the effects of monoamine oxidase inhibitors.

PubMed Central

Garcha, G.; Imrie, P. R.; Marley, E.; Thomas, D. V.

1985-01-01

[14C]-beta-phenethylamine [( 14C]-PEA) was instilled intragastrically, intraduodenally (i.d.) or infused into the portal vein or femoral artery of cats, anaesthetized with chloralose, to investigate its distribution in the body. [14C]-PEA and phenylacetic acid (PAA) accounted for approximately 85% of radioactivity recovered in blood from control cats or those pretreated with deprenyl or mebanazine. Progressively greater portal venous (PV), cranial mesenteric arterial (CMA) and PV-CMA concentrations of PEA and PAA were observed with increase in amount of PEA instilled intraduodenally (i.d.); PAA predominated over PEA, more so in CMA than PV blood. Radioactivity was not recovered from blood following intragastric instillation of PEA. When histamine 1.7 mumol kg-1, i.d., was combined with PEA 1.7 mumol kg-1, i.d., or tyramine 8.5 mumol kg-1, i.d., was combined with PEA 8.5 mumol kg-1, i.d., PV-CMA values for PEA were significantly augmented. Arterial concentrations of PEA were increased 3.5 to 5 fold compared to controls by pretreatment with mebanazine or deprenyl plus clorgyline; arterial concentrations of PAA were reduced. PEA blood concentrations were not significantly altered by clorgyline or deprenyl pretreatment. Infusion of PEA 680, 1020 or 1360 nmol kg-1 min-1 for 20 min into the portal vein raised blood pressure 60 to 100 mmHg (at a PEA concentration of ca, 2 nmol ml-1) but lacked effect on the nictitating membrane despite peak arterial PEA concentrations of 20 nmol ml-1; in cats pretreated with mebanazine or clorgyline plus deprenyl, half-maximum contraction of the nictitating membrane occurred with arterial PEA concentrations of 4.8 to 9 nmol ml-1. In cats pretreated with mebanazine or deprenyl plus clorgyline, half maximum contraction of the nictitating membrane was elicited also by intraduodenal PEA 8.5 mumol kg-1 at arterial PEA concentrations of ca. 2 nmol ml-1, despite lack of effect of PEA 17 mumol kg-1, i.d., in control cats with a peak arterial PEA concentration of 1.8 nmol ml-1. [14C]-PEA and PAA were recovered from liver, kidney, distal small intestine, lung, arterial vessel walls, skeletal muscle, brain, foetus and amniotic liquor, after PEA instilled i.d., overall concentration of PEA exceeding that of PAA except in the kidney. The combined amount of PEA and PAA in kidney was 7 to 20 fold that in other tissues. PEA content of tissues was significantly elevated and that of PAA diminished by pretreatment with deprenyl plus clorgyline, and to a lesser extent after mebanazine. PMID:4075021

Bean alpha-amylase inhibitors in transgenic peas inhibit development of pea weevil larvae.

PubMed

de Sousa-Majer, Maria José; Hardie, Darryl C; Turner, Neil C; Higgins, Thomas J V

2007-08-01

This glasshouse study used an improved larval measurement procedure to evaluate the impact of transgenic pea, Pisum sativum L., seeds expressing a-amylase inhibitor (AI)-1 or -2 proteins on pea weevil, Bruchus pisorum L. Seeds of transgenic 'Laura' and 'Greenfeast' peas expressing alpha-(AI)-1 reduced pea weevil survival by 93-98%. Larval mortality occurred at an early instar. Conversely, in nontransgenic cultivars, approximately 98-99% of the pea weevils emerged as adults. By measuring the head capsule size, we determined that larvae died at the first to early third instar in alpha-(AI)-1 transgenic peas, indicating that this inhibitor is highly effective in controlling this insect. By contrast, transgenic Laura and 'Dundale' expressing alpha-(AI)-2 did not affect pea weevil survival, but they did delay larval development. After 77 d of development, the head capsule size indicated that the larvae were still at the third instar stage in transgenic alpha-(AI)-2 peas, whereas adult bruchids had developed in the nontransgenic peas.

Ashwagandha

MedlinePlus

... specific ashwagandha root extract (KSM66, Ixoreal Biomed, Hyderabad, India) 300 mg twice daily after food for 60 ... Cap Strelaxin, M/s Pharmanza Herbal Pvt. Ltd., Gujarat, India) 400 mg three times daily for one month ...

Comparative Transcriptomic Analyses of Vegetable and Grain Pea (Pisum sativum L.) Seed Development

PubMed Central

Liu, Na; Zhang, Guwen; Xu, Shengchun; Mao, Weihua; Hu, Qizan; Gong, Yaming

2015-01-01

Understanding the molecular mechanisms regulating pea seed developmental process is extremely important for pea breeding. In this study, we used high-throughput RNA-Seq and bioinformatics analyses to examine the changes in gene expression during seed development in vegetable pea and grain pea, and compare the gene expression profiles of these two pea types. RNA-Seq generated 18.7 G of raw data, which were then de novo assembled into 77,273 unigenes with a mean length of 930 bp. Our results illustrate that transcriptional control during pea seed development is a highly coordinated process. There were 459 and 801 genes differentially expressed at early and late seed maturation stages between vegetable pea and grain pea, respectively. Soluble sugar and starch metabolism related genes were significantly activated during the development of pea seeds coinciding with the onset of accumulation of sugar and starch in the seeds. A comparative analysis of genes involved in sugar and starch biosynthesis in vegetable pea (high seed soluble sugar and low starch) and grain pea (high seed starch and low soluble sugar) revealed that differential expression of related genes at late development stages results in a negative correlation between soluble sugar and starch biosynthetic flux in vegetable and grain pea seeds. RNA-Seq data was validated by using real-time quantitative RT-PCR analysis for 30 randomly selected genes. To our knowledge, this work represents the first report of seed development transcriptomics in pea. The obtained results provide a foundation to support future efforts to unravel the underlying mechanisms that control the developmental biology of pea seeds, and serve as a valuable resource for improving pea breeding. PMID:26635856

Internode length in Pisum. Gene na may block gibberellin synthesis between ent-7. cap alpha. -hydroxykaurenoic acid and biggerellin A/sub 12/-aldehyde. [Pisum sativum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ingram, T.J.; Reid, J.B.

1987-04-01

The elongation response of the gibberellin (GA) deficient genotypes na, ls, and lh of peas (Pisum sativum L.) to a range of GA-precursors was examined. Plants possessing gene na did not respond to precursors in the GA biosynthetic pathway prior to GA/sub 12/-aldehyde. In contrast, plants possessing lh and ls responded as well as wild-type plants (dwarfed with AMO-1618) to these compounds. The results suggest that GA biosynthesis is blocked prior to ent-kaurene in the lh and ls mutants and between ent-7..cap alpha..-hydroxykaurenoic acid and GA/sub 12/-aldehyde in the na mutant. Feeds of ent(/sup 3/H)kaurenoic acid and (/sup 2/H)GA/sub 12/-aldehydemore » to a range of genotypes supported the above conclusions. The na line WL1766 was shown by gas chromatography-mass spectrometry (GC-MS) to metabolize(/sup 2/H)GA/sub 12/-aldehyde to a number of (/sup 2/H)C/sub 19/-GAs including GA/sub 1/. However, there was no indication in na genotypes for the metabolism of ent-(/sup 3/H)kaurenoic acid to these GAs. In contrast, the expanding shoot tissue of all Na genotypes examined metabolized ent-(/sup 3/H)kaurenoic acid to radioactive compounds that co-chromatographed with GA/sub 1/, GA/sub 8/, GA/sub 20/, and GA/sub 29/. However, insufficient material was present for unequivocal identification of the metabolites. The radioactive profiles from HPLC of extracts of the node treated with ent-(/sup 3/H)kaurenoic acid were similar for both Na and na plants and contained ent-16..cap alpha..,17-dihydroxykaurenoic acid and ent-6..cap alpha..,7..cap alpha..,16..beta..,17-tetrahydroxykaurenoic acid (both characterized by GC-MS), suggesting that the metabolites arose from side branches of the main GA-biosynthetic pathway. Thus, both Na and na plants appear capable of ent-7..cap alpha..-hydroxylation.« less

Polyamines cause plasma membrane depolarization, activate Ca2+-, and modulate H+-ATPase pump activity in pea roots.

PubMed

Pottosin, Igor; Velarde-Buendía, Ana María; Bose, Jayakumar; Fuglsang, Anja T; Shabala, Sergey

2014-06-01

Polyamines regulate a variety of cation and K(+) channels, but their potential effects on cation-transporting ATPases are underexplored. In this work, noninvasive microelectrode ion flux estimation and conventional microelectrode techniques were applied to study the effects of polyamines on Ca(2+) and H(+) transport and membrane potential in pea roots. Externally applied spermine or putrescine (1mM) equally activated eosin yellow (EY)-sensitive Ca(2+) pumping across the root epidermis and caused net H(+) influx or efflux. Proton influx induced by spermine was suppressed by EY, supporting the mechanism in which Ca(2+) pump imports 2 H(+) per each exported Ca(2+). Suppression of the Ca(2+) pump by EY diminished putrescine-induced net H(+) efflux instead of increasing it. Thus, activities of Ca(2+) and H(+) pumps were coupled, likely due to the H(+)-pump inhibition by intracellular Ca(2+). Additionally, spermine but not putrescine caused a direct inhibition of H(+) pumping in isolated plasma membrane vesicles. Spermine, spermidine, and putrescine (1mM) induced membrane depolarization by 70, 50, and 35 mV, respectively. Spermine-induced depolarization was abolished by cation transport blocker Gd(3+), was insensitive to anion channels' blocker niflumate, and was dependent on external Ca(2+). Further analysis showed that uptake of polyamines but not polyamine-induced cationic (K(+)+Ca(2+)+H(+)) fluxes were a main cause of membrane depolarization. Polyamine increase is a common component of plant stress responses. Activation of Ca(2+) efflux by polyamines and contrasting effects of polyamines on net H(+) fluxes and membrane potential can contribute to Ca(2+) signalling and modulate a variety of transport processes across the plasma membrane under stress. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Genetic Analysis of Gravity Signal Transduction in Arabidopsis thaliana Seedlings

NASA Astrophysics Data System (ADS)

Boonsirichai, K.; Harrison, B.; Stanga, J.; Young, L.-S.; Neal, C.; Sabat, G.; Murthy, N.; Harms, A.; Sedbrook, J.; Masson, P.

The primary roots of Arabidopsis thaliana seedlings respond to gravity stimulation by developing a tip curvature that results from differential cellular elongation on opposite flanks of the elongation zone. This curvature appears modulated by a lateral gradient of auxin that originates in the gravity-perceiving cells (statocytes) of the root cap through an apparent lateral repositioning of a component the auxin efflux carrier complex within these cells (Friml et al, 2002, Nature 415: 806-809). Unfortunately, little is known about the molecular mechanisms that govern early phases of gravity perception and signal transduction within the root-cap statocytes. We have used a molecular genetic approach to uncover some of these mechanisms. Mutations in the Arabidopsis ARG1 and ARL2 genes, which encode J-domain proteins, resulted in specific alterations in root and hypocotyl gravitropism, without pleiotropic phenotypes. Interestingly, ARG1 and ARL2 appear to function in the same genetic pathway. A combination of molecular genetic, biochemical and cell-biological approaches were used to demonstrate that ARG1 functions in early phases of gravity signal transduction within the root and hypocotyl statocytes, and is needed for efficient lateral auxin transport within the cap. The ARG1 protein is associated with components of the secretory and/or endosomal pathways, suggesting its role in the recycling of components of the auxin efflux carrier complex between plasma membrane and endosome (Boonsirichai et al, 2003, Plant Cell 15:2612-2625). Genetic modifiers of arg1-2 were isolated and shown to enhance the gravitropic defect of arg1-2, while resulting in little or no gravitropic defects in a wild type ARG1 background. A slight tendency for arg1-2;mar1-1 and arg1-2;mar2-1 double-mutant organs to display an opposite gravitropic response compared to wild type suggests that all three genes contribute to the interpretation of the gravity-vector information by seedling organs. The molecular structure of these new loci is being investigated. Furthermore, a proteomic approach is being developed to characterize root-tip proteins that are differentially expressed, modified or targeted in response to gravity stimulation. We acknowledge funding by NASA and NSF.

Nemesia Root Hair Response to Paper Pulp Substrate for Micropropagation

PubMed Central

Labrousse, Pascal; Delmail, David; Decou, Raphaël; Carlué, Michel; Lhernould, Sabine; Krausz, Pierre

2012-01-01

Agar substrates for in vitro culture are well adapted to plant micropropagation, but not to plant rooting and acclimatization. Conversely, paper-pulp-based substrates appear as potentially well adapted for in vitro culture and functional root production. To reinforce this hypothesis, this study compares in vitro development of nemesia on several substrates. Strong differences between nemesia roots growing in agar or in paper-pulp substrates were evidenced through scanning electron microscopy. Roots developed in agar have shorter hairs, larger rhizodermal cells, and less organized root caps than those growing on paper pulp. In conclusion, it should be noted that in this study, in vitro microporous substrates such as paper pulp lead to the production of similar root hairs to those found in greenhouse peat substrates. Consequently, if agar could be used for micropropagation, rooting, and plant acclimatization, enhancement could be achieved if rooting stage was performed on micro-porous substrates such as paper pulp. PMID:22312323

Nemesia root hair response to paper pulp substrate for micropropagation.

PubMed

Labrousse, Pascal; Delmail, David; Decou, Raphaël; Carlué, Michel; Lhernould, Sabine; Krausz, Pierre

2012-01-01

Agar substrates for in vitro culture are well adapted to plant micropropagation, but not to plant rooting and acclimatization. Conversely, paper-pulp-based substrates appear as potentially well adapted for in vitro culture and functional root production. To reinforce this hypothesis, this study compares in vitro development of nemesia on several substrates. Strong differences between nemesia roots growing in agar or in paper-pulp substrates were evidenced through scanning electron microscopy. Roots developed in agar have shorter hairs, larger rhizodermal cells, and less organized root caps than those growing on paper pulp. In conclusion, it should be noted that in this study, in vitro microporous substrates such as paper pulp lead to the production of similar root hairs to those found in greenhouse peat substrates. Consequently, if agar could be used for micropropagation, rooting, and plant acclimatization, enhancement could be achieved if rooting stage was performed on micro-porous substrates such as paper pulp.

Boron Supply Enhances Aluminum Tolerance in Root Border Cells of Pea (Pisum sativum) by Interacting with Cell Wall Pectins

PubMed Central

Fang, Jing; Tao, Lin; Shen, Ren Fang; Li, Ya Lin; Xiao, Hong Dong; Feng, Ying Ming; Wen, Hai Xiang; Guan, Jia Hua; Wu, Li Shu; He, Yong Ming; Goldbach, Heiner E.; Yu, Min

2017-01-01

Aluminum (Al) toxicity is the primary factor limiting crop growth in acidic soils. Boron (B) alleviates Al toxicity in plants, which is mainly considered to be due to the formation of Rhamnogalacturonan II-B (RGII-B) complexes, which helps to stabilize the cytoskeleton. It is unclear yet whether this is due to the increasing of net negative charges and/or further mechanisms. Kinetics of Al accumulation and adsorption were investigated using entire cells, cell wall and pectin of root border cells (RBCs) of pea (Pisum sativum), to reveal the mechanism of B in interacting with alkali-soluble and chelator-soluble pectin for an increased Al tolerance in RBCs. The results show that B could rescue RBCs from Al-induced cell death by accumulating more Al in the cell wall, predominately in alkali-soluble pectin. Boron also promotes Al3+ adsorption and inhibits Al3+ desorption from alkali-soluble pectin. Thus, more Al3+ is immobilized within the alkali-soluble pectin fraction and less in the chelator-soluble pectin, rendering Al3+ less mobile. Boron induces an increase of RG-II (KDO,2-keto-3-deoxyoctonic acid) content for forming more borate-RGII complexes, and the decrease of pectin methyl-esterification, thus creates more negative charges to immobilize Al3+ in cell wall pectin. The study provides evidence that abundant B supply enhances the immobilization of Al in alkali-soluble pectin, thus most likely reducing the entry of Al3+ into the symplast from the surroundings. PMID:28533794

Rapid transcriptome characterization and parsing of sequences in a non-model host-pathogen interaction; pea-Sclerotinia sclerotiorum

PubMed Central

2012-01-01

Background White mold, caused by Sclerotinia sclerotiorum, is one of the most important diseases of pea (Pisum sativum L.), however, little is known about the genetics and biochemistry of this interaction. Identification of genes underlying resistance in the host or pathogenicity and virulence factors in the pathogen will increase our knowledge of the pea-S. sclerotiorum interaction and facilitate the introgression of new resistance genes into commercial pea varieties. Although the S. sclerotiorum genome sequence is available, no pea genome is available, due in part to its large genome size (~3500 Mb) and extensive repeated motifs. Here we present an EST data set specific to the interaction between S. sclerotiorum and pea, and a method to distinguish pathogen and host sequences without a species-specific reference genome. Results 10,158 contigs were obtained by de novo assembly of 128,720 high-quality reads generated by 454 pyrosequencing of the pea-S. sclerotiorum interactome. A method based on the tBLASTx program was modified to distinguish pea and S. sclerotiorum ESTs. To test this strategy, a mixture of known ESTs (18,490 pea and 17,198 S. sclerotiorum ESTs) from public databases were pooled and parsed; the tBLASTx method successfully separated 90.1% of the artificial EST mix with 99.9% accuracy. The tBLASTx method successfully parsed 89.4% of the 454-derived EST contigs, as validated by PCR, into pea (6,299 contigs) and S. sclerotiorum (2,780 contigs) categories. Two thousand eight hundred and forty pea ESTs and 996 S. sclerotiorum ESTs were predicted to be expressed specifically during the pea-S. sclerotiorum interaction as determined by homology search against 81,449 pea ESTs (from flowers, leaves, cotyledons, epi- and hypocotyl, and etiolated and light treated etiolated seedlings) and 57,751 S. sclerotiorum ESTs (from mycelia at neutral pH, developing apothecia and developing sclerotia). Among those ESTs specifically expressed, 277 (9.8%) pea ESTs were predicted to be involved in plant defense and response to biotic or abiotic stress, and 93 (9.3%) S. sclerotiorum ESTs were predicted to be involved in pathogenicity/virulence. Additionally, 142 S. sclerotiorum ESTs were identified as secretory/signal peptides of which only 21 were previously reported. Conclusions We present and characterize an EST resource specific to the pea-S. sclerotiorum interaction. Additionally, the tBLASTx method used to parse S. sclerotiorum and pea ESTs was demonstrated to be a reliable and accurate method to distinguish ESTs without a reference genome. PMID:23181755

Biological effects of weightlessness and clinostatic conditions registered in cells of root meristem and cap of higher plants

NASA Astrophysics Data System (ADS)

Sytnik, K. M.; Kordyum, E. L.; Belyavskaya, N. A.; Nedukha, E. M.; Tarasenko, V. A.

Research in cellular reproduction, differentiation and vital activity, i.e. processes underlying the development and functioning of organisms, plants included, is essential for solving fundamental and applied problems of space biology. Detailed anatomical analysis of roots of higher plants grown on board the Salyut 6 orbital research station show that under conditions of weightlessness for defined duration mitosis, cytokinesis and tissue differentiation in plant vegetative organs occur essentially normally. At the same time, certain rearrangements in the structural organization of cellular organelles - mainly the plastid apparatus, mitochondria, Golgi apparatus and nucleus - are established in the root meristem and cap of the experimental plants. This is evidence for considerable changes in cellular metabolism. The structural changes in the subcellular level arising under spaceflight conditions are partially absent in clinostat experiments designed to simulate weightlessness. Various clinostatic conditions have different influences on the cell structural and functional organization than does space flight. It is suggested that alterations of cellular metabolism under weightlessness and clinostatic conditions occur within existing genetic programs.

Mevalonate-derived quinonemethide triterpenoid from in vitro roots of Peritassa laevigata and their localization in root tissue by MALDI imaging

NASA Astrophysics Data System (ADS)

Pina, Edieidia S.; Silva, Denise B.; Teixeira, Simone P.; Coppede, Juliana S.; Furlan, Maysa; França, Suzelei C.; Lopes, Norberto P.; Pereira, Ana Maria S.; Lopes, Adriana A.

2016-03-01

Biosynthetic investigation of quinonemethide triterpenoid 22β-hydroxy-maytenin (2) from in vitro root cultures of Peritassa laevigata (Celastraceae) was conducted using 13C-precursor. The mevalonate pathway in P. laevigata is responsible for the synthesis of the quinonemethide triterpenoid scaffold. Moreover, anatomical analysis of P. laevigata roots cultured in vitro and in situ showed the presence of 22β-hydroxy-maytenin (2) and maytenin (1) in the tissues from transverse or longitudinal sections with an intense orange color. MALDI-MS imaging confirmed the distribution of (2) and (1) in the more distal portions of the root cap, the outer cell layers, and near the vascular cylinder of P. laevigata in vitro roots suggesting a role in plant defense against infection by microorganisms as well as in the root exudation processes.

Salt: Too Much of a Good Thing | NIH MedlinePlus the Magazine

MedlinePlus

... 1 cup of raw peas has 4 mg sodium. Answer Canned peas have three times more sodium than frozen peas. Canned Peas Caption: Canned Peas, ... 0%, Saturated Fat 0g 0%, Cholesterol 0mg 0%, Sodium 380 mg 16%, Total Carbohydrate 12g 4%, Dietary ...

Immunofluorescence detection of pea protein in meat products.

PubMed

Petrášová, Michaela; Pospiech, Matej; Tremlová, Bohuslava; Javůrková, Zdeňka

2016-08-01

In this study we developed an immunofluorescence method to detect pea protein in meat products. Pea protein has a high nutritional value but in sensitive individuals it may be responsible for causing allergic reactions. We produced model meat products with various additions of pea protein and flour; the detection limit (LOD) of the method for pea flour was 0.5% addition, and for pea protein it was 0.001% addition. The repeatabilities and reproducibilities for samples both positive and negative for pea protein were all 100%. In a blind test with model products and commercial samples, there was no statistically significant difference (p > 0.05) between the declared concentrations of pea protein and flour and the immunofluorescence method results. Sensitivity was 1.06 and specificity was 1.00. These results show that the immunofluorescence method is suitable for the detection of pea protein in meat products.

Neuropharmacological and neurochemical properties of N-(2-cyanoethyl)-2-phenylethylamine, a prodrug of 2-phenylethylamine.

PubMed Central

Baker, G. B.; Coutts, R. T.; Rao, T. S.

1987-01-01

1 N-(2-cyanoethyl)-2-phenylethylamine (CEPEA) was examined as a possible prodrug of 2-phenylethylamine (PEA). 2 Pharmacokinetics of PEA and CEPEA were investigated in rat brain, blood and liver by gas chromatography with electron-capture detection (GC-ECD). Interactions of PEA and CEPEA with putative neurotransmitter amines were investigated by use of high performance liquid chromatography with electrochemical detection (h.p.l.c.-e.c.). 3 Administration of PEA caused transient increases in PEA concentrations which decreased rapidly in brain and blood and at a slower rate in liver. Administration of CEPEA caused sustained elevations of PEA concentrations and elimination of PEA was markedly decreased in these tissues relative to the situation after administration of PEA itself. 4 Administration of CEPEA caused more prolonged decreases in brain noradrenaline, dopamine and 5-hydroxytryptamine concentrations than those observed after PEA administration, although values increased to control levels eventually. PMID:2890391

Effects of ionizing radiation on sensorial, chemical, and microbiological quality of frozen corn and peas.

PubMed

Fan, Xuetong; Sokorai, Kimberly J B

2007-08-01

The effects of irradiation (0, 1.8, and 4.5 kGy) on the quality of frozen corn and peas were investigated during a 12month period of postirradiation storage at -18 degrees C. Irradiation of frozen corn and peas caused a reduction in ascorbic acid content of both vegetables and a loss of texture in peas but had no significant effects on instrumental color parameters (L*, a*, and b*), carotenoid and chlorophyll content, or antioxidant capacity of corn and peas. Irradiation reduced microbial loads of frozen peas and increased display life at 23 degrees C of thawed peas by preserving the green color, apparently because of slower increases in the population of acid-producing microorganisms in the irradiated samples. Overall, irradiation significantly reduced the microbial load and increased the display life of peas and had minimal detrimental effects on the quality of frozen corn and peas.

CAP waveform estimation from the measured electrical bioimpedance values: Patient's heart rate variability analysis.

PubMed

Krivoshei, A; Uuetoa, H; Min, M; Annus, P; Uuetoa, T; Lamp, J

2015-08-01

The paper presents analysis of the generic transfer function (TF) between Electrical Bioimpedance (EBI) measured non-invasively on the wrist and Central Aortic Pressure (CAP) invasively measured at the aortic root. Influence of the Heart Rate (HR) variations on the generic TF and on reconstructed CAP waveforms is investigated. The HR variation analysis is provided on a single patient data to exclude inter-patient influences at the current research stage. A new approach for the generic TF estimating from a data ensemble is presented as well. Moreover, an influence of the cardiac period beginning point selection is analyzed and empirically optimal solution for its selection is proposed.

The effects of fermentation and enzymatic treatment of pea on nutrient digestibility and growth performance of broilers.

PubMed

Goodarzi Boroojeni, F; Senz, M; Kozłowski, K; Boros, D; Wisniewska, M; Rose, D; Männer, K; Zentek, J

2017-10-01

The present study examined the impacts of native, fermented or enzymatically treated peas (Pisum sativum L.) inclusion in broiler diets, on growth performance and nutrient digestibility. For the fermentation process, Madonna pea was mixed with water (1/1) containing 2.57×108 Bacillus subtilis (GalliPro®) spores/kg pea and then, incubated for 48 h at 30 °C. For the enzymatic treatment process, the used water for dough production contained three enzymes, AlphaGalTM (α-galactosidase), RONOZYME® ProAct and VP (protease and pectinases respectively - DSM, Switzerland) and the pea dough incubated for 24 h at 30°C. Nine corn-wheat-soybean diets were formulated by supplying 10%, 20% and 30% of the required CP with either native, fermented or enzymatically treated peas. Performance was recorded weekly and at the end of the experiment (day 35), apparent ileal digestibility (AID) of CP, amino acids (AA), crude fat, starch, Ca, P and K were determined. Data were subjected to ANOVA using GLM procedure with a 3×3 factorial arrangement of treatments. Both processes reduced α-galactosides, phytate, trypsin inhibitor activity and resistant starch in peas. Increasing levels of pea products up to 300 g/kg diet, reduced BW gain and feed intake (P⩽0.05). Broilers fed diets containing enzymatically treated pea had the best feed conversion ratio at day 35. Different types of pea product and their inclusion levels had no effect on AID of all nutrients. The interaction between type of the pea products and inclusion levels was significant for AID of starch. For native pea diets, 10% group showed similar AID of starch to 20% native pea but it had higher AID than 30% native pea. For fermented and enzymatically treated groups, all three levels displayed similar AID of starch. In conclusion, enzymatic treatment and fermentation could improve the nutritional quality of pea. Inclusion of enzymatically treated pea in broiler diets could improve broiler performance compared with other pea products while, it displayed neither positive nor negative impact on nutrient digestibility. The present findings indicate the feasibility of these processes, particularly enzymatic treatment, for improving the nutritional quality of pea as a protein source for broiler nutrition.

Review of the health benefits of peas (Pisum sativum L.).

PubMed

Dahl, Wendy J; Foster, Lauren M; Tyler, Robert T

2012-08-01

Pulses, including peas, have long been important components of the human diet due to their content of starch, protein and other nutrients. More recently, the health benefits other than nutrition associated with pulse consumption have attracted much interest. The focus of the present review paper is the demonstrated and potential health benefits associated with the consumption of peas, Pisum sativum L., specifically green and yellow cotyledon dry peas, also known as smooth peas or field peas. These health benefits derive mainly from the concentration and properties of starch, protein, fibre, vitamins, minerals and phytochemicals in peas. Fibre from the seed coat and the cell walls of the cotyledon contributes to gastrointestinal function and health, and reduces the digestibility of starch in peas. The intermediate amylose content of pea starch also contributes to its lower glycaemic index and reduced starch digestibility. Pea protein, when hydrolysed, may yield peptides with bioactivities, including angiotensin I-converting enzyme inhibitor activity and antioxidant activity. The vitamin and mineral contents of peas may play important roles in the prevention of deficiency-related diseases, specifically those related to deficiencies of Se or folate. Peas contain a variety of phytochemicals once thought of only as antinutritive factors. These include polyphenolics, in coloured seed coat types in particular, which may have antioxidant and anticarcinogenic activity, saponins which may exhibit hypocholesterolaemic and anticarcinogenic activity, and galactose oligosaccharides which may exert beneficial prebiotic effects in the large intestine.

Effect of roasted pea flour/starch and encapsulated pea starch incorporation on the in vitro starch digestibility of pea breads.

PubMed

Lu, Zhan-Hui; Donner, Elizabeth; Liu, Qiang

2018-04-15

Oven or microwave roasting and alginate encapsulation of pea flour and starch to produce novel pea ingredients for enrichment of slowly digestible starch (SDS) and resistant starch (RS) content in pea bread were investigated. Pea flour treated either by oven roasting (160°C, 30min) or by microwave roasting (1.1kW, 6min) effectively retained its low starch digestibility similar to its native form (∼25% SDS; ∼60% RS). When oven roasting was applied to pea starch, SDS content increased triply compared to the fully boiled counterpart. Alginate encapsulation effectively controlled carbohydrate release to simulated gastric, intestinal and colonic fluids, and thus largely enriched the SDS and RS fractions in starch. Pea bread containing up to 37.5% of encapsulated roasted MPS pea starch not only provided high SDS and RS fractions (23.9% SDS and 30.2% RS) compared to a white bread control (0.2% SDS and 2.5% RS), but also provided an acceptable palatability. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Monitoring 2-phenylethanamine and 2-(3-hydroxyphenyl)acetamide sulfate in doping controls.

PubMed

Sigmund, Gerd; Dib, Josef; Tretzel, Laura; Piper, Thomas; Bosse, Christina; Schänzer, Wilhelm; Thevis, Mario

2015-01-01

2-Phenylethanamine (phenethylamine, PEA) represents the core structure of numerous drugs with stimulant-like properties and is explicitly featured as so-called specified substance on the World Anti-Doping Agency (WADA) Prohibited List. Due to its natural occurrence in humans as well as its presence in dietary products, studies concerning the ability of test methods to differentiate between an illicit intake and the renal elimination of endogenously produced PEA were indicated. Following the addition of PEA to the Prohibited List in January 2015, retrospective evaluation of routine doping control data of 10 190 urine samples generated by combined gas chromatography-mass spectrometry and nitrogen phosphorus-specific detection (GC-MS/NPD) was performed. Signals for PEA at approximate concentrations > 500 ng/mL were observed in 31 cases (0.3%), which were subjected to a validated isotope-dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) test method for accurate quantification of the target analyte. Further, using elimination study urine samples collected after a single oral administration of 250 mg of PEA hydrochloride to two healthy male volunteers, two tentatively identified metabolites of PEA were observed and evaluated concerning their utility as discriminative markers for PEA intake. The ID-LC-MS/MS approach was extended to allow for the simultaneous detection of PEA and 2-(3-hydroxyphenyl)acetamide sulfate (M1), and concentration ratios of M1 and PEA were calculated for elimination study urine samples and a total of 205 doping control urine samples that returned findings for PEA at estimated concentrations of 50-2500 ng/mL. Urine samples of the elimination study with PEA yielded concentration ratios of M1/PEA up to values of 9.4. Notably, the urinary concentration of PEA did increase with the intake of PEA only to a modest extent, suggesting a comprehensive metabolism of the orally administered substance. Conversely, doping control urine samples with elevated (>50 ng/mL) amounts of PEA returned quantifiable concentrations of M1 only in 3 cases, which yielded maximum ratios of M1/PEA of 0.9, indicating an origin of PEA other than an orally ingested drug formulation. Consequently, the consideration of analyte abundance ratios (e.g. M1/PEA) is suggested as a means to identify the use of PEA by athletes, but further studies to support potential decisive criteria are warranted. Copyright © 2015 John Wiley & Sons, Ltd.

Numerical study on the influence of boss cap fins on efficiency of controllable-pitch propeller

NASA Astrophysics Data System (ADS)

Xiong, Ying; Wang, Zhanzhi; Qi, Wanjiang

2013-03-01

Numerical simulation is investigated to disclose how propeller boss cap fins (PBCF) operate utilizing Reynolds-averaged Navier-Stokes (RANS) method. In addition, exploration of the influencing mechanism of PBCF on the open water efficiency of one controllable-pitch propeller is analyzed through the open water characteristic curves, blade surface pressure distribution and hub streamline distribution. On this basis, the influence of parameters including airfoil profile, diameter, axial position of installation and circumferential installation angle on the open water efficiency of the controllable-pitch propeller is investigated. Numerical results show: for the controllable-pitch propeller, the thrust generated is at the optimum when the radius of boss cap fins is 1.5 times of propeller hub with an optimal installation position in the axial direction, and its optimal circumferential installation position is the midpoint of the extension line of the front and back ends of two adjacent propeller roots in the front of fin root. Under these optimal parameters, the gain of open water efficiency of the controllable-pitch propeller with different advance velocity coefficients is greater than 0.01, which accounts for approximately an increase of 1%-5% of open water efficiency.

PED/PEA-15 inhibits hydrogen peroxide-induced apoptosis in Ins-1E pancreatic beta-cells via PLD-1.

PubMed

Fiory, Francesca; Parrillo, Luca; Raciti, Gregory Alexander; Zatterale, Federica; Nigro, Cecilia; Mirra, Paola; Falco, Roberta; Ulianich, Luca; Di Jeso, Bruno; Formisano, Pietro; Miele, Claudia; Beguinot, Francesco

2014-01-01

The small scaffold protein PED/PEA-15 is involved in several different physiologic and pathologic processes, such as cell proliferation and survival, diabetes and cancer. PED/PEA-15 exerts an anti-apoptotic function due to its ability to interfere with both extrinsic and intrinsic apoptotic pathways in different cell types. Recent evidence shows that mice overexpressing PED/PEA-15 present larger pancreatic islets and increased beta-cells mass. In the present work we investigated PED/PEA-15 role in hydrogen peroxide-induced apoptosis in Ins-1E beta-cells. In pancreatic islets isolated from Tg(PED/PEA-15) mice hydrogen peroxide-induced DNA fragmentation was lower compared to WT islets. TUNEL analysis showed that PED/PEA-15 overexpression increases the viability of Ins-1E beta-cells and enhances their resistance to apoptosis induced by hydrogen peroxide exposure. The activity of caspase-3 and the cleavage of PARP-1 were markedly reduced in Ins-1E cells overexpressing PED/PEA-15 (Ins-1E(PED/PEA-15)). In parallel, we observed a decrease of the mRNA levels of pro-apoptotic genes Bcl-xS and Bad. In contrast, the expression of the anti-apoptotic gene Bcl-xL was enhanced. Accordingly, DNA fragmentation was higher in control cells compared to Ins-1E(PED/PEA-15) cells. Interestingly, the preincubation with propranolol, an inhibitor of the pathway of PLD-1, a known interactor of PED/PEA-15, responsible for its deleterious effects on glucose tolerance, abolishes the antiapoptotic effects of PED/PEA-15 overexpression in Ins-1E beta-cells. The same results have been obtained by inhibiting PED/PEA-15 interaction with PLD-1 in Ins-1E(PED/PEA-15). These results show that PED/PEA-15 overexpression is sufficient to block hydrogen peroxide-induced apoptosis in Ins-1E cells through a PLD-1 mediated mechanism.

Design and implementation of the protective cap/biobarrier experiment at the Idaho National Engineering Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Limbach, W.E.; Ratzlaff, T.D.; Anderson, J.E.

1994-12-31

The Protective Cap/Biobarrier Experiment (PCBE), initiated in 1993 at the Idaho National Engineering Laboratory (INEL), is a strip-split plot experiment with three replications designed to rigorously test a 2.0-m loessal soil cap against a cap recommended by the US Environmental Protection Agency and two caps with biological intrusion barriers. Past research at INEL indicates that it should be possible to exclude water from buried wastes using natural materials and natural processes in arid environments rather than expensive materials (geotextiles) and highly engineered caps. The PCBE will also test the effects of two vegetal covers and three irrigation levels on capmore » performance. Drainage pans, located at the bottom of each plot, will monitor cap failure. Soil water profiles will be monitored biweekly by neutron probe and continuously by time domain reflectometry. The performance of each cap design will be monitored under a variety of conditions through 1998. From 1994 to 1996, the authors will assess plant establishment, rooting depths, patterns of moisture extraction and their interactions among caps, vegetal covers, and irrigation levels. In 1996, they will introduce ants and burrowing mammals to test the structural integrity of each cap design. In 1998, the authors will apply sufficient water to determine the failure limit for each cap design. The PCBE should provide reliable knowledge of the performances of the four cap designs under a variety of conditions and aid in making hazardous-waste management decisions at INEL and at disposal sites in similar environments.« less

Root elongation against a constant force: experiment with a computerized feedback-controlled device

NASA Technical Reports Server (NTRS)

Kuzeja, P. S.; Lintilhac, P. M.; Wei, C.

2001-01-01

Axial force was applied to the root tip of corn (Zea mays L. cv. Merit) seedlings using a computerized, feedback-controlled mechanical device. The system's feedback capability allowed continuous control of a constant tip load, and the attached displacement transducer provided the time course of root elongation. Loads up to 7.5 g decreased the root elongation rate by 0.13 mm h-1 g-1, but loads 7.5 to 17.5 g decreased the growth rate by only 0.04 mm h-1 g-1. Loads higher than 18 g stopped root elongation completely. Measurement of the cross-sectional areas of the root tips indicated that the 18 g load had applied about 0.98 MPa of axial pressure to the root, thereby exceeding the root's ability to respond with increased turgor pressure. Recorded time-lapse images of loaded roots showed that radial thickening (swelling) occurred behind the root cap, whose cross-sectional area increased with tip load.

2-Pentadecyl-2-Oxazoline, the Oxazoline of Pea, Modulates Carrageenan-Induced Acute Inflammation

PubMed Central

Petrosino, Stefania; Campolo, Michela; Impellizzeri, Daniela; Paterniti, Irene; Allarà, Marco; Gugliandolo, Enrico; D’Amico, Ramona; Siracusa, Rosalba; Cordaro, Marika; Esposito, Emanuela; Di Marzo, Vincenzo; Cuzzocrea, Salvatore

2017-01-01

N-acylethanolamines (NAEs) involve a family of lipid molecules existent in animal and plant, with N-palmitoylethanolamide (PEA) that arouses great attention owing to its anti-inflammatory, analgesic and neuroprotective activities. Because PEA is produced on demand and exerts pleiotropic effects, the modulation of specific amidases for NAEs (and in particular NAE-hydrolyzing acid amidase NAAA, which is more selective for PEA) could be a condition to preserve its levels. Here we investigate the effect of 2-Pentadecyl-2-oxazoline (PEA-OXA) the oxazoline of PEA, on human recombinant NAAA in vitro and in an established model of Carrageenan (CAR)-induced rat paw inflammation. PEA-OXA dose-dependently significantly inhibited recombinant NAAA and, orally administered to rats (10 mg/kg), limiting histological damage, thermal hyperalgesia and the increase of infiltrating inflammatory cells after CAR injection in the rat right hindpaw, compared to ultramicronized PEA given orally at the same dose (10 mg/kg). These effects were accompanied by elevation of paw PEA levels. Moreover, PEA-OXA markedly reduced neutrophil infiltration and pro-inflammatory cytokine release and prevented CAR-induced IκB-α degradation, nuclear translocation of NF-κB p65, the increase of inducible nitric oxide synthase, cyclooxygenase-2, intercellular adhesion molecule-1, and mast cell activation. Experiments in PPAR-α knockout mice showed that the anti-inflammatory effects of PEA-OXA were not dependent on the presence of PPAR-α receptors. In conclusion, NAAA modulators as PEA-OXA could help to maximize the tissue availability of PEA by increasing its levels and anti-inflammatory effects. PMID:28611664

Cross-reactivity of a new food ingredient, dun pea, with legumes, and risk of anaphylaxis in legume allergic children.

PubMed

Richard, C; Jacquenet, S; Sergeant, P; Moneret-Vautrin, D A

2015-07-01

Legume allergy is the fifth food allergy in Europe. The dun pea (Pisum sativum sativum var. arvense), a pea belonging to the same subspecies as green pea, has been recently introduced as an ingredient in the human food industry. The aims of this study were to evaluate the cross-reactivity between dun pea and other legumes and to search for modification of allergenicity induced by food technologies. A series of 36 patients with legume and/or peanut allergy was studied. They underwent skin tests to peanut and a panel of legumes including dun pea. Specific IgE to dun pea and cross-reactivity to peanut allergens, particularly to Ara h 1, were evaluated by ELISA. Proteins and allergens of different pea extracts were studied by SDS-PAGE and immunoblots. In France and Belgium, 7.7% of severe food anaphylaxis cases were due to legumes. Patients with isolated legume allergy had positive prick tests to dun pea, whereas patients with isolated peanut allergy had negative prick tests. Cross-reactivity between sIgE to peanut and dun pea was observed, and more frequently than expected (96%) peanut-allergic patients with legume sensitization or allergy had sIgE to Ara h 1. Analysis of dun pea allergens suggested that protein epitopes were presented differently in dun pea seeds, isolate and flour. This study identifies, for the first time, a risk of dun pea allergy in legume-allergic patients and in a subset of peanut-allergic patients.

7 CFR 868.101 - General information.

Code of Federal Regulations, 2013 CFR

2013-01-01

... for Beans, Whole Dry Peas, Split Peas, and Lentils, which provide a uniform language for describing..., suspending, or terminating the U.S. standards for Beans, Whole Dry Peas, Split Peas, and Lentils...

7 CFR 868.101 - General information.

Code of Federal Regulations, 2012 CFR

2012-01-01

... for Beans, Whole Dry Peas, Split Peas, and Lentils, which provide a uniform language for describing..., suspending, or terminating the U.S. standards for Beans, Whole Dry Peas, Split Peas, and Lentils...

7 CFR 868.101 - General information.

Code of Federal Regulations, 2014 CFR

2014-01-01

... for Beans, Whole Dry Peas, Split Peas, and Lentils, which provide a uniform language for describing..., suspending, or terminating the U.S. standards for Beans, Whole Dry Peas, Split Peas, and Lentils...

7 CFR 868.101 - General information.

Code of Federal Regulations, 2011 CFR

2011-01-01

... for Beans, Whole Dry Peas, Split Peas, and Lentils, which provide a uniform language for describing..., suspending, or terminating the U.S. standards for Beans, Whole Dry Peas, Split Peas, and Lentils...

7 CFR 868.101 - General information.

Code of Federal Regulations, 2010 CFR

2010-01-01

... for Beans, Whole Dry Peas, Split Peas, and Lentils, which provide a uniform language for describing..., suspending, or terminating the U.S. standards for Beans, Whole Dry Peas, Split Peas, and Lentils...

An Overview of the Current Status of Southernpea Breeding Programs in the United States

USDA-ARS?s Scientific Manuscript database

American Horticulturists use the term southernpea when referring to any type of cowpea being grown as a vegetable crop. Several types of southernpeas, e.g., pinkeye peas, blackeye peas, crowder peas, cream peas and snap peas, have a long history of use in the southern United States. An extensive i...

CELL POPULATION KINETICS OF EXCISED ROOTS OF PISUM SATIVUM

PubMed Central

Van't Hof, Jack

1965-01-01

The cell population kinetics of excised, cultured pea roots was studied with the use of tritiated thymidine and colchicine to determine (1) the influence of excision, (2) the influence of sucrose concentration, (3) the average mitotic cycle duration, and (4) the duration of mitosis and the G 1, S, and G 2 periods of interphase.1 The results indicate that the process of excision causes a drop in the frequency of mitotic figures when performed either at the beginning of the culture period or after 100 hours in culture. This initial decrease in frequency of cell division is independent of sucrose concentration, but the subsequent rise in frequency of division, after 12 hours in culture, is dependent upon sucrose concentration. Two per cent sucrose maintains the shortest mitotic cycle duration. The use of colchicine indicated an average cycle duration of 20 hours, whereas the use of tritiated thymidine produced an average cycle duration of 17 hours. PMID:5857253

Absence of Hg transpiration by shoot after Hg uptake by roots of six terrestrial plant species.

PubMed

Greger, Maria; Wang, Yaodong; Neuschütz, Clara

2005-03-01

In this paper we investigated if, and to what extent, six different plant species accumulate, translocate and emit mercury (Hg) into the air. The Hg uptake by roots, distribution of Hg to the shoot and release of Hg via shoots of garden pea, spring wheat, sugar beet, oil-seed rape, white clover and willow were investigated in a transpiration chamber. The airborne Hg was trapped in a Hopcalite trap or a gold trap. Traps and plant materials were analysed for content of Hg by CVAAS. The results show that all plant species were able to take up Hg to a large extent from a nutrient solution containing 200 microg L(-1) Hg. However, the Hg translocation to the shoot was low (0.17-2.5%) and the Hg that reached the leaves was trapped and no release of the absorbed Hg to the air was detected.

Molecular and morphological surface analysis: effect of filling pastes and cleaning agents on root dentin.

PubMed

Dainezi, Vanessa Benetello; Iwamoto, Alexsandra Shizue; Martin, Airton Abrahão; Soares, Luís Eduardo Silva; Hosoya, Yumiko; Pascon, Fernanda Miori; Puppin-Rontani, Regina Maria

2017-01-01

This study evaluated the effect of different filling pastes and cleaning agents on the root dentin of primary teeth using Fourier-transformed Raman spectroscopy (FT-Raman), micro energy-dispersive X-ray fluorescence (µ-EDXRF) and scanning electron microscopic (SEM) analysis. Eighty roots of primary teeth were endodontically prepared and distributed into 4 groups and filled according to the following filling pastes: Control-no filling (CP), Calen®+zinc oxide (CZ), Calcipex II® (CII), Vitapex® (V). After seven days, filling paste groups were distributed to 4 subgroups according to cleaning agents (n=5): Control-no cleaning (C), Ethanol (E), Tergenform® (T), 35% Phosphoric acid (PA). Then, the roots were sectioned and the dentin root sections were internally evaluated by FT-Raman, µ-EDXRF and SEM. Data was submitted to two-way ANOVA and Tukey tests (α=0.05). Regarding filling pastes, there was no significant difference in organic content. CP provided the lowest calcium values and, calcium/phosphoric ratio (Ca/P), and the highest phosphoric values. For cleaning agents there was no difference in organic content when compared to the C; however, T showed significantly higher calcium and Ca/P than PA. All groups showed similar results for phosphorus. The dentin smear layer was present after use of the cleaning agents, except PA. The filling pastes changed the inorganic content, however they did not change the organic content. Cleaning agents did not alter the inorganic and organic content. PA cleaned and opened dentin tubules.

A Role for the TOC Complex in Arabidopsis Root Gravitropism1[W][OA

PubMed Central

Stanga, John P.; Boonsirichai, Kanokporn; Sedbrook, John C.; Otegui, Marisa S.; Masson, Patrick H.

2009-01-01

Arabidopsis (Arabidopsis thaliana) roots perceive gravity and reorient their growth accordingly. Starch-dense amyloplasts within the columella cells of the root cap are important for gravitropism, and starchless mutants such as pgm1 display an attenuated response to gravistimulation. The altered response to gravity1 (arg1) mutant is known to be involved with the early phases of gravity signal transduction. arg1 responds slowly to gravistimulation and is in a genetically distinct pathway from pgm1, as pgm1 mutants enhance the gravitropic defect of arg1. arg1 seeds were mutagenized with ethylmethane sulfonate to identify new mutants that enhance the gravitropic defect of arg1. Two modifier of arg1 mutants (mar1 and mar2) grow in random directions only when arg1 is present, do not affect phototropism, and respond like the wild type to application of phytohormones. Both have mutations affecting different components of the Translocon of Outer Membrane of Chloroplasts (TOC) complex. mar1 possesses a mutation in the TOC75-III gene; mar2 possesses a mutation in the TOC132 gene. Overexpression of TOC132 rescues the random growth phenotype of mar2 arg1 roots. Root cap amyloplasts in mar2 arg1 appear ultrastructurally normal. They saltate like the wild type and sediment at wild-type rates upon gravistimulation. These data point to a role for the plastidic TOC complex in gravity signal transduction within the statocytes. PMID:19211693

A role for the TOC complex in Arabidopsis root gravitropism.

PubMed

Stanga, John P; Boonsirichai, Kanokporn; Sedbrook, John C; Otegui, Marisa S; Masson, Patrick H

2009-04-01

Arabidopsis (Arabidopsis thaliana) roots perceive gravity and reorient their growth accordingly. Starch-dense amyloplasts within the columella cells of the root cap are important for gravitropism, and starchless mutants such as pgm1 display an attenuated response to gravistimulation. The altered response to gravity1 (arg1) mutant is known to be involved with the early phases of gravity signal transduction. arg1 responds slowly to gravistimulation and is in a genetically distinct pathway from pgm1, as pgm1 mutants enhance the gravitropic defect of arg1. arg1 seeds were mutagenized with ethylmethane sulfonate to identify new mutants that enhance the gravitropic defect of arg1. Two modifier of arg1 mutants (mar1 and mar2) grow in random directions only when arg1 is present, do not affect phototropism, and respond like the wild type to application of phytohormones. Both have mutations affecting different components of the Translocon of Outer Membrane of Chloroplasts (TOC) complex. mar1 possesses a mutation in the TOC75-III gene; mar2 possesses a mutation in the TOC132 gene. Overexpression of TOC132 rescues the random growth phenotype of mar2 arg1 roots. Root cap amyloplasts in mar2 arg1 appear ultrastructurally normal. They saltate like the wild type and sediment at wild-type rates upon gravistimulation. These data point to a role for the plastidic TOC complex in gravity signal transduction within the statocytes.

Mevalonate-derived quinonemethide triterpenoid from in vitro roots of Peritassa laevigata and their localization in root tissue by MALDI imaging

PubMed Central

Pina, Edieidia S.; Silva, Denise B.; Teixeira, Simone P.; Coppede, Juliana S.; Furlan, Maysa; França, Suzelei C.; Lopes, Norberto P.; Pereira, Ana Maria S.; Lopes, Adriana A.

2016-01-01

Biosynthetic investigation of quinonemethide triterpenoid 22β-hydroxy-maytenin (2) from in vitro root cultures of Peritassa laevigata (Celastraceae) was conducted using 13C-precursor. The mevalonate pathway in P. laevigata is responsible for the synthesis of the quinonemethide triterpenoid scaffold. Moreover, anatomical analysis of P. laevigata roots cultured in vitro and in situ showed the presence of 22β-hydroxy-maytenin (2) and maytenin (1) in the tissues from transverse or longitudinal sections with an intense orange color. MALDI-MS imaging confirmed the distribution of (2) and (1) in the more distal portions of the root cap, the outer cell layers, and near the vascular cylinder of P. laevigata in vitro roots suggesting a role in plant defense against infection by microorganisms as well as in the root exudation processes. PMID:26943243

The presence of orellanine in spores and basidiocarp from Cortinarius orellanus and Cortinarius rubellus.

PubMed

Koller, Gry Eb; Høiland, Klaus; Janak, Karel; Størmer, Fredrik C

2002-01-01

This is the first report quantifying the orellanine content in basidiospores. The toxin content and tissue distribution of orellanine were determined from Cortinarius orellanus (Fr.) Fr. and Cortinarius rubellus Cooke. Basidiospores, the basidiocarp, divided into cap and stem, and mycorrhiza roots were analyzed to determine the amount of orellanine by reversed phase high performance liquid chromatography and thin layer chromatography. The orellanine contents in spores were 0.31% (C. orellanus) and 0.09% (C. rubellus). In caps, we found the toxin content to be 0.94% (C. orellanus) and 0.78% (C. rubellus), in stems 0.48% (C. orellanus) and 0.42% (C. rubellus) and in mycorrhiza roots from C. rubellus we determined the orellanine contents to 0.03%. In addition, extracts from the different structures of the basidiocarp of C. orellanus and C. rubellus, with an orellanine content corresponding to 25 nmol, inhibited the growth of Bacillus subtilis.

Effect of Processing on the in Vitro and in Vivo Protein Quality of Yellow and Green Split Peas (Pisum sativum).

PubMed

Nosworthy, Matthew G; Franczyk, Adam J; Medina, Gerardo; Neufeld, Jason; Appah, Paulyn; Utioh, Alphonsus; Frohlich, Peter; House, James D

2017-09-06

In order to determine the effect of extrusion, baking, and cooking on the protein quality of yellow and green split peas, a rodent bioassay was conducted and compared to an in vitro method of protein quality determination. The Protein Digestibility-Corrected Amino Acid Score (PDCAAS) of green split peas (71.4%) was higher than that of yellow split peas (67.8%), on average. Similarly, the average Digestible Indispensable Amino Acid Score (DIAAS) of green split peas (69%) was higher than that of yellow split peas (67%). Cooked green pea flour had lower PDCAAS and DIAAS values (69.19% and 67%) than either extruded (73.61%, 70%) or baked (75.22%, 70%). Conversely, cooked yellow split peas had the highest PDCCAS value (69.19%), while extruded yellow split peas had the highest DIAAS value (67%). Interestingly, a strong correlation was found between in vivo and in vitro analysis of protein quality (R 2 = 0.9745). This work highlights the differences between processing methods on pea protein quality and suggests that in vitro measurements of protein digestibility could be used as a surrogate for in vivo analysis.

Acute effects of pea protein and hull fibre alone and combined on blood glucose, appetite, and food intake in healthy young men--a randomized crossover trial.

PubMed

Mollard, Rebecca C; Luhovyy, Bohdan L; Smith, Christopher; Anderson, G Harvey

2014-12-01

Whether pulse components can be used as value-added ingredients in foods formulated for blood glucose (BG) and food intake (FI) control requires investigation. The objective of this study was to examine of the effects of pea components on FI at an ad libitum meal, as well as appetite and BG responses before and after the meal. In a repeated-measures crossover trial, men (n = 15) randomly consumed (i) pea hull fibre (7 g), (ii) pea protein (10 g), (iii) pea protein (10 g) plus hull fibre (7 g), (iv) yellow peas (406 g), and (v) control. Pea hull fibre and protein were served with tomato sauce and noodles, while yellow peas were served with tomato sauce. Control was noodles and tomato sauce. FI was measured at a pizza meal (135 min). Appetite and BG were measured pre-pizza (0-135 min) and post-pizza (155-215 min). Protein plus fibre and yellow peas led to lower pre-pizza BG area under the curve compared with fibre and control. At 30 min, BG was lower after protein plus fibre and yellow peas compared with fibre and control, whereas at 45 and 75 min, protein plus fibre and yellow peas led to lower BG compared with fibre (p < 0.05). Following the pizza meal (155 min), yellow peas led to lower BG compared with fibre (p < 0.05). No differences were observed in FI or appetite. This trial supports the use of pea components as value-added ingredients in foods designed to improve glycemic control.

Molecular Mechanisms of Root Gravitropism.

PubMed

Su, Shih-Heng; Gibbs, Nicole M; Jancewicz, Amy L; Masson, Patrick H

2017-09-11

Plant shoots typically grow against the gravity vector to access light, whereas roots grow downward into the soil to take up water and nutrients. These gravitropic responses can be altered by developmental and environmental cues. In this review, we discuss the molecular mechanisms that govern the gravitropism of angiosperm roots, where a physical separation between sites for gravity sensing and curvature response has facilitated discovery. Gravity sensing takes place in the columella cells of the root cap, where sedimentation of starch-filled plastids (amyloplasts) triggers a pathway that results in a relocalization to the lower side of the cell of PIN proteins, which facilitate efflux of the plant hormone auxin efflux. Consequently, auxin accumulates in the lower half of the root, triggering bending of the root tip at the elongation zone. We review our understanding of the molecular mechanisms that control this process in primary roots, and discuss recent insights into the regulation of oblique growth in lateral roots and its impact on root-system architecture and soil exploration. Copyright © 2017 Elsevier Ltd. All rights reserved.

Polyamines Interact with Hydroxyl Radicals in Activating Ca2+ and K+ Transport across the Root Epidermal Plasma Membranes1[W

PubMed Central

Zepeda-Jazo, Isaac; Velarde-Buendía, Ana María; Enríquez-Figueroa, René; Bose, Jayakumar; Shabala, Sergey; Muñiz-Murguía, Jesús; Pottosin, Igor I.

2011-01-01

Reactive oxygen species (ROS) are integral components of the plant adaptive responses to environment. Importantly, ROS affect the intracellular Ca2+ dynamics by activating a range of nonselective Ca2+-permeable channels in plasma membrane (PM). Using patch-clamp and noninvasive microelectrode ion flux measuring techniques, we have characterized ionic currents and net K+ and Ca2+ fluxes induced by hydroxyl radicals (OH•) in pea (Pisum sativum) roots. OH•, but not hydrogen peroxide, activated a rapid Ca2+ efflux and a more slowly developing net Ca2+ influx concurrent with a net K+ efflux. In isolated protoplasts, OH• evoked a nonselective current, with a time course and a steady-state magnitude similar to those for a K+ efflux in intact roots. This current displayed a low ionic selectivity and was permeable to Ca2+. Active OH•-induced Ca2+ efflux in roots was suppressed by the PM Ca2+ pump inhibitors eosine yellow and erythrosine B. The cation channel blockers gadolinium, nifedipine, and verapamil and the anionic channel blockers 5-nitro-2(3-phenylpropylamino)-benzoate and niflumate inhibited OH•-induced ionic currents in root protoplasts and K+ efflux and Ca2+ influx in roots. Contrary to expectations, polyamines (PAs) did not inhibit the OH•-induced cation fluxes. The net OH•-induced Ca2+ efflux was largely prolonged in the presence of spermine, and all PAs tested (spermine, spermidine, and putrescine) accelerated and augmented the OH•-induced net K+ efflux from roots. The latter effect was also observed in patch-clamp experiments on root protoplasts. We conclude that PAs interact with ROS to alter intracellular Ca2+ homeostasis by modulating both Ca2+ influx and efflux transport systems at the root cell PM. PMID:21980172

Physicochemical properties and in vitro digestibility of flour and starch from pea (Pisum sativum L.) cultivars.

PubMed

Chung, Hyun-Jung; Liu, Qiang

2012-01-01

Flours and isolated starches from three different cultivars (1544-8, 1658-11 and 1760-8) of pea grown under identical environmental conditions were evaluated for their physicochemical properties and in vitro digestibility. The protein content, total starch content and apparent amylose content of pea flour ranged from 24.4 to 26.3%, 48.8 to 50.2%, and 13.9 to 16.7%, respectively. In pea starches, the 1760-8 showed higher apparent amylose content and total starch content than the other cultivars. Pea starch granules were irregularly shaped, ranging from oval to round with a smooth surface. All pea starches showed C-type X-ray diffraction pattern with relative crystallinity ranging between 23.7 and 24.7%. Pea starch had only a single endothermic transition (12.1-14.2 J/g) in the DSC thermogram, whereas pea flour showed two separate endothermic transitions corresponding to starch gelatinization (4.54-4.71 J/g) and disruption of the amylose-lipid complex (0.36-0.78 J/g). In pea cultivars, the 1760-8 had significantly higher setback and final viscosity than the other cultivars in both pea flour (672 and 1170cP, respectively) and isolated starch (2901 and 4811cP). The average branch chain length of pea starches ranged from 20.1 to 20.3. The 1760-8 displayed a larger proportion of short branch chains, DP (degree of polymerization) 6-12 (21.1%), and a smaller proportion of long branch chains, DP≥37 (8.4%). The RDS, SDS and RS contents of pea flour ranged from 23.7 to 24.1%, 11.3 to 12.8%, and 13.2 to 14.8%, respectively. In pea starches, the 1760-8 showed a lower RDS content but higher SDS and RS contents. The expected glycemic index (eGI), based on the hydrolysis index, ranged from 36.9 to 37.7 and 69.8 to 70.7 for pea flour and isolated pea starch, respectively. Copyright © 2011 Elsevier B.V. All rights reserved.

In vitro digestibility, protein composition and techno-functional properties of Saskatchewan grown yellow field peas (Pisum sativum L.) as affected by processing.

PubMed

Ma, Zhen; Boye, Joyce I; Hu, Xinzhong

2017-02-01

Saskatchewan grown yellow field pea was subjected to different processing conditions including dehulling, micronization, roasting, conventional/microwave cooking, germination, and combined germination and conventional cooking/roasting. Their nutritional and antinutritional compositions, functional properties, microstructure, thermal properties, in vitro protein and starch digestibility, and protein composition were studied. Processed field peas including conventional cooked yellow peas (CCYP), microwave cooked yellow peas (MCYP), germinated-conventional cooked yellow peas (GCCYP), and germinated-roasted yellow peas (GRYP) exhibited the significantly higher in vitro protein digestibility (IVPD), which was in accordance with their significantly lower trypsin inhibitor activity and tannin content. The SDS-PAGE and size exclusion HPLC profiles of untreated pea proteins and their hydrolysates also confirmed the IVPD result that these four treatments facilitated the hydrolysis of pea proteins to a greater extent. The CCYP, MCYP, GCCYP, and GRYP also exhibited significantly higher starch digestibility which was supported by their lower onset (T o ), peak (T p ), and conclusion (T c ) temperatures obtained from DSC thermogram, their lower pasting properties and starch damage results, as well as their distinguished amorphous flakes' configuration observed on the scanning electron microscopic image. LC/ESI-MS/MS analysis following in-gel digests of SDS-PAGE separated proteins allowed detailed compositional characterization of pea proteins. The present study would provide fundamental information to help to better understand the functionality of field peas as ingredients, and particularly in regards to agri-food industry to improve the process efficiency of field peas with enhanced nutritional and techno-functional qualities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Multiple piece turbine rotor blade

DOEpatents

Kimmel, Keith D.; Plank, William L.

2016-07-19

A spar and shell turbine rotor blade with a spar and a tip cap formed as a single piece, the spar includes a bottom end with dovetail or fir tree slots that engage with slots on a top end of a root section, and a platform includes an opening on a top surface for insertion of the spar in which a shell made from an exotic high temperature resistant material is secured between the tip cap and the platform. The spar is tapered to form thinner walls at the tip end to further reduce the weight and therefore a pulling force due to blade rotation. The spar and tip cap piece is made from a NiAL material to further reduce the weight and the pulling force.

Phytotoxicity of veterinary antibiotics to seed germination and root elongation of crops.

PubMed

Pan, Min; Chu, L M

2016-04-01

Large quantities of veterinary antibiotics (VAs) are being used worldwide in agricultural fields through wastewater irrigation and manure application. They cause damages to the ecosystem when discharged into the environment, but there is a lack of information on their toxicity to plants and animals. This study evaluated the phytotoxic effects of five major VAs, namely tetracycline (TC), sulfamethazine (SMZ), norfloxacin (NOR), erythromycin (ERY) and chloramphenicol (CAP), on seed germination and root elongation in lettuce, tomato, carrot and cucumber, and investigated the relationship between their physicochemical properties and phytotoxicities. Results show that these compounds significantly inhibited root elongation (p<0.05), the most sensitive endpoint for the phytotoxicity test. TC was associated with the highest level of toxicity, followed by NOR, ERY, SMZ and CAP. Regarding crop species, lettuce was found to be sensitive to most of the VAs. The median effect concentration (EC50) of TC, SMZ, NOR, ERY and CAP to lettuce was 14.4, 157, 49.4, 68.8 and 204 mg/L, respectively. A quantitative structure-activity relationship (QSAR) model has been established based on the measured data. It is evident that hydrophobicity was the most important factor governing the phytotoxicity of these compounds to seeds, which could be explained by the polar narcosis mechanism. Lettuce is considered a good biomarker for VAs in the environment. According to the derived equation, phytotoxicities of selected VA compounds on different crops can be calculated, which could be applicable to other VAs. Environmental risks of VAs were summarized based on the phytotoxicity results and other persistent factors. Copyright © 2015 Elsevier Inc. All rights reserved.

Estimating demand for perennial pigeon pea in Malawi using choice experiments.

PubMed

Waldman, Kurt B; Ortega, David L; Richardson, Robert B; Snapp, Sieglinde S

2017-01-01

Perennial crops have numerous ecological and agronomic advantages over their annual counterparts. We estimate discrete choice models to evaluate farmers' preferences for perennial attributes of pigeon pea intercropped with maize in central and southern Malawi. Pigeon pea is a nitrogen-fixing leguminous crop, which has the potential to ameliorate soil fertility problems related to continuous maize cultivation, which are common in Southern Africa. Adoption of annual pigeon pea is relatively low but perennial production of pigeon pea may be more appealing to farmers due to some of the ancillary benefits associated with perenniality. We model perennial production of pigeon pea as a function of the attributes that differ between annual and perennial production: lower labor and seed requirements resulting from a single planting with multiple harvests, enhanced soil fertility and higher levels of biomass production. The primary tradeoff associated with perennial pigeon pea intercropped with maize is competition with maize in subsequent years of production. While maize yield is approximately twice as valuable to farmers as pigeon pea yield, we find positive yet heterogeneous demand for perenniality driven by soil fertility improvements and pigeon pea grain yield.

Phenylethylamine induces an increase in cytosolic Ca2+ in yeast.

PubMed

Pinontoan, Reinhard; Krystofova, Svetlana; Kawano, Tomonori; Mori, Izumi C; Tsuji, Frederick I; Iida, Hidetoshi; Muto, Shoshi

2002-05-01

Beta-phenylethylamine (PEA) induced an increase in cytosolic free calcium ion concentration ([Ca2+]c) in Saccharomyces cerevisiae cells monitored with transgenic aequorin, a Ca2+-dependent photoprotein. The PEA-induced [Ca2+]c increase was dependent on the concentrations of PEA applied, and the Ca2+ mostly originated from an extracellular source. Preceding the Ca2+ influx, H2O2 was generated in the cells by the addition of PEA. Externally added H2O2 also induced a [Ca2+]c increase. These results suggest that PEA induces the [Ca2+]c increase via H2O2 generation. The PEA-induced [Ca2+]c increase occurred in the mid1 mutant with a slightly smaller peak than in the wild-type strain, indicating that Mid1, a stretch-activated nonselective cation channel, may not be mainly involved in the PEA-induced Ca2+ influx. When PEA was applied, the MATa mid1 mutant was rescued from alpha-factor-induced death in a Ca2+-limited medium, suggesting that the PEA-induced [Ca2+]c increase can reinforce calcium signaling in the mating pheromone response pathway.

Assimilation and conversion of 3,4-benzpyrene by plants under sterile conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Durmishidze, S.V.; Devdariani, T.V.; Kavtaradze, L.K.

1974-01-01

In this article the authors discuss the results of the oxidative conversion of BP to various individual compounds in plant roots and leaves. The experiments were conducted on 14-day alfalfa plants (Medicago sativa), ryegrass (Lolium multiflorum), chick-pea (Cicer arientinum), cucumbers (Cucumis sativus), pumpkin (Cucurbita), orchard grass (Dactylis glomerata), and vetch (Vicia faba), grown under sterile conditions on Knop's nutrient medium. Labeled 1,2-/sup 14/C-BP was synthesized in several steps using phthalic and 1,2-/sup 14/C-acetic anhydrides as the starting materials. The results of the experiments showed that the roots and leaves of various plants assimilate BP and subject it to profound chemicalmore » transformations. The conversion products are transported from the roots to the leaves and from the leaves to the roots. Low-molecular weight compounds, in particular, organic acids, provided most radioactive. The distribution of the radioactivity of the low-molecular weight substances among the plant organs depends on the site of the primary assimilation of 1,2-/sup 14/C-BP. In the case of assimilation of BP by the roots, the most radioactive are the low-molecular weight compounds of the root themselves, while in the case of assimilation of BP by the leaves, the most radioactive are the low-molecular weight compounds of the leaves. The same pattern is observed in the distribution of radioactivity among the organs of plants in the case of organic acids.« less

40 CFR 180.574 - Fluazinam; tolerances for residues.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Onion, bulb, subgroup 3-07A 0.20 Pea and bean, dried shelled, except soybean, subgroup 6C, except pea 0.02 Pea and bean, succulent shelled, subgroup 6B, except pea 0.04 Peanut 0.02 Potato 0.02 Turnip...

Hypolipidemic effect of dietary pea proteins: Impact on genes regulating hepatic lipid metabolism.

PubMed

Rigamonti, Elena; Parolini, Cinzia; Marchesi, Marta; Diani, Erika; Brambilla, Stefano; Sirtori, Cesare R; Chiesa, Giulia

2010-05-01

Controversial data on the lipid-lowering effect of dietary pea proteins have been provided and the mechanisms behind this effect are not completely understood. The aim of the study was to evaluate a possible hypolipidemic activity of a pea protein isolate and to determine whether pea proteins could affect the hepatic lipid metabolism through regulation of genes involved in cholesterol and fatty acid homeostasis. Rats were fed Nath's hypercholesterolemic diets for 28 days, the protein sources being casein or a pea protein isolate from Pisum sativum. After 14 and 28 days of dietary treatment, rats fed pea proteins had markedly lower plasma cholesterol and triglyceride levels than rats fed casein (p<0.05). Pea protein-fed rats displayed higher hepatic mRNA levels of LDL receptor versus those fed casein (p<0.05). Hepatic mRNA concentration of genes involved in fatty acids synthesis, such as fatty acid synthase and stearoyl-CoA desaturase, was lower in pea protein-fed rats than in rats fed casein (p<0.05). In conclusion, the present study demonstrates a marked cholesterol and triglyceride-lowering activity of pea proteins in rats. Moreover, pea proteins appear to affect cellular lipid homeostasis by upregulating genes involved in hepatic cholesterol uptake and by downregulating fatty acid synthesis genes.

Pre-fractionation strategies to resolve pea (Pisum sativum) sub-proteomes

PubMed Central

Meisrimler, Claudia-Nicole; Menckhoff, Ljiljana; Kukavica, Biljana M.; Lüthje, Sabine

2015-01-01

Legumes are important crop plants and pea (Pisum sativum L.) has been investigated as a model with respect to several physiological aspects. The sequencing of the pea genome has not been completed. Therefore, proteomic approaches are currently limited. Nevertheless, the increasing numbers of available EST-databases as well as the high homology of the pea and medicago genome (Medicago truncatula Gaertner) allow the successful identification of proteins. Due to the un-sequenced pea genome, pre-fractionation approaches have been used in pea proteomic surveys in the past. Aside from a number of selective proteome studies on crude extracts and the chloroplast, few studies have targeted other components such as the pea secretome, an important sub-proteome of interest due to its role in abiotic and biotic stress processes. The secretome itself can be further divided into different sub-proteomes (plasma membrane, apoplast, cell wall proteins). Cell fractionation in combination with different gel-electrophoresis, chromatography methods and protein identification by mass spectrometry are important partners to gain insight into pea sub-proteomes, post-translational modifications and protein functions. Overall, pea proteomics needs to link numerous existing physiological and biochemical data to gain further insight into adaptation processes, which play important roles in field applications. Future developments and directions in pea proteomics are discussed. PMID:26539198

Relating physico-chemical properties of frozen green peas (Pisum sativum L.) to sensory quality.

PubMed

Nleya, Kathleen M; Minnaar, Amanda; de Kock, Henriëtte L

2014-03-30

The acceptability of frozen green peas depends on their sensory quality. There is a need to relate physico-chemical parameters to sensory quality. In this research, six brands of frozen green peas representing product sold for retail and caterer's markets were purchased and subjected to descriptive sensory evaluation and physico-chemical analyses (including dry matter content, alcohol insoluble solids content, starch content, °Brix, residual peroxidase activity, size sorting, hardness using texture analysis and colour measurements) to assess and explain product quality. The sensory quality of frozen green peas, particularly texture properties, were well explained using physico-chemical methods of analysis notably alcohol insoluble solids, starch content, hardness and °Brix. Generally, retail class peas were of superior sensory quality to caterer's class peas although one caterer's brand was comparable to the retail brands. Retail class peas were sweeter, smaller, greener, more moist and more tender than the caterer's peas. Retail class peas also had higher °Brix, a(*) , hue and chroma values; lower starch, alcohol insoluble solids, dry matter content and hardness measured. The sensory quality of frozen green peas can be partially predicted by measuring physico-chemical parameters particularly °Brix and to a lesser extent hardness by texture analyser, alcohol insoluble solids, dry matter and starch content. © 2013 Society of Chemical Industry.

Products of dark CO sub 2 fixation in pea root nodules support bacteroid metabolism. [Pisum sativum L

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rosendahl, L.; Pedersen, W.B.; Vance, C.P.

1990-05-01

Products of the nodule cytosol in vivo dark ({sup 14}C)CO{sub 2} fixation were detected in the plant cytosol as well as in the bacteroids of pea (Pisum sativum L. cv Bodil) nodules. The distribution of the metabolites of the dark CO{sub 2} fixation products was compared in effective (fix{sup +}) nodules infected by a wild-type Rhizobium leguminosarum (MNF 300), and ineffective (fix{sup {minus}}) nodules of the R. leguminosarum mutant MNF 3080. The latter has a defect in the dicarboxylic acid transport system of the bacterial membrane. The {sup 14}C incorporation from ({sup 14}C)CO{sub 2} was about threefold greater in themore » wild-type nodules than in the mutant nodules. Similarly, in wild-type nodules the in vitro phosphoenolpyruvate carboxylase activity was substantially greater than that of the mutant. Almost 90% of the {sup 14}C label in the cytosol was found in organic acids in both symbioses. The results indicate a central role for nodule cytosol dark CO{sub 2} fixation in the supply of the bacteroids with dicarboxylic acids.« less

Isolation and characterization of novel plant growth promoting Micrococcus sp NII-0909 and its interaction with cowpea.

PubMed

Dastager, Syed G; Deepa, C K; Pandey, Ashok

2010-12-01

A phosphate-solubilizing bacterial strain NII-0909 isolated from the Western ghat forest soil in India was identified as Micrococcus sp on the basis of phenotypic characteristics, carbon source utilization pattern, fatty acid methyl esters analysis, and 16S rRNA gene sequence. The strain exhibited the plant growth-promoting attributes of phosphate solubilization, auxin production, 1-aminocyclopropane-1-carboxylate deaminase activity, and siderophore production. It was able to solubilize (122.4μg of Ca(3)PO(4) ml(-1)), and produce IAA (109μgml(-1)) at 30°C. P-solubilizing activity of the strain NII-0909 was associated with the release of organic acids and a drop in the pH of the NBRIP medium. HPLC analysis detected two organic acids in the course of P-solubilization. A significant increase in the growth of cow pea was recorded for inoculations under controlled conditions. Scanning electron microscopic study revealed the root colonization of strain on cow pea seedlings. These results demonstrate that isolates NII-0909 has the promising PGPR attributes to be develop as a biofertilizer to enhance soil fertility and promote the plant growth. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

Geoperception in primary and lateral roots of Phaseolus vulgaris (Fabaceae). III. A model to explain the differential georesponsiveness of primary and lateral roots

NASA Technical Reports Server (NTRS)

Ransom, J. S.; Moore, R.

1985-01-01

Half-tipped primary and lateral roots of Phaseolus vulgaris bend toward the side of the root on which the intact half tip remains. Therefore, tips of lateral and primary roots produce growth effectors capable of inducing gravicurvature. The asymmetrical placement of a tip of a lateral root onto a detipped primary root results in the root bending toward the side of the root onto which the tip was placed. That is, the lesser graviresponsiveness of lateral roots as compared with primary roots is not due to the inability of their caps to produce growth inhibitors. The more pronounced graviresponsiveness of primary roots is positively correlated with the presence of columella tissues that are 3.8 times longer, 1.7 times wider, and 10.5 times more voluminous than the columellas of lateral roots. We propose that the lack of graviresponsiveness exhibited by lateral roots is due to the fact that they (i) produce smaller amounts of the inhibitor than primary (i.e., strongly graviresponsive) roots and (ii) are unable to redistribute the inhibitor so as to be able to create a concentration gradient sufficient to induce a pronounced gravitropic response.

Fatty Acid Synthesis in Pea Root Plastids Is Inhibited by the Action of Long-Chain Acyl- Coenzyme As on Metabolite Transporters1

PubMed Central

Fox, Simon R.; Rawsthorne, Stephen; Hills, Matthew J.

2001-01-01

The uptake in vitro of glucose (Glc)-6-phosphate (Glc-6-P) into plastids from the roots of 10- to 14-d-old pea (Pisum sativum L. cv Puget) plants was inhibited by oleoyl-coenzyme A (CoA) concentrations in the low micromolar range (1–2 μm). The IC50 (the concentration of inhibitor that reduces enzyme activity by 50%) for the inhibition of Glc-6-P uptake was approximately 750 nm; inhibition was reversed by recombinant rapeseed (Brassica napus) acyl-CoA binding protein. In the presence of ATP (3 mm) and CoASH (coenzyme A; 0.3 mm), Glc-6-P uptake was inhibited by 60%, due to long-chain acyl-CoA synthesis, presumably from endogenous sources of fatty acids present in the preparations. Addition of oleoyl-CoA (1 μm) decreased carbon flux from Glc-6-P into the synthesis of starch and through the oxidative pentose phosphate (OPP) pathway by up to 73% and 40%, respectively. The incorporation of carbon from Glc-6-P into fatty acids was not detected under any conditions. Oleoyl-CoA inhibited the incorporation of acetate into fatty acids by 67%, a decrease similar to that when ATP was excluded from incubations. The oleoyl-CoA-dependent inhibition of fatty acid synthesis was attributable to a direct inhibition of the adenine nucleotide translocator by oleoyl-CoA, which indirectly reduced fatty acid synthesis by ATP deprivation. The Glc-6-P-dependent stimulation of acetate incorporation into fatty acids was reversed by the addition of oleoyl-CoA. PMID:11457976

The pattern of shikimate pathway and phenylpropanoids after inhibition by glyphosate or quinate feeding in pea roots.

PubMed

Zabalza, Ana; Orcaray, Luis; Fernández-Escalada, Manuel; Zulet-González, Ainhoa; Royuela, Mercedes

2017-09-01

The shikimate pathway is a metabolic route for the biosynthesis of aromatic amino acids (AAAs) (i.e. phenylalanine, tyrosine, and tryptophan). A key enzyme of shikimate pathway (5-enolpyruvylshikimate-3-phosphate synthase, EPSPS) is the target of the widely used herbicide glyphosate. Quinate is a compound synthesized in plants through a side branch of the shikimate pathway. Glyphosate provokes quinate accumulation and exogenous quinate application to plants shows a potential role of quinate in the toxicity of the herbicide glyphosate. Based on this, we hypothesized that the role of quinate accumulation in the toxicity of the glyphosate would be mediated by a deregulation of the shikimate pathway. In this study the effect of the glyphosate and of the exogenous quinate was evaluated in roots of pea plants by analyzing the time course of a full metabolic map of several metabolites of shikimate and phenylpropanoid pathways. Glyphosate application induced an increase of the 3-deoxy-D-arabino-heptulosonate-7-phosphate synthase (DAHPS, first enzyme of the shikimate pathway) protein and accumulation of metabolites upstream of the enzyme EPSPS. No common effects on the metabolites and regulation of shikimate pathway were detected between quinate and glyphosate treatments, supporting that the importance of quinate in the mode of action of glyphosate is not mediated by a common alteration of the regulation of the shikimate pathway. Contrary to glyphosate, the exogenous quinate supplied was probably incorporated into the main trunk from the branch pathway and accumulated in the final products, such as lignin, concomitant with a decrease in the amount of DAHPS protein. Copyright © 2016 Elsevier B.V. All rights reserved.

Metabolism of inositol(1,4,5)trisphosphate by a soluble enzyme fraction from pea (Pisum sativum) roots

DOE Office of Scientific and Technical Information (OSTI.GOV)

Drobak, B.K.; Watkins, P.A.C.; Roberts, K.

1991-02-01

Metabolism of the putative messenger molecule D-myo-inositol(1,4,5)trisphosphate (Ins(1,4,5)P{sub 3}) in plant cells has been studied using a soluble fraction from pea (pisum sativum) roots as enzyme source and (5-{sup 32}P)Ins(1,4,5)P{sub 3} and (2-{sup 3}H)Ins(1,4,5)P{sub 3} as tracers. Ins(1,4,5)P{sub 3} was rapidly converted into both lower and higher inositol phosphates. The major dephosphorylation product was inositol (4,5) bisphosphate (Ins(4,5)P{sub 2}) whereas inositol(1,4)bisphosphate (Ins(1,4)P{sub 2}) was only present in very small quantities throughout a 15 minute incubation period. In addition to these compounds, small amounts of nine other metabolites were produced including inositol and inositol(1,4,5,X)P{sub 4}. Dephosphorylation of Ins(1,4,5)P{sub 3} to Ins(4,5)P{submore » 2} was dependent on Ins(1,4,5)P{sub 3} concentration and was partially inhibited by the phosphohydrolase inhibitors 2,3-diphosphoglycerate, glucose 6-phosphate, and p-nitrophenylphosphate. Conversion of Ins(1,4,5)P{sub 3} to Ins(4,5)P{sub 2} and Ins(1,4,5,X)P{sub 4} was inhibited by 55 micromolar Ca{sup 2+}. This study demonstrates that enzymes are present in plant tissues which are capable of rapidly converting Ins(1,4,5)P{sub 3} and that pathways of inositol phosphate metabolism exist which may prove to be unique to the plant kingdom.« less

Origin of the Words Denoting Some of the Most Ancient Old World Pulse Crops and Their Diversity in Modern European Languages

PubMed Central

Mikić, Aleksandar

2012-01-01

This preliminary research was aimed at finding the roots in various Eurasian proto-languages directly related to pulses and giving the words denoting the same in modern European languages. Six Proto-Indo-European roots were indentified, namely arnk(')- (‘a leguminous plant’), *bhabh- (‘field bean’), * (‘a kernel of leguminous plant’, ‘pea’), ghArs- (‘a leguminous plant’), *kek- (‘pea’) and *lent- (‘lentil’). No Proto-Uralic root was attested save hypothetically *kača (‘pea’), while there were two Proto-Altaic roots, *bŭkrV (‘pea’) and * (‘lentil’). The Proto-Caucasianx root * denoted pea, while another one, *hōwł(ā) (‘bean’, ‘lentil’) and the Proto-Basque root *iłha-r (‘pea’, ‘bean’, ‘vetch’) could have a common Proto-Sino-Caucasian ancestor, *hVwłV (‘bean’) within the hypothetic Dené-Caucasian language superfamily. The Modern Maltese preserved the memory of two Proto-Semitic roots, *'adaš- (‘lentil’) and *pūl- (‘field bean’). The presented results prove that the most ancient Eurasian pulse crops were well-known and extensively cultivated by the ancestors of all modern European nations. The attested lexicological continuum witnesses the existence of a millennia-long links between the peoples of Eurasia to their mutual benefit. This research is meant to encourage interdisciplinary concerted actions between plant scientists dealing with crop evolution and biodiversity, archaeobotanists and language historians. PMID:22973458

Peas in a Pod: Environment and Ionization in Green Pea Galaxies

NASA Astrophysics Data System (ADS)

Kurtz, Heather; Jaskot, Anne; Drew, Patrick; Pare, Dylan; Griffin, Jon; Petersen, Michael

2016-01-01

The Green Peas are extreme, highly ionized, starburst galaxies with strong [OIII] 5007 emission. Using the Sloan Digital Sky Survey, we present statistics on the environment of Green Peas and investigate its effects on their ionized gas properties. Although most dwarf starburst galaxies are in low-density environments, we identify a sample of Green Peas in dense environments. Emission line observations with the WIYN 0.9-meter telescope at Kitt Peak reveal that one cluster Green Pea is more highly ionized in the direction of the cluster center. Ram pressure stripping likely generates this ionization gradient. We explore the role of the environment in enhancing star formation rates and ionization, and we compare the nebular properties of Green Peas in high-density environments to those in low-density environments.

Molecular and morphological surface analysis: effect of filling pastes and cleaning agents on root dentin

PubMed Central

DAINEZI, Vanessa Benetello; IWAMOTO, Alexsandra Shizue; MARTIN, Airton Abrahão; SOARES, Luís Eduardo Silva; HOSOYA, Yumiko; PASCON, Fernanda Miori; PUPPIN-RONTANI, Regina Maria

2017-01-01

Abstract The quality of the dentin root is the most important factor for restoration resin sealing and drives the outcome of endodontic treatment. Objective This study evaluated the effect of different filling pastes and cleaning agents on the root dentin of primary teeth using Fourier-transformed Raman spectroscopy (FT-Raman), micro energy-dispersive X-ray fluorescence (µ-EDXRF) and scanning electron microscopic (SEM) analysis. Material and Methods Eighty roots of primary teeth were endodontically prepared and distributed into 4 groups and filled according to the following filling pastes: Control-no filling (CP), Calen®+zinc oxide (CZ), Calcipex II® (CII), Vitapex® (V). After seven days, filling paste groups were distributed to 4 subgroups according to cleaning agents (n=5): Control-no cleaning (C), Ethanol (E), Tergenform® (T), 35% Phosphoric acid (PA). Then, the roots were sectioned and the dentin root sections were internally evaluated by FT-Raman, µ-EDXRF and SEM. Data was submitted to two-way ANOVA and Tukey tests (α=0.05). Results Regarding filling pastes, there was no significant difference in organic content. CP provided the lowest calcium values and, calcium/phosphoric ratio (Ca/P), and the highest phosphoric values. For cleaning agents there was no difference in organic content when compared to the C; however, T showed significantly higher calcium and Ca/P than PA. All groups showed similar results for phosphorus. The dentin smear layer was present after use of the cleaning agents, except PA. Conclusion The filling pastes changed the inorganic content, however they did not change the organic content. Cleaning agents did not alter the inorganic and organic content. PA cleaned and opened dentin tubules. PMID:28198982

Autogenous teeth used for bone grafting: a comparison with traditional grafting materials.

PubMed

Kim, Young-Kyun; Kim, Su-Gwan; Yun, Pil-Young; Yeo, In-Sung; Jin, Seung-Chan; Oh, Ji-Su; Kim, Heung-Joong; Yu, Sun-Kyoung; Lee, Sook-Young; Kim, Jae-Sung; Um, In-Woong; Jeong, Mi-Ae; Kim, Gyung-Wook

2014-01-01

This study evaluated the surface structures and physicochemical characteristics of a novel autogenous tooth bone graft material currently in clinical use. The material's surface structure was compared with a variety of other bone graft materials via scanning electron microscope (SEM). The crystalline structure of the autogenous tooth bone graft material from the crown (AutoBT crown) and root (AutoBT root), xenograft (BioOss), alloplastic material (MBCP), allograft (ICB), and autogenous mandibular cortical bone were compared using x-ray diffraction (XRD) analysis. The solubility of each material was measured with the Ca/P dissolution test. The results of the SEM analysis showed that the pattern associated with AutoBT was similar to that from autogenous cortical bones. In the XRD analysis, AutoBT root and allograft showed a low crystalline structure similar to that of autogenous cortical bones. In the CaP dissolution test, the amount of calcium and phosphorus dissolution in AutoBT was significant from the beginning, while displaying a pattern similar to that of autogenous cortical bones. In conclusion, autogenous tooth bone graft materials can be considered to have physicochemical characteristics similar to those of autogenous bones. Copyright © 2014 Elsevier Inc. All rights reserved.

β-Phenylethylamine requires the dopamine transporter to increase extracellular dopamine in Caenorhabditis elegans dopaminergic neurons.

PubMed

Hossain, Murad; Wickramasekara, Rochelle N; Carvelli, Lucia

2014-07-01

β-Phenylethylamine (βPEA) is an endogenous amine that has been shown to increase the synaptic levels of dopamine (DA). A number of in vitro and behavioral studies suggest the dopamine transporter (DAT) plays a role in the effects generated by βPEA, however the mechanism through which βPEA affects DAT has not yet been elucidated. Here, we used Caenorhabditis (C.) elegans DAT (DAT-1) expressing LLC-pk1 cells and neuronal cultures to investigate whether the βPEA-induced increase of extracellular DA required DAT-1. Our data show that βPEA increases extracellular dopamine both in DAT-1 transfected cells and cultures of differentiated neurons. RTI-55, a cocaine homologue and DAT inhibitor, completely blocked the βPEA-induced effect in transfected cells. However in neuronal cultures, RTI-55 only partly inhibited the increase of extracellular DA generated by βPEA. These results suggest that βPEA requires DAT-1 and other, not yet identified proteins, to increase extracellular DA when tested in a native system. Furthermore, our results suggest that βPEA-induced increase of extracellular DA does not require functional monoamine vesicles as genetic ablation of the C. elegans homologue vesicular monoamine transporter, cat-1, did not compromise the ability of βPEA to increase extracellular DA. Finally, our electrophysiology data show that βPEA caused fast-rising and self-inactivating amperometric currents in a subset of wild-type DA neurons but not in neurons isolated from dat-1 knockout animals. Taken together, these data demonstrate that in both DA neurons and heterogeneous cultures of differentiated C. elegans neurons, βPEA releases cytoplasmic DA through DAT-1 to ultimately increase the extracellular concentration of DA. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of beta-phenylethylamine on extracellular concentrations of dopamine in the nucleus accumbens and prefrontal cortex.

PubMed

Murata, Mikio; Katagiri, Nobuyuki; Ishida, Kota; Abe, Kenji; Ishikawa, Masago; Utsunomiya, Iku; Hoshi, Keiko; Miyamoto, Ken-ichi; Taguchi, Kyoji

2009-05-07

It is known that psychostimulants stimulate dopamine transmission in the nucleus accumbens. In the present study, we examined the effects of systemically administered beta-phenylethylamine (beta-PEA), a psychomotor-stimulating trace amine, on dopamine concentrations in the nucleus accumbens and prefrontal cortex in freely moving rats, using an in vivo microdialysis technique. Intraperitoneal administration of beta-PEA (12.5 and 25 mg/kg) significantly increased extracellular dopamine levels in the nucleus accumbens shell. The observed increase in the dopamine concentration in nucleus accumbens shell dialysate after intraperitoneal administration of 25 mg/kg beta-PEA was inhibited by pre-treatment with a dopamine uptake inhibitor, GBR12909 (10 mg/kg, i.p.). In contrast, beta-PEA (25 mg/kg, i.p.) did not affect dopamine release in the nucleus accumbens core. Although a high dose of beta-PEA (50 mg/kg) significantly increased dopamine levels in the nucleus accumbens core, the dopamine increasing effect of beta-PEA was more potent in the nucleus accumbens shell. Systemic administration of 12.5 and 25 mg/kg beta-PEA also increased extracellular dopamine levels in the prefrontal cortex of rats. However, systemic 25 mg/kg beta-PEA-induced increases in extracellular dopamine levels were not blocked by GBR12909 within the prefrontal cortex. These results suggest that beta-PEA has a greater effect in the shell than in the core and low-dose beta-PEA stimulates dopamine release in the nucleus accumbens shell through uptake by a dopamine transporter. Similarly, beta-PEA increased extracellular dopamine levels in the prefrontal cortex. Thus, beta-PEA may increase extracellular dopamine concentrations in the mesocorticolimbic pathway.

β-phenylethylamine Requires the Dopamine Transporter to Increase Extracellular Dopamine in C. elegans Dopaminergic Neurons

PubMed Central

Hossain, Murad; Wickramasekara, Rochelle N.; Carvelli, Lucia

2013-01-01

β-phenylethylamine (βPEA) is an endogenous amine that has been shown to increase the synaptic levels of dopamine (DA). A number of in vitro and behavioral studies suggest the dopamine transporter (DAT) plays a role in the effects generated by βPEA, however the mechanism through which βPEA affects DAT has not yet been elucidated. Here, we used Caenorhabditis (C.) elegans DAT (DAT-1) expressing LLC-pk1 cells and neuronal cultures to investigate whether the βPEA-induced increase of extracellular DA required DAT-1. Our data show that βPEA increases extracellular dopamine both in DAT-1 transfected cells and cultures of differentiated neurons. RTI-55, a cocaine homologue and DAT inhibitor, completely blocked the βPEA-induced effect in transfected cells. However in neuronal cultures, RTI-55 only partly inhibited the increase of extracellular DA generated by βPEA. These results suggest that βPEA requires DAT-1 and other, not yet identified proteins, to increase extracellular DA when tested in a native system. Furthermore, our results suggest that βPEA-induced increase of extracellular DA does not require functional monoamine vesicles as genetic ablation of the C. elegans homologue vesicular monoamine transporter, cat-1, did not compromise the ability of βPEA to increase extracellular DA. Finally, our electrophysiology data show that βPEA caused fast-rising and self-inactivating amperometric currents in a subset of wild-type DA neurons but not in neurons isolated from dat-1 knockout animals. Taken together, these data demonstrate that in both DA neurons and heterogeneous cultures of differentiated C. elegans neurons, βPEA releases cytoplasmic DA through DAT-1 to ultimately increase the extracellular concentration of DA. PMID:24161617

NUTRALYS® pea protein: characterization of in vitro gastric digestion and in vivo gastrointestinal peptide responses relevant to satiety

PubMed Central

Overduin, Joost; Guérin-Deremaux, Laetitia; Wils, Daniel; Lambers, Tim T.

2015-01-01

Background Pea protein (from Pisum sativum) is under consideration as a sustainable, satiety-inducing food ingredient. Objective In the current study, pea-protein-induced physiological signals relevant to satiety were characterized in vitro via gastric digestion kinetics and in vivo by monitoring post-meal gastrointestinal hormonal responses in rats. Design Under in vitro simulated gastric conditions, the digestion of NUTRALYS® pea protein was compared to that of two dairy proteins, slow-digestible casein and fast-digestible whey. In vivo, blood glucose and gastrointestinal hormonal (insulin, ghrelin, cholecystokinin [CCK], glucagon-like peptide 1 [GLP-1], and peptide YY [PYY]) responses were monitored in nine male Wistar rats following isocaloric (11 kcal) meals containing 35 energy% of either NUTRALYS® pea protein, whey protein, or carbohydrate (non-protein). Results In vitro, pea protein transiently aggregated into particles, whereas casein formed a more enduring protein network and whey protein remained dissolved. Pea-protein particle size ranged from 50 to 500 µm, well below the 2 mm threshold for gastric retention in humans. In vivo, pea-protein and whey-protein meals induced comparable responses for CCK, GLP-1, and PYY, that is, the anorexigenic hormones. Pea protein induced weaker initial, but equal 3-h integrated ghrelin and insulin responses than whey protein, possibly due to the slower gastric breakdown of pea protein observed in vitro. Two hours after meals, CCK levels were more elevated in the case of protein meals compared to that of non-protein meals. Conclusions These results indicate that 1) pea protein transiently aggregates in the stomach and has an intermediately fast intestinal bioavailability in between that of whey and casein; 2) pea-protein- and dairy-protein-containing meals were comparably efficacious in triggering gastrointestinal satiety signals. PMID:25882536

Rhizophores in Rhizophora mangle L: an alternative interpretation of so-called ''aerial roots''.

PubMed

Menezes, Nanuza L de

2006-06-01

Rhizophora mangle L., one of the most common mangrove species, has an aerial structure system that gives it stability in permanently swampy soils. In fact, these structures, known as "aerial roots" or "stilt roots", have proven to be peculiar branches with positive geotropism, which form a large number of roots when in contact with swampy soils. These organs have a sympodial branching system, wide pith, slightly thickened cortex, collateral vascular bundles, polyarch stele and endarch protoxylem, as in the stem, and a periderm produced by a phellogen at the apex similar to a root cap. They also have the same type of trichosclereid that occurs in the stem, with negative geotropism, unlike true Rhizophora roots, which do not form trichosclereids at all. On the other hand, these branches do not form leaves and in this respect they are similar to roots. These peculiar branches are rhizophores or special root-bearing branches, analogous to those found in Lepidodendrales and other Carboniferous tree ferns that grew in swampy soils.

40 CFR 180.314 - Triallate; tolerances for residues.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., tops 0.5 Pea, dry 0.2 Pea, field, hay 1.0 Pea, field, vines 0.5 Pea, succulent 0.2 Wheat, forage 0.5 Wheat, grain 0.05 Wheat, hay 1.0 Wheat, straw 1.0 (d) Indirect or inadvertent residues. [Reserved] [72...

Capsaicin-induced activation of ERK1/2 and its involvement in GAP-43 expression and CGRP depletion in organotypically cultured DRG neurons.

PubMed

Li, Yunfeng; Liu, Guixiang; Li, Hao; Xu, Youzheng; Zhang, Hong; Liu, Zhen

2013-04-01

Low concentrations of capsaicin (CAP) stimulate and high concentrations of CAP can be toxic to the primary sensory neurons of the dorsal root ganglion (DRG). CAP induces the phosphorylation of extracellular signal-regulated protein kinases 1/2 (ERK1/2) in DRG neurons. The effect of the activation of ERK1/2 by different concentrations of CAP on growth-associated protein 43 (GAP-43) expression and calcitonin gene-related peptide (CGRP) depletion in DRG neurons remains unknown. In the present study, organotypic embryonic 15-day-old rat DRG explants were used to determine the effect of different concentrations of CAP on GAP-43 expression and CGRP depletion. The results showed that, compared to unstimulated control cultures, GAP-43 and pERK1/2 protein levels increased at a low concentration (2 μmol/L) of CAP and decreased at a higher concentration (10 μmol/L). The number of CGRP-immunoreactive (IR) migrating neurons also decreased in CAP-treated cultures. The increase in GAP-43 levels and CGRP depletion could be blocked by the administration of ERK1/2 inhibitor PD98059. The results of the present study imply that CAP at different concentrations has different effects on GAP-43 expression and CGRP depletion. These effects were involved in the activation of ERK1/2 in organotypically cultured DRG neurons stimulated with CAP. These data may provide new insights for further development potential therapeutic applications of CAP with moderate dose on neurogenic inflammation.

Root hydrotropism is controlled via a cortex-specific growth mechanism.

PubMed

Dietrich, Daniela; Pang, Lei; Kobayashi, Akie; Fozard, John A; Boudolf, Véronique; Bhosale, Rahul; Antoni, Regina; Nguyen, Tuan; Hiratsuka, Sotaro; Fujii, Nobuharu; Miyazawa, Yutaka; Bae, Tae-Woong; Wells, Darren M; Owen, Markus R; Band, Leah R; Dyson, Rosemary J; Jensen, Oliver E; King, John R; Tracy, Saoirse R; Sturrock, Craig J; Mooney, Sacha J; Roberts, Jeremy A; Bhalerao, Rishikesh P; Dinneny, José R; Rodriguez, Pedro L; Nagatani, Akira; Hosokawa, Yoichiroh; Baskin, Tobias I; Pridmore, Tony P; De Veylder, Lieven; Takahashi, Hideyuki; Bennett, Malcolm J

2017-05-08

Plants can acclimate by using tropisms to link the direction of growth to environmental conditions. Hydrotropism allows roots to forage for water, a process known to depend on abscisic acid (ABA) but whose molecular and cellular basis remains unclear. Here we show that hydrotropism still occurs in roots after laser ablation removed the meristem and root cap. Additionally, targeted expression studies reveal that hydrotropism depends on the ABA signalling kinase SnRK2.2 and the hydrotropism-specific MIZ1, both acting specifically in elongation zone cortical cells. Conversely, hydrotropism, but not gravitropism, is inhibited by preventing differential cell-length increases in the cortex, but not in other cell types. We conclude that root tropic responses to gravity and water are driven by distinct tissue-based mechanisms. In addition, unlike its role in root gravitropism, the elongation zone performs a dual function during a hydrotropic response, both sensing a water potential gradient and subsequently undergoing differential growth.

Physicochemical and sensory characteristics of soy sauce substituted with pigeon pea (Cajanus cajan (Linn.))

NASA Astrophysics Data System (ADS)

Retnaningsih, C.; Sumardi; Meiliana; Surya, A.

2018-01-01

The objective of this study wasto investigate the physicochemical and sensory properties of the soy sauce substituted with pigeon pea. Soybean was substituted by 20%, 50%, 75%, and 100% of pigeon pea. The observation included viscosity, total solids, protein levels, antioxidant activity, and sensory characteristics. The results showed that the more substitution of pigeon pea, the less the protein content of soy sauce and the more the antioxidant activity as well as total solids. The most favored group was 25% pigeon pea substitution. It is suggested that soy sauce could be prepared using 25% to 75% pigeon pea substitution.

β-phenylethylamine, a small molecule with a large impact.

PubMed

Irsfeld, Meredith; Spadafore, Matthew; Prüß, Birgit M

2013-09-30

During a screen of bacterial nutrients as inhibitors of Escherichia coli O157:H7 biofilm, the Prüß research team made an intriguing observation: among 95 carbon and 95 nitrogen sources tested, β-phenylethylamine (PEA) performed best at reducing bacterial cell counts and biofilm amounts, when supplemented to liquid beef broth medium. This review article summarizes what is known about PEA. After some starting information on the chemistry of the molecule, we focus on PEA as a neurotransmitter and then move on to its role in food processing. PEA is a trace amine whose molecular mechanism of action differs from biogenic amines, such as serotonin or dopamine. Especially low or high concentrations of PEA may be associated with specific psychological disorders. For those disorders that are characterized by low PEA levels ( e.g. attention deficit hyperactivity disorder), PEA has been suggested as a 'safe' alternative to drugs, such as amphetamine or methylphenidate, which are accompanied by many undesirable side effects. On the food processing end, PEA can be detected in food either as a result of microbial metabolism or thermal processing. PEA's presence in food can be used as an indicator of bacterial contamination.

β-phenylethylamine, a small molecule with a large impact

PubMed Central

Irsfeld, Meredith; Spadafore, Matthew; Prüß, Birgit M.

2013-01-01

During a screen of bacterial nutrients as inhibitors of Escherichia coli O157:H7 biofilm, the Prüß research team made an intriguing observation: among 95 carbon and 95 nitrogen sources tested, β-phenylethylamine (PEA) performed best at reducing bacterial cell counts and biofilm amounts, when supplemented to liquid beef broth medium. This review article summarizes what is known about PEA. After some starting information on the chemistry of the molecule, we focus on PEA as a neurotransmitter and then move on to its role in food processing. PEA is a trace amine whose molecular mechanism of action differs from biogenic amines, such as serotonin or dopamine. Especially low or high concentrations of PEA may be associated with specific psychological disorders. For those disorders that are characterized by low PEA levels (e.g. attention deficit hyperactivity disorder), PEA has been suggested as a ‘safe’ alternative to drugs, such as amphetamine or methylphenidate, which are accompanied by many undesirable side effects. On the food processing end, PEA can be detected in food either as a result of microbial metabolism or thermal processing. PEA's presence in food can be used as an indicator of bacterial contamination. PMID:24482732

Symbiotic N2 fixation activity in relation to C economy of Pisum sativum L. as a function of plant phenology.

PubMed

Voisin, A S; Salon, C; Jeudy, C; Warembourg, F R

2003-12-01

The relationships between symbiotic nitrogen fixation (SNF) activity and C fluxes were investigated in pea plants (Pisum sativum L. cv. Baccara) using simultaneous 13C and 15N labelling. Analysis of the dynamics of labelled CO2 efflux from the nodulated roots allowed the different components associated with SNF activity to be calculated, together with root and nodule synthetic and maintenance processes. The carbon costs for the synthesis of roots and nodules were similar and decreased with time. Carbon lost by turnover, associated with maintenance processes, decreased with time for nodules while it increased in the roots. Nodule turnover remained higher than root turnover until flowering. The effect of the N source on SNF was investigated using plants supplied with nitrate or plants only fixing N2. SNF per unit nodule biomass (nodule specific activity) was linearly related to the amount of carbon allocated to the nodulated roots regardless of the N source, with regression slopes decreasing across the growth cycle. These regression slopes permitted potential values of SNF specific activity to be defined. SNF activity decreased as the plants aged, presumably because of the combined effects of both increasing C costs of SNF (from 4.0 to 6.7 g C g-1 N) and the limitation of C supply to the nodules. SNF activity competed for C against synthesis and maintenance processes within the nodulated roots. Synthesis was the main limiting factor of SNF, but its importance decreased as the plant aged. At seed-filling, SNF was probably more limited by nodule age than by C supply to the nodulated roots.

78 FR 63160 - United States Standards for Feed Peas, Split Peas, and Lentils

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-23

... DEPARTMENT OF AGRICULTURE Grain Inspection, Packers and Stockyards Administration United States... Administration, USDA ACTION: Notice and request for comments. SUMMARY: The Department of Agriculture's (USDA... Standards for Feed Peas, Split Peas, and Lentils under the Agriculture Marketing Act (AMA) of 1946. To...

Infection by Rhodococcus fascians maintains cotyledons as a sink tissue for the pathogen

PubMed Central

Dhandapani, Pragatheswari; Song, Jiancheng; Novak, Ondrej

2017-01-01

Background and Aims Pisum sativum L. (pea) seed is a source of carbohydrate and protein for the developing plant. By studying pea seeds inoculated by the cytokinin-producing bacterium, Rhodococcus fascians, we sought to determine the impact of both an epiphytic (avirulent) strain and a pathogenic strain on source–sink activity within the cotyledons during and following germination. Methods Bacterial spread was monitored microscopically, and real-time reverse transcription–quantitative PCR was used to determine the expression of cytokinin biosynthesis, degradation and response regulator gene family members, along with expression of family members of SWEET, SUT, CWINV and AAP genes – gene families identified initially in pea by transcriptomic analysis. The endogenous cytokinin content was also determined. Key Results The cotyledons infected by the virulent strain remained intact and turned green, while multiple shoots were formed and root growth was reduced. The epiphytic strain had no such marked impact. Isopentenyl adenine was elevated in the cotyledons infected by the virulent strain. Strong expression of RfIPT, RfLOG and RfCKX was detected in the cotyledons infected by the virulent strain throughout the experiment, with elevated expression also observed for PsSWEET, PsSUT and PsINV gene family members. The epiphytic strain had some impact on the expression of these genes, especially at the later stages of reserve mobilization from the cotyledons. Conclusions The pathogenic strain retained the cotyledons as a sink tissue for the pathogen rather than the cotyledon converting completely to a source tissue for the germinating plant. We suggest that the interaction of cytokinins, CWINVs and SWEETs may lead to the loss of apical dominance and the appearance of multiple shoots. PMID:27864224

The Vigna unguiculata Gene Expression Atlas (VuGEA) from de novo assembly and quantification of RNA-seq data provides insights into seed maturation mechanisms.

PubMed

Yao, Shaolun; Jiang, Chuan; Huang, Ziyue; Torres-Jerez, Ivone; Chang, Junil; Zhang, Heng; Udvardi, Michael; Liu, Renyi; Verdier, Jerome

2016-10-01

Legume research and cultivar development are important for sustainable food production, especially of high-protein seed. Thanks to the development of deep-sequencing technologies, crop species have been taken to the front line, even without completion of their genome sequences. Black-eyed pea (Vigna unguiculata) is a legume species widely grown in semi-arid regions, which has high potential to provide stable seed protein production in a broad range of environments, including drought conditions. The black-eyed pea reference genotype has been used to generate a gene expression atlas of the major plant tissues (i.e. leaf, root, stem, flower, pod and seed), with a developmental time series for pods and seeds. From these various organs, 27 cDNA libraries were generated and sequenced, resulting in more than one billion reads. Following filtering, these reads were de novo assembled into 36 529 transcript sequences that were annotated and quantified across the different tissues. A set of 24 866 unique transcript sequences, called Unigenes, was identified. All the information related to transcript identification, annotation and quantification were stored into a gene expression atlas webserver (http://vugea.noble.org), providing a user-friendly interface and necessary tools to analyse transcript expression in black-eyed pea organs and to compare data with other legume species. Using this gene expression atlas, we inferred details of molecular processes that are active during seed development, and identified key putative regulators of seed maturation. Additionally, we found evidence for conservation of regulatory mechanisms involving miRNA in plant tissues subjected to drought and seeds undergoing desiccation. © 2016 The Authors. The Plant Journal published by Society for Experimental Biology and John Wiley & Sons Ltd.

[Possibility of using flour of pigeon pea in products prepared with rice or wheat flour].

PubMed

Mueses, C; de León, L; Bressani, R

1993-03-01

The present study reports on the development of foods containing processed pigeon pea (Cajanus cajan) flour. The pigeon pea flours described in a previous publication were prepared from dehulled pigeon peas by cooking in autoclave, by extrusion-cooking and by cooking/dehydration by drum-drying. Mixtures of cooked pigeon peas and rice were first evaluated biological through a protein complementation design using NPR. The results of this study showed that the two products had high protein quality and were similar when mixed in ratios of 80:20 to 40:60. For the evaluation of the processed pigeon pea flour, mixtures with rice (80:20) were used. All pigeon pea flours gave similar protein quality values. On the basis of these results three products were developed and tested. One was a gruel ("atole"), a second a fruit-flavored thick drink with and without 15% milk. Cookies were also prepared with a series of blends of pigeon pea flour (extrusion-cooked) and wheat. The gruel and the fruit flavored products had high acceptability based on a sensory evaluation test. Cookies with 100% pigeon pea flour were unacceptable, however, mixtures of 75% wheat flour and 25% pigeon pea flour gave cookies of attractive appearance and good taste. The study showed the possibility of preparing and utilizing tropical grain legume flours for food products of relatively high acceptability and nutritive value.

Addition of sucralose enhances the release of satiety hormones in combination with pea protein.

PubMed

Geraedts, Maartje C P; Troost, Freddy J; Saris, Wim H M

2012-03-01

Exposing the intestine to proteins or tastants, particularly sweet, affects satiety hormone release. There are indications that each sweetener has different effects on this release, and that combining sweeteners with other nutrients might exert synergistic effects on hormone release. STC-1 cells were incubated with acesulfame-K, aspartame, saccharine, sucralose, sucrose, pea, and pea with each sweetener. After a 2-h incubation period, cholecystokinin(CCK) and glucagon-like peptide 1 (GLP-1) concentrations were measured. Using Ussing chamber technology, the mucosal side of human duodenal biopsies was exposed to sucrose, sucralose, pea, and pea with each sweetener. CCK and GLP-1 levels were measured in basolateral secretions. In STC-1 cells, exposure to aspartame, sucralose, sucrose, pea, and pea with sucralose increased CCK levels, whereas GLP-1 levels increased after addition of all test products. Addition of sucrose and sucralose to human duodenal biopsies did not affect CCK and GLP-1 release; addition of pea stimulated CCK and GLP-1 secretion. Combining pea with sucrose and sucralose induced even higher levels of CCK and GLP-1. Synchronous addition of pea and sucralose to enteroendocrine cells induced higher levels of CCK and GLP-1 than addition of each compound alone. This study shows that combinations of dietary compounds synergize to enhance satiety hormone release. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Genomic Tools in Pea Breeding Programs: Status and Perspectives

PubMed Central

Tayeh, Nadim; Aubert, Grégoire; Pilet-Nayel, Marie-Laure; Lejeune-Hénaut, Isabelle; Warkentin, Thomas D.; Burstin, Judith

2015-01-01

Pea (Pisum sativum L.) is an annual cool-season legume and one of the oldest domesticated crops. Dry pea seeds contain 22–25% protein, complex starch and fiber constituents, and a rich array of vitamins, minerals, and phytochemicals which make them a valuable source for human consumption and livestock feed. Dry pea ranks third to common bean and chickpea as the most widely grown pulse in the world with more than 11 million tons produced in 2013. Pea breeding has achieved great success since the time of Mendel's experiments in the mid-1800s. However, several traits still require significant improvement for better yield stability in a larger growing area. Key breeding objectives in pea include improving biotic and abiotic stress resistance and enhancing yield components and seed quality. Taking advantage of the diversity present in the pea genepool, many mapping populations have been constructed in the last decades and efforts have been deployed to identify loci involved in the control of target traits and further introgress them into elite breeding materials. Pea now benefits from next-generation sequencing and high-throughput genotyping technologies that are paving the way for genome-wide association studies and genomic selection approaches. This review covers the significant development and deployment of genomic tools for pea breeding in recent years. Future prospects are discussed especially in light of current progress toward deciphering the pea genome. PMID:26640470

Protein-enriched pea flour extract protects stored milled rice against the rice weevil, Sitophilus oryzae.

PubMed

Pretheep-Kumar, P; Mohan, S; Ramaraju, K

2004-01-01

Studies were conducted to evaluate the effect of a protein-enriched pea (Pisum sativum var. Bonneville) flour extract against the rice weevil, Sitophilus oryzae in its repellency, toxicity, effect on fecundity, stability and sensory properties. Milled rice admixed with pea flour extract at 1% concentration significantly repelled S. oryzae. Mortality of S. oryzae was found to increase and fecundity was markedly suppressed, in rice treated with 1% pea flour extract. The toxicity and reproductive effects of the pea protein-enriched rice were found to be stable for a period of 5 months. The sensory characteristics of stored rice when eaten were not affected by the treatment with pea flour extract. This study indicates that the protein-enriched flour extract obtained from the Bonneville pea may be feasible to protect stored milled rice from insect attack.

Comparative Developmental Anatomy of the Root in Three Species of Cladopus (Podostemaceae)

PubMed Central

KOI, SATOSHI; KATO, MASAHIRO

2003-01-01

Root meristem structure and root branching in three species of Cladopus were investigated from developmental and anatomical perspectives. Cladopus fukiensis has a compressed bell‐shaped meristem at the apex of a compressed subcylindrical root, while C. javanicus and perhaps C. nymanii, with a ribbon‐like root, have a half lozenge‐shaped (⊂ as seen from above) meristem composed of an apical meristem of cubic cells and a marginal meristem of rectangular cells. The dorsiventrality of the meristem results in root dorsiventrality, and a marginal meristem contributes to the broadening of the root. Comparisons of meristem structure and root morphology suggest that the ribbon‐like root of, e.g. C. javanicus, evolved towards the foliose root of Hydrobryum, sister to the genus Cladopus, by loss of an indeterminate apical meristem. The lateral root of C. javanicus initiates within the meristem of a parent root. The dorsal dermal layer and inner cells of the lateral‐root meristem appear endogenously under the dermal layer of the parent root, while the ventral layer is derived exogenously from a ventral dermal layer continuous with the parent‐root meristem. This mosaic pattern of exogenous and endogenous root formation differs from the truly exogenous formation seen in Hydrobryum and Zeylanidium. The dorsiventral mosaic origin of the root meristem may account for root cap asymmetry. PMID:12770848

A Single, Plastic Population of Mycosphaerella pinodes Causes Ascochyta Blight on Winter and Spring Peas (Pisum sativum) in France

PubMed Central

Guibert, Michèle; Leclerc, Aurélie; Andrivon, Didier; Tivoli, Bernard

2012-01-01

Plant diseases are caused by pathogen populations continuously subjected to evolutionary forces (genetic flow, selection, and recombination). Ascochyta blight, caused by Mycosphaerella pinodes, is one of the most damaging necrotrophic pathogens of field peas worldwide. In France, both winter and spring peas are cultivated. Although these crops overlap by about 4 months (March to June), primary Ascochyta blight infections are not synchronous on the two crops. This suggests that the disease could be due to two different M. pinodes populations, specialized on either winter or spring pea. To test this hypothesis, 144 pathogen isolates were collected in the field during the winter and spring growing seasons in Rennes (western France), and all the isolates were genotyped using amplified fragment length polymorphism (AFLP) markers. Furthermore, the pathogenicities of 33 isolates randomly chosen within the collection were tested on four pea genotypes (2 winter and 2 spring types) grown under three climatic regimes, simulating winter, late winter, and spring conditions. M. pinodes isolates from winter and spring peas were genetically polymorphic but not differentiated according to the type of cultivars. Isolates from winter pea were more pathogenic than isolates from spring pea on hosts raised under winter conditions, while isolates from spring pea were more pathogenic than those from winter pea on plants raised under spring conditions. These results show that disease developed on winter and spring peas was initiated by a single population of M. pinodes whose pathogenicity is a plastic trait modulated by the physiological status of the host plant. PMID:23023742

Divergent Pseudomonas exotoxin A sensitivity in normal and transformed liver cells is correlated with low-density lipoprotein receptor-related protein expression.

PubMed

Laithwaite, J E; Benn, S J; Marshall, W S; FitzGerald, D J; LaMarre, J

2001-09-01

Pseudomonas exotoxin A (PEA) is an extracellular virulence factor produced by the opportunistic human pathogen Pseudomonas aerguinosa. PEA intoxification begins when PEA binds to the low-density lipoprotein receptor-related protein (LRP). The liver is the primary target of systemic PEA, due largely to the high levels of functional LRP expressed by liver cells. Using a 3H-leucine incorporation assay to measure inhibition of protein synthesis we have demonstrated that normal (BNL CL.2) and transformed (BNL 1ME A7R.1) liver cells exhibit divergent PEA sensitivity; with BNL 1ME A7R.1 cells demonstrating greater PEA sensitivity than their non-transformed counterparts. The receptor-associated protein, a LRP antagonist, decreased PEA toxicity in BNL 1ME A7R.1 cells, confirming the importance of the LRP in PEA intoxification in this cell type. Increased PEA sensitivity in BNL 1ME A7R.1 cells was associated with increased functional cell surface LRP expression, as measured by alpha2-macroglobulin binding and internalization studies, and increased LRP mRNA levels, as determined by Northern blot analysis. Interestingly, BNL CL.2 cells were more sensitive than BNL 1ME A7R.1 cells to conjugate and mutant PEA toxins that do not utilize the LRP for cellular entry. These data demonstrate that increased LRP expression is an important mechanism by which PEA sensitivity is increased in BNL 1ME A7R.1 transformed liver cells.

Lateral root initiation in Marsilea quadrifolia. I. Origin and histogensis of lateral roots

NASA Technical Reports Server (NTRS)

Lin, B. L.; Raghavan, V.

1991-01-01

In Marsilea quadrifolia, lateral roots arise from modified single cells of the endodermis located opposite the protoxylem poles within the meristematic region of the parent root. The initial cell divides in four specific planes to establish a five-celled lateral root primordium, with a tetrahedral apical cell in the centre and the oldest merophytes and the root cap along the sides. The cells of the merophyte divide in a precise pattern to give rise to the cells of the cortex, endodermis, pericycle, and vascular tissues of the emerging lateral root. Although the construction of the parent root is more complicated than that of lateral roots, patterns of cell division and tissue formation are similar in both types of roots, with the various tissues being arranged in similar positions in relation to the central axis. Vascular connection between the lateral root primordium and the parent root is derived from the pericycle cells lying between the former and the protoxylem members of the latter. It is proposed that the central axis of the root is not only a geometric centre, but also a physiological centre which determines the fate of the different cell types.

76 FR 37136 - Post-Entry Amendment (PEA) Processing Test: Modification, Clarification, and Extension

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-24

.... Customs and Border Protection's (CBP's) Post-Entry Amendment (PEA) Processing test, which allows the...: The Post-Entry Amendment (PEA) Processing test modification set forth in this document is effective...: Background I. Post-Entry Amendment Processing Test Program The Post-Entry Amendment (PEA) Processing test...

Pea3 transcription factor promotes neurite outgrowth

PubMed Central

Kandemir, Basak; Caglayan, Berrak; Hausott, Barbara; Erdogan, Burcu; Dag, Ugur; Demir, Ozlem; Sogut, Melis S.; Klimaschewski, Lars; Kurnaz, Isil A.

2014-01-01

Pea3 subfamily of E–twenty six transcription factors consist of three major -exhibit branching morphogenesis, the function of Pea3 family in nervous system development and regeneration is only beginning to unfold. In this study, we provide evidence that Pea3 can directs neurite extension and axonal outgrowth in different model systems, and that Serine 90 is important for this function. We have also identified neurofilament-L and neurofilament-M as two putative novel targets for Pea3. PMID:25018694

Vision for Time-Varying Images

DTIC Science & Technology

2012-05-01

YOC:lbabry consisting ofSIFf feztures ( lo ~. 2004) Is constracted by rannlng k-means on :1 random set of lm:~gt:S cont21nlng examples from 211 clu.ses of...demtxlngofthed:au. Ls used to wlupllb. The p2lh from the root to a lo f ln a decisiOn tree Is a con· JUnction or loc:d deciSions on feature nJues and :as a...oomplose q..Jikelibood of oor model il pea by: N t. - los n p( ... . , ..... , .,)p(z.) •x• N • toe n p(r.~ • • r., B)p(1.18)1’(•.) . x o N

Protein-enriched pea flour extract protects stored milled rice against the rice weevil, Sitophilus oryzae

PubMed Central

Pretheep-Kumar, P.; Mohan, S.; Ramaraju, K.

2004-01-01

Studies were conducted to evaluate the effect of a protein-enriched pea (Pisum sativum var. Bonneville) flour extract against the rice weevil, Sitophilus oryzae in its repellency, toxicity, effect on fecundity, stability and sensory properties. Milled rice admixed with pea flour extract at 1% concentration significantly repelled S. oryzae. Mortality of S. oryzae was found to increase and fecundity was markedly suppressed, in rice treated with 1% pea flour extract. The toxicity and reproductive effects of the pea protein-enriched rice were found to be stable for a period of 5 months. The sensory characteristics of stored rice when eaten were not affected by the treatment with pea flour extract. This study indicates that the protein-enriched flour extract obtained from the Bonneville pea may be feasible to protect stored milled rice from insect attack. PMID:15861241

Potential alternative hosts for a powdery mildew on pea

USDA-ARS?s Scientific Manuscript database

Powdery mildew of pea (Pisum sativum) is an important disease in the field and in the greenhouse. The most widely documented powdery mildew on pea is Erysiphe pisi, but E. trifolii and E. baeumleri have also been reported. From greenhouse-grown peas, we obtained powdery mildew samples with rDNA ITS ...

Potential alternative hosts for the pea powdery mildew pathogen Erysiphe trifolii

USDA-ARS?s Scientific Manuscript database

Powdery mildew of pea (Pisum sativum) is an important disease in the field and in the greenhouse. The most widely documented powdery mildew pathogen on pea is Erysiphe pisi, but E. baeumleri and E. trifolii have also been reported. We recently showed that E. trifolii is frequently found on pea in th...

7 CFR 319.56-45 - Shelled garden peas from Kenya.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 5 2013-01-01 2013-01-01 false Shelled garden peas from Kenya. 319.56-45 Section 319.56-45 Agriculture Regulations of the Department of Agriculture (Continued) ANIMAL AND PLANT HEALTH... Shelled garden peas from Kenya. Garden peas (Pisum sativum) may be imported into the continental United...

7 CFR 319.56-45 - Shelled garden peas from Kenya.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 5 2014-01-01 2014-01-01 false Shelled garden peas from Kenya. 319.56-45 Section 319.56-45 Agriculture Regulations of the Department of Agriculture (Continued) ANIMAL AND PLANT HEALTH... Shelled garden peas from Kenya. Garden peas (Pisum sativum) may be imported into the continental United...

7 CFR 319.56-45 - Shelled garden peas from Kenya.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 5 2012-01-01 2012-01-01 false Shelled garden peas from Kenya. 319.56-45 Section 319.56-45 Agriculture Regulations of the Department of Agriculture (Continued) ANIMAL AND PLANT HEALTH... Shelled garden peas from Kenya. Garden peas (Pisum sativum) may be imported into the continental United...

7 CFR 319.56-45 - Shelled garden peas from Kenya.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 5 2011-01-01 2011-01-01 false Shelled garden peas from Kenya. 319.56-45 Section 319.56-45 Agriculture Regulations of the Department of Agriculture (Continued) ANIMAL AND PLANT HEALTH... Shelled garden peas from Kenya. Garden peas (Pisum sativum) may be imported into the continental United...

7 CFR 319.56-45 - Shelled garden peas from Kenya.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 5 2010-01-01 2010-01-01 false Shelled garden peas from Kenya. 319.56-45 Section 319... Shelled garden peas from Kenya. Garden peas (Pisum sativum) may be imported into the continental United States from Kenya only under the following conditions and in accordance with all other applicable...

Genetically modified α-amylase inhibitor peas are not specifically allergenic in mice.

PubMed

Lee, Rui-Yun; Reiner, Daniela; Dekan, Gerhard; Moore, Andrew E; Higgins, T J V; Epstein, Michelle M

2013-01-01

Weevils can devastate food legumes in developing countries, but genetically modified peas (Pisum sativum), chickpeas and cowpeas expressing the gene for alpha-amylase inhibitor-1 (αAI) from the common bean (Phaseolus vulgaris) are completely protected from weevil destruction. αAI is seed-specific, accumulated at high levels and undergoes post-translational modification as it traverses the seed endomembrane system. This modification was thought to be responsible for the reported allergenicity in mice of the transgenic pea but not the bean. Here, we observed that transgenic αAI peas, chickpeas and cowpeas as well as non-transgenic beans were all allergenic in BALB/c mice. Even consuming non-transgenic peas lacking αAI led to an anti-αAI response due to a cross-reactive response to pea lectin. Our data demonstrate that αAI transgenic peas are not more allergenic than beans or non-transgenic peas in mice. This study illustrates the importance of repeat experiments in independent laboratories and the potential for unexpected cross-reactive allergic responses upon consumption of plant products in mice.

Genetically Modified α-Amylase Inhibitor Peas Are Not Specifically Allergenic in Mice

PubMed Central

Dekan, Gerhard; Moore, Andrew E.; Higgins, T. J. V.; Epstein, Michelle M.

2013-01-01

Weevils can devastate food legumes in developing countries, but genetically modified peas (Pisum sativum), chickpeas and cowpeas expressing the gene for alpha-amylase inhibitor-1 (αAI) from the common bean (Phaseolus vulgaris) are completely protected from weevil destruction. αAI is seed-specific, accumulated at high levels and undergoes post-translational modification as it traverses the seed endomembrane system. This modification was thought to be responsible for the reported allergenicity in mice of the transgenic pea but not the bean. Here, we observed that transgenic αAI peas, chickpeas and cowpeas as well as non-transgenic beans were all allergenic in BALB/c mice. Even consuming non-transgenic peas lacking αAI led to an anti-αAI response due to a cross-reactive response to pea lectin. Our data demonstrate that αAI transgenic peas are not more allergenic than beans or non-transgenic peas in mice. This study illustrates the importance of repeat experiments in independent laboratories and the potential for unexpected cross-reactive allergic responses upon consumption of plant products in mice. PMID:23326368

Effects of beta-phenylethylamine on dopaminergic neurons of the ventral tegmental area in the rat: a combined electrophysiological and microdialysis study.

PubMed

Ishida, Kota; Murata, Mikio; Katagiri, Nobuyuki; Ishikawa, Masago; Abe, Kenji; Kato, Masatoshi; Utsunomiya, Iku; Taguchi, Kyoji

2005-08-01

The effects of systemic administration of beta-phenylethylamine (beta-PEA) and microiontophoretically applied beta-PEA on the spontaneous discharge of dopamine (DA) neurons in the ventral tegmental area (VTA) of the anesthetized rat were examined. Intravenous administration of beta-PEA (1.0, 2.5, and 5.0 mg/kg) and microiontophoretic applications of beta-PEA caused inhibitory responses in DA neurons. Systemic administration and microiontophoretic applications of beta-PEA induced dose- or current-dependent responses. The systemic beta-PEA-induced inhibitory responses were reversed by pretreatment with the DA D(2) receptor antagonists haloperidol (0.5 mg/kg i.p.) and sulpiride (10 mg/kg i.p). Pretreatment with reserpine (5 mg/kg i.p. 24 h earlier) did not completely block the systemic administration of beta-PEA (2.5 mg/kg) inhibition. A microdialysis study of freely moving rats demonstrated that the extracellular DA level increased significantly in response to local application of beta-PEA (100 muM) in the VTA via a microdialysis probe, and local application of beta-PEA-stimulated somatodendritic DA release in the VTA. The beta-PEA-induced release of DA was calcium ion-independent and was enhanced by pretreatment with pertussis toxin. These findings indicate that beta-phenylethylamine inhibits DA neuron activity via DA D(2) autoreceptors in the rat VTA and that this inhibitory effect is mediated by the somatodendritic DA release.

Growth performance and carcass and meat quality of broiler chickens fed diets containing micronized-dehulled peas (Pisum sativum cv. Spirale) as a substitute of soybean meal.

PubMed

Laudadio, V; Tufarelli, V

2010-07-01

An experiment was carried out to evaluate the effects of diets containing peas on productive traits, carcass yields, and fatty acid profiles (breast and drumstick meat) of broiler chickens. Hubbard strain broiler chicks, divided into 2 groups, received from 14 d to slaughtering age (49 d) a wheat middlings-based diet containing soybean (190 g/kg) or micronized-dehulled peas (400 g/kg) as the main protein source. The inclusion of peas did not significantly change the growth performance of birds. The pea level had no effect on the dressing percentage, the percentage of breast or drumstick muscles, and abdominal fat. The muscles of birds fed the pea diet had significant (P < 0.05) lower L* (lightness) and b* (yellowness, drumstick muscle) values and fat content. Instead, total collagen and water-holding capacity values were higher in the pea treatment. The polyunsaturated fatty acid concentration in breast and drumstick muscles was significantly increased with the alternative protein source inclusion, whereas the saturated fatty acid was similar among treatments. The n-6/n-3 polyunsaturated fatty acid ratio of the broiler drumstick meat decreased significantly in the pea group. Dietary pea inclusion improved the saturation index of meat without altering atherogenic and thrombogenic indexes. It can be concluded that the pea treatment tested had a positive effect on the performance and meat quality of broiler chickens.

Effect of the combinations between pea proteins and soluble fibres on cholesterolaemia and cholesterol metabolism in rats.

PubMed

Parolini, Cinzia; Manzini, Stefano; Busnelli, Marco; Rigamonti, Elena; Marchesi, Marta; Diani, Erika; Sirtori, Cesare R; Chiesa, Giulia

2013-10-01

Many functional foods and dietary supplements have been reported to be beneficial for the management of dyslipidaemia, one of the major risk factors for CVD. Soluble fibres and legume proteins are known to be a safe and practical approach for cholesterol reduction. The present study aimed at investigating the hypocholesterolaemic effect of the combinations of these bioactive vegetable ingredients and their possible effects on the expression of genes regulating cholesterol homeostasis. A total of six groups of twelve rats each were fed, for 28 d, Nath's hypercholesterolaemic diets, differing in protein and fibre sources, being, respectively, casein and cellulose (control), pea proteins and cellulose (pea), casein and oat fibres (oat), casein and apple pectin (pectin), pea proteins and oat fibres (pea+oat) and pea proteins and apple pectin (pea+pectin). Administration of each vegetable-containing diet was associated with lower total cholesterol concentrations compared with the control. The combinations (pea+oat and pea+pectin) were more efficacious than fibres alone in modulating cholesterolaemia ( - 53 and - 54%, respectively, at 28 d; P< 0·005). In rats fed the diets containing oat fibres or apple pectin, alone or in combination with pea proteins, a lower hepatic cholesterol content (P< 0·005) and higher hepatic mRNA concentrations of CYP7A1 and NTCP were found when compared with the control rats (P< 0·05). In summary, the dietary combinations of pea proteins and oat fibres or apple pectin are extremely effective in lowering plasma cholesterol concentrations in rats and affect cellular cholesterol homeostasis by up-regulating genes involved in hepatic cholesterol turnover.

Dopamine transporter-dependent and -independent actions of trace amine beta-phenylethylamine.

PubMed

Sotnikova, Tatyana D; Budygin, Evgeny A; Jones, Sara R; Dykstra, Linda A; Caron, Marc G; Gainetdinov, Raul R

2004-10-01

Beta-phenylethylamine (beta-PEA) is an endogenous amine that is found in trace amounts in the brain. It is believed that the locomotor-stimulating action of beta-PEA, much like amphetamine, depends on its ability to increase extracellular dopamine (DA) concentrations owing to reversal of the direction of dopamine transporter (DAT)-mediated DA transport. beta-PEA can also bind directly to the recently identified G protein-coupled receptors, but the physiological significance of this interaction is unclear. To assess the mechanism by which beta-PEA mediates its effects, we compared the neurochemical and behavioral effects of this amine in wild type (WT), heterozygous and 'null' DAT mutant mice. In microdialysis studies, beta-PEA, administered either systemically or locally via intrastriatal infusion, produced a pronounced outflow of striatal DA in WT mice whereas no increase was detected in mice lacking the DAT (DAT-KO mice). Similarly, in fast-scan voltammetry studies beta-PEA did not alter DA release and clearance rate in striatal slices from DAT-KO mice. In behavioral studies beta-PEA produced a robust but transient increase in locomotor activity in WT and heterozygous mice. In DAT-KO mice, whose locomotor activity and stereotypy are increased in a novel environment, beta-PEA (10-100 mg/kg) exerted a potent inhibitory action. At high doses, beta-PEA induced stereotypies in WT and heterozygous mice; some manifestations of stereotypy were also observed in the DAT-KO mice. These data demonstrate that the DAT is required for the striatal DA-releasing and hyperlocomotor actions of beta-PEA. The inhibitory action on hyperactivity and certain stereotypies induced by beta-PEA in DAT-KO mice indicate that targets other than the DAT are responsible for these effects.

Vicilin and convicilin are potential major allergens from pea.

PubMed

Sanchez-Monge, R; Lopez-Torrejón, G; Pascual, C Y; Varela, J; Martin-Esteban, M; Salcedo, G

2004-11-01

Allergic reactions to pea (Pisum sativum) ingestion are frequently associated with lentil allergy in the Spanish population. Vicilin have been described as a major lentil allergen. To identify the main IgE binding components from pea seeds and to study their potential cross-reactivity with lentil vicilin. A serum pool or individual sera from 18 patients with pea allergy were used to detect IgE binding proteins from pea seeds by immunodetection and immunoblot inhibition assays. Protein preparations enriched in pea vicilin were obtained by gel filtration chromatography followed by reverse-phase high-performance liquid chromatography (HPLC). IgE binding components were identified by means of N-terminal amino acid sequencing. Complete cDNAs encoding pea vicilin were isolated by PCR, using primers based on the amino acid sequence of the reactive proteins. IgE immunodetection of crude pea extracts revealed that convicilin (63 kDa), as well as vicilin (44 kDa) and one of its proteolytic fragments (32 kDa), reacted with more than 50% of the individual sera tested. Additional proteolytic subunits of vicilin (36, 16 and 13 kDa) bound IgE from approximately 20% of the sera. The lentil vicilin allergen Len c 1 strongly inhibited the IgE binding to all components mentioned above. The characterization of cDNA clones encoding pea vicilin has allowed the deduction of its complete amino acid sequence (90% of sequence identity to Len c 1), as well as those of its reactive proteolytic processed subunits. Vicilin and convicilin are potential major allergens from pea seeds. Furthermore, proteolytic fragments from vicilin are also relevant IgE binding pea components. All these proteins cross-react with the major lentil allergen Len c 1.

Factors associated with out-of-hospital cardiac arrest with pulseless electric activity: A population-based study.

PubMed

Ko, Dennis T; Qiu, Feng; Koh, Maria; Dorian, Paul; Cheskes, Sheldon; Austin, Peter C; Scales, Damon C; Wijeysundera, Harindra C; Verbeek, P Richard; Drennan, Ian; Ng, Tiffany; Tu, Jack V; Morrison, Laurie J

2016-07-01

Many patients with out-of-hospital cardiac arrest present with pulseless electric activity (PEA) rather than shockable rhythm. Despite improvements in resuscitation care, survival of PEA patients remains dismal. Our main objective was to characterize out-of-hospital cardiac arrest patients by initial presenting rhythm and to evaluate independent determinants of PEA. A population-based study was conducted using the Toronto Rescu Epistry database with linkage to administrative data in Ontario, Canada. We included patients older than 20 years who had nontraumatic cardiac arrests from 2005 to 2010. Multivariable logistic regression models were constructed to determine factors predicting the occurrence of PEA vs shockable rhythm vs asystole. Of the 9,882 included patients who received treatment, 24.5% had PEA, 26.3% had shockable rhythm, and 49.2% had asystole. Patients with PEA had a mean age of 72 years, 41.2% were female and had multiple comorbidities, and 53.4% were hospitalized in the past year. As compared with shockable rhythm, PEA patients were older, were more likely to be women, and had more comorbidities. As compared with asystole, PEA patients had similar baseline and clinical characteristics, but were substantially more likely to have an arrest witnessed by emergency medical services (odds ratio 13) or by bystander (odds ratio 3.24). Mortality at 30 days was 95.5%, 77.9%, and 98.9% for patients with PEA, shockable rhythm, asystole, respectively. Patient characteristics differed substantially in those presenting with PEA and shockable rhythm. In contrast, the main distinguishing factor between PEA and asystole cardiac arrest related mainly to factors at the time of the cardiac arrest. Copyright © 2016 Elsevier Inc. All rights reserved.

Pea Marker Database (PMD) - A new online database combining known pea (Pisum sativum L.) gene-based markers.

PubMed

Kulaeva, Olga A; Zhernakov, Aleksandr I; Afonin, Alexey M; Boikov, Sergei S; Sulima, Anton S; Tikhonovich, Igor A; Zhukov, Vladimir A

2017-01-01

Pea (Pisum sativum L.) is the oldest model object of plant genetics and one of the most agriculturally important legumes in the world. Since the pea genome has not been sequenced yet, identification of genes responsible for mutant phenotypes or desirable agricultural traits is usually performed via genetic mapping followed by candidate gene search. Such mapping is best carried out using gene-based molecular markers, as it opens the possibility for exploiting genome synteny between pea and its close relative Medicago truncatula Gaertn., possessing sequenced and annotated genome. In the last 5 years, a large number of pea gene-based molecular markers have been designed and mapped owing to the rapid evolution of "next-generation sequencing" technologies. However, the access to the complete set of markers designed worldwide is limited because the data are not uniformed and therefore hard to use. The Pea Marker Database was designed to combine the information about pea markers in a form of user-friendly and practical online tool. Version 1 (PMD1) comprises information about 2484 genic markers, including their locations in linkage groups, the sequences of corresponding pea transcripts and the names of related genes in M. truncatula. Version 2 (PMD2) is an updated version comprising 15944 pea markers in the same format with several advanced features. To test the performance of the PMD, fine mapping of pea symbiotic genes Sym13 and Sym27 in linkage groups VII and V, respectively, was carried out. The results of mapping allowed us to propose the Sen1 gene (a homologue of SEN1 gene of Lotus japonicus (Regel) K. Larsen) as the best candidate gene for Sym13, and to narrow the list of possible candidate genes for Sym27 to ten, thus proving PMD to be useful for pea gene mapping and cloning. All information contained in PMD1 and PMD2 is available at www.peamarker.arriam.ru.

How does pea architecture influence light sharing in virtual wheat–pea mixtures? A simulation study based on pea genotypes with contrasting architectures

PubMed Central

Barillot, Romain; Combes, Didier; Chevalier, Valérie; Fournier, Christian; Escobar-Gutiérrez, Abraham J.

2012-01-01

Background and aims Light interception is a key factor driving the functioning of wheat–pea intercrops. The sharing of light is related to the canopy structure, which results from the architectural parameters of the mixed species. In the present study, we characterized six contrasting pea genotypes and identified architectural parameters whose range of variability leads to various levels of light sharing within virtual wheat–pea mixtures. Methodology Virtual plants were derived from magnetic digitizations performed during the growing cycle in a greenhouse experiment. Plant mock-ups were used as inputs of a radiative transfer model in order to estimate light interception in virtual wheat–pea mixtures. The turbid medium approach, extended to well-mixed canopies, was used as a framework for assessing the effects of leaf area index (LAI) and mean leaf inclination on light sharing. Principal results Three groups of pea genotypes were distinguished: (i) early and leafy cultivars, (ii) late semi-leafless cultivars and (iii) low-development semi-leafless cultivars. Within open canopies, light sharing was well described by the turbid medium approach and was therefore determined by the architectural parameters that composed LAI and foliage inclination. When canopy closure started, the turbid medium approach was unable to properly infer light partitioning because of the vertical structure of the canopy. This was related to the architectural parameters that determine the height of pea genotypes. Light capture was therefore affected by the development of leaflets, number of branches and phytomers, as well as internode length. Conclusions This study provides information on pea architecture and identifies parameters whose variability can be used to drive light sharing within wheat–pea mixtures. These results could be used to build up the architecture of pea ideotypes adapted to multi-specific stands towards light competition. PMID:23240074

THE ORIGIN AND OPTICAL DEPTH OF IONIZING RADIATION IN THE 'GREEN PEA' GALAXIES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jaskot, A. E.; Oey, M. S.

2013-04-01

Although Lyman-continuum (LyC) radiation from star-forming galaxies likely drove the reionization of the universe, observations of star-forming galaxies at low redshift generally indicate low LyC escape fractions. However, the extreme [O III]/[O II] ratios of the z = 0.1-0.3 Green Pea galaxies may be due to high escape fractions of ionizing radiation. To analyze the LyC optical depths and ionizing sources of these rare, compact starbursts, we compare nebular photoionization and stellar population models with observed emission lines in the Peas' Sloan Digital Sky Survey (SDSS) spectra. We focus on the six most extreme Green Peas, the galaxies with themore » highest [O III]/[O II] ratios and the best candidates for escaping ionizing radiation. The Balmer line equivalent widths and He I {lambda}3819 emission in the extreme Peas support young ages of 3-5 Myr, and He II {lambda}4686 emission in five extreme Peas signals the presence of hard ionizing sources. Ionization by active galactic nuclei or high-mass X-ray binaries is inconsistent with the Peas' line ratios and ages. Although stacked spectra reveal no Wolf-Rayet (WR) features, we tentatively detect WR features in the SDSS spectra of three extreme Peas. Based on the Peas' ages and line ratios, we find that WR stars, chemically homogeneous O stars, or shocks could produce the observed He II emission. If hot stars are responsible, then the Peas' optical depths are ambiguous. However, accounting for emission from shocks lowers the inferred optical depth and suggests that the Peas may be optically thin. The Peas' ages likely optimize the escape of LyC radiation; they are old enough for supernovae and stellar winds to reshape the interstellar medium, but young enough to possess large numbers of UV-luminous O or WR stars.« less

The microstructure and fracture behavior of the dissimilar alloy 690-SUS 304L joint with various Nb addition

NASA Astrophysics Data System (ADS)

Lee, H. T.; Jeng, S. L.; Kuo, T. Y.

2003-05-01

This study investigates the microstructure and fracture behavior of dissimilar weldments of alloy 690 and SUS 304L for various additions of niobium (0.1, 1.03, 2.49, and 3.35 wt pct) in the flux. With identical parameters and procedures, weldments were butt welded by the shielding metal arc welding (SMAW) process using three layers, with each layer being deposited in a single pass. The results indicate that the microstructure of the fusion zone was primarily dendritic and that the contents of Ni, Cr, and Fe within this zone remain relatively constant and resemble alloy 690. With Nb addition, it is noted that the microstructure changes from a cellular to columnar dendrite and equiaxed dendrite. Meanwhile, the dendrite arm spacing reduces and the secondary arms grow longer. Moreover, the composition of the interdendritic phase, whose precipitate volume percentage increases from 5 to 25 pct, changes from Al-Ti-O to Nb rich. The spread of the interdendritic phase is less in the root bead than in the cap bead due to the greater influence of base metal dilution in this region. Mechanical tests indicate that Nb addition increases the average hardness of the weldment and reduces its elongation prior to rupture. However, the tensile strength is essentially unchanged by Nb addition. It is found that the average hardness of the root bead is generally lower than the cap bead, and that the tensile specimens all rupture in the fusion zone, with the fracture surfaces exhibiting ductile features. It is noted that the cap bead tends to rupture interdendritically with increasing Nb addition. Finally, fractography shows that the dimples in the root become larger and shallower with Nb addition and are rich with an interdendritic phase.

Analgesic effects of β-phenylethylamine and various methylated derivatives in mice.

PubMed

Mosnaim, Aron D; Hudzik, Thomas; Wolf, Marion E

2014-09-01

Administration of β-phenylethylamine (PEA), the simplest endogenous neuroamine, and various methylated PEA derivatives including α-methyl PEA (amphetamine, AMP) elicits analgesia in mice. Five or 20 min after intraperitoneal PEA injection of as little as 6 mg/kg resulted in an increased latency response time (from 2.4 ± 0.4 to 8.5 ± 2.3 or 7.0 ± 3.0 s, respectively) to the thermal stimulus (hot-plate test), which reached statistical significance at the 15 mg/kg (20 min; 13.1 ± 0.4 s) or 25 mg/kg dose (5 min; 15.3 ± 4.1 s). This PEA effect, was dose-dependent (albeit non-linear: 6, 12, 15, 25, 50 and 100 mg/kg), reached the cut-off time of 45 s at the upper PEA dose (5 min), and it was consistently enhanced by pretreatment with the monoamine oxidase inhibitor pargyline (P). Methylated PEA derivatives (15 and 100 mg/kg dose) produced various degrees of analgesia (in decreasing order p-Me PEA > PEA > N,N-diMe PEA > N-Me PEA) which, likewise to PEA itself, were consistently increased by P and declined over time (mice tested 5, 20 and 60 min after amine injection); small but statistically significant o- and β-Me PEA antinociceptive effects (5 min) were observed only at the higher dose (in the presence of P for β-Me PEA). A small analgesic effect was observed after the administration of AMP (5 or 10 mg/kg) which failed, even after P, to reach statistically significance. Independent of the amine and concentration tested, individual compound's antinociceptive properties were reliably increased by P (exception of AMP), decreased by reserpine (R) or haloperidol (H), and remained essentially unchanged after naloxone (N) administration suggesting the involvement of catecholamines, but not opioid peptides, in their observed analgesic effects. Injection of P + N produced results similar to those seen after P alone. Under the experimental conditions described neither P, R, H or N had any effects by themselves. These findings suggest additional understanding of the mechanism of action responsible for the analgesic effects of these amines would be of interest, leading further to controlled studies on their alleged usefulness as weight reducing agents and sport performance enhancers.

Native Grasses as a Management Alternative on Vegetated Closure Caps

NASA Astrophysics Data System (ADS)

Kwit, Charles; Collins, Beverly

2008-06-01

Capped waste sites often are vegetated with commercial turf grasses to increase evapotranspiration and prevent erosion and possible exposure of the barrier. Fertilizer, frequent watering, and mowing may be required to establish the turf grass and prevent invasion by trees and shrubs. Oldfield vegetation of grasses and forbs is a possible sustainable alternative to turf grass communities. To determine if oldfield vegetation can establish on caps, we (1) compared establishment of a dominant oldfield grass and a commercial turf grass under different combinations of new closure cap management: spring or summer planting and presence or absence of amendments to alleviate drought (watering, mulch) or increase soil fertility (fertilizer, lime, a nitrogen-fixing legume); (2) surveyed existing caps to determine if oldfield species establish naturally; and (3) performed a greenhouse experiment to compare growth of two native grasses under low and amended (added water, soil nutrients) conditions. Both the commercial grass and oldfield species established under new cap conditions; fertilizer, water, and mulch improved vegetation establishment in spring or summer, but legumes decreased grass cover. In the greenhouse, both native grasses grew best with amendments; however, substantial stem and root length were obtained with no fertilizer and only once-weekly watering. Existing vegetated caps supported planted grasses and naturally established oldfield species. Overall, the results indicate native grasses can establish on new caps and oldfields can serve as a management model; further work is needed to determine the management strategy to maintain herbaceous vegetation and slow woody species invasion.

Feeding value of field pea as a protein source in forage-based diets fed to beef cattle.

PubMed

Soto-Navarro, S A; Encinias, A M; Bauer, M L; Lardy, G P; Caton, J S

2012-02-01

Three studies were conducted to evaluate the feasibility of field peas as a protein source in diets for beef cattle. In the first study, 4 cultivars of field pea were incubated in situ to determine rate and extent of CP disappearance. Results indicate that field pea cultivars vary in CP content (22.6, 26.1, 22.6, and 19.4%, DM basis for Profi, Arvika, Carneval, and Trapper, respectively). Soluble protein fraction ranged from 34.9% for Trapper to 54.9% for Profi. Degradable CP fraction was greater (P = 0.01) for Trapper compared with the other cultivars, and no differences (P ≥ 0.25) were observed among Profi, Arvika, and Carneval. Rate of CP degradation differed (P ≤ 0.03) for all cultivars, with Profi being the greatest and Trapper the smallest (10.8, 10.0, 8.1, and 6.3 ± 1.4%/h for Profi, Carneval, Arvika, and Trapper, respectively). Estimated RDP was not different (P = 0.21) for all 4 cultivars. In the second study, 30 crossbred beef steers (301 ± 15 kg) were individually fed and used to evaluate effects of field pea processing (whole, rolled, or ground) on steer performance. Diets contained 40% field pea grain. Growing steers consuming whole field pea had greater ADG (P = 0.08) than those consuming processed field pea (1.69, 1.52, and 1.63 ± 0.05 kg/d, for whole, rolled, and ground, respectively). However, DMI (kg/d and as % of BW) and G:F were not different (P ≥ 0.24). In the third study, 35 individually fed gestating beef cows (694 ± 17 kg) were used to evaluate the use of field pea as a protein supplement for medium quality grass hay (9.3% CP). Treatments consisted of whole field peas at 1) 0 g (CON), 2) 680 g (FP680), 3) 1,360 g (FP1360), and 4) 2,040 g (FP2040), and 5) 1,360 g of 74% barley and 26% canola meal (BCM). Total intake (forage + supplement) of gestating beef cows increased with increasing field pea level (linear, P = 0.01; supplemented vs. nonsupplemented, P = 0.01). In summary, protein quantity and rate of ruminal protein degradation vary across sources of field peas used in this study. Additionally, because of source variability, nutrient analysis and animal requirements should be considered when field pea is incorporated into beef cattle diets. Processing field pea does not improve performance of growing steers. Supplementation of field pea to gestating cows consuming medium-quality grass hay increased total DMI. Overall, our data indicate field pea can be used in a wide variety of beef cattle diets.

Primary epiploic appendagitis and successful outpatient management

PubMed Central

Schnedl, Wolfgang J.; Krause, Robert; Wallner-Liebmann, Sandra J.; Tafeit, Erwin; Mangge, Harald; Tillich, Manfred

2012-01-01

Summary Background Primary epiploic appendagitis (PEA) is a rare cause of abdominal acute or subacute complaints. Diagnosis of PEA is made with ultrasonography (US) or when computed tomography (CT) reveals a characteristic lesion. Case Report We report on two patients with PEA. In one patient PEA was first seen with US and confirmed with contrast enhanced CT, and in the second patient CT without contrast enhancement demonstrated PEA. In both patients an outpatient recovery with conservative non-surgical treatment is described. Conclusions Medical personnel should be aware of this rare disease, which mimics many other intra-abdominal acute and subacute conditions. A correct diagnosis of PEA with imaging procedures enables conservative and successful outpatient management avoiding unnecessary surgical intervention and additional costs. PMID:22648258

Capping a Pulpotomy with Calcium Aluminosilicate Cement: Comparison to Mineral Trioxide Aggregates

PubMed Central

Kramer, Phillip R.; Woodmansey, Karl F.; White, Robert; Primus, Carolyn M.; Opperman, Lynne A.

2014-01-01

Introduction Calcium aluminate cements have shown little affinity for bacterial growth, low toxicity, and immunogenicity when used as a restoration material, but calcium aluminate cements have not been tested in vivo in pulpotomy procedures. Methods To address this question, a calcium aluminate cement (Quick-Set) was tested along with 2 mineral trioxide aggregates, ProRoot MTA and MTA Plus. These cements were used as a capping agent after pulpotomy. Control rats had no pulpotomy, or the pulpotomy was not capped. Proinflammatory cytokines interleukin (IL)-1β and IL-1α were measured, and histology was performed at 30 and 60 days after capping. The nociceptive response was determined by measuring the lengthening of the rat's meal duration. Results and Conclusions: IL-1β and IL-1α concentrations were reduced in the capped teeth, but no differences were observed among the 3 cements. Dentinal bridging could be detected at both 30 and 60 days with each of the 3 cements, and the pulps were still vital 60 days after capping. Meal duration significantly shortened after placement of the 3 different cements, indicating a nociceptive response, but there were no differences among the materials. Calcium aluminate cements had similar properties to mineral trioxide aggregates and is a viable option for pulpotomy procedures. PMID:25146026

Managed pollinator CAP Coordinated Agricultural Project

USDA-ARS?s Scientific Manuscript database

Scientists are looking at the root cause of the Colony Collapse Disorder (CCD) syndrome; searching for new diseases, harmful chemicals or a combination of these factors which could inflict stress on bee colonies pushing them over the edge for recovery. Among multiple suspects identified so far, bee...

Life Cycle, Pathogenicity, Histopathology, and Host Range of Race 5 of the Barley Root-Knot Nematode

PubMed Central

Ediz, Söngul A.; Dickerson, O. J.

1976-01-01

The optimum temperature for development of race 5 of Meloidogyne naasi was 26 C. A life cycle was completed in 34 days. Growth of sorghum was suppressed when inoculated with M. naasi. Observations of M. naasi-infected sorghum roots demonstrated that roots were penetrated just behind the root cap; giant cells were generally initiated either in the procambial region or in very young phloem. When giant cells developed in the cortex, corresponding areas of the vascular system did not have an endodermis, pericycle, or phloem fibers. Nineteen plant species were tested for suitability as hosts for race 5 of M. naasi. Reproduction occurred on 11 of 12 monocotolydenous hosts and none of 7 dicotolydenous hosts. Reproduction often occurred without gall development. PMID:19308227

Bean α-amylase inhibitor 1 in transgenic peas (Pisum sativum) provides complete protection from pea weevil (Bruchus pisorum) under field conditions

PubMed Central

Morton, Roger L.; Schroeder, Hart E.; Bateman, Kaye S.; Chrispeels, Maarten J.; Armstrong, Eric; Higgins, Thomas J. V.

2000-01-01

Two α-amylase inhibitors, called αAI-1 and αAI-2, that share 78% amino acid sequence identity and have a differential specificity toward mammalian and insect α-amylases are present in different accessions of the common bean (Phaseolus vulgaris). Using greenhouse-grown transgenic peas (Pisum sativum), we have shown previously that expression of αAI-1 in pea seeds can provide complete protection against the pea weevil (Bruchus pisorum). Here, we report that αAI-1 also protects peas from the weevil under field conditions. The high degree of protection is explained by our finding that αAI-1 inhibits pea bruchid α-amylase by 80% over a broad pH range (pH 4.5–6.5). αAI-2, on the other hand, is a much less effective inhibitor of pea bruchid α-amylase, inhibiting the enzyme by only 40%, and only in the pH 4.0–4.5 range. Nevertheless, this inhibitor was still partially effective in protecting field-grown transgenic peas against pea weevils. The primary effect of αAI-2 appeared to be a delay in the maturation of the larvae. This contrasts with the effect of αAI-1, which results in larval mortality at the first or second instar. These results are discussed in relationship to the use of amylase inhibitors with different specificities to bring about protection of crops from their insect pests or to decrease insect pest populations below the economic injury level. PMID:10759552

Amphetamine Potentiates the Effects of β-Phenylethylamine through Activation of an Amine-Gated Chloride Channel

PubMed Central

Safratowich, Bryan D.; Hossain, Murad; Bianchi, Laura

2014-01-01

β-Phenylethylamine (βPEA) is a trace amine present in the CNS of all animals tested to date. However, its function is still not fully understood. βPEA has been suggested to function as a neurotransmitter and/or to mimic the effect of amphetamine (Amph). In support of the latter is the observation that βPEA and Amph produce similar but not identical behaviors. Here, we show that βPEA, like Amph, activates the dopamine transporter and the amine-gated chloride channel LGC-55 to generate behaviors in Caenorhabditis elegans. However, although Amph-induced behaviors occurred gradually during 10 min of treatment, βPEA induced maximal effects within 1 min. In vitro data demonstrate that βPEA activates the LGC-55 more efficiently than Amph (Km = 9 and 152 μm, respectively) and generates saturating currents that are 10 times larger than those produced by Amph. These results suggest that activation of LGC-55 mostly accounts for the behavioral effects reached after 1 min of treatment with βPEA. Importantly, our in vitro and in vivo data show that Amph increases the effects induced by βPEA on the LGC-55, indicating that Amph potentiates the effects generated by the biogenic amine βPEA. Together, our data not only identify a new target for βPEA, but also offer a novel mechanism of action of Amph. In addition, our results highlight C. elegans as a powerful genetic model for studying the effects of biogenic and synthetic amines both at the molecular and behavioral levels. PMID:24672014

Amphetamine potentiates the effects of β-phenylethylamine through activation of an amine-gated chloride channel.

PubMed

Safratowich, Bryan D; Hossain, Murad; Bianchi, Laura; Carvelli, Lucia

2014-03-26

β-Phenylethylamine (βPEA) is a trace amine present in the CNS of all animals tested to date. However, its function is still not fully understood. βPEA has been suggested to function as a neurotransmitter and/or to mimic the effect of amphetamine (Amph). In support of the latter is the observation that βPEA and Amph produce similar but not identical behaviors. Here, we show that βPEA, like Amph, activates the dopamine transporter and the amine-gated chloride channel LGC-55 to generate behaviors in Caenorhabditis elegans. However, although Amph-induced behaviors occurred gradually during 10 min of treatment, βPEA induced maximal effects within 1 min. In vitro data demonstrate that βPEA activates the LGC-55 more efficiently than Amph (Km = 9 and 152 μm, respectively) and generates saturating currents that are 10 times larger than those produced by Amph. These results suggest that activation of LGC-55 mostly accounts for the behavioral effects reached after 1 min of treatment with βPEA. Importantly, our in vitro and in vivo data show that Amph increases the effects induced by βPEA on the LGC-55, indicating that Amph potentiates the effects generated by the biogenic amine βPEA. Together, our data not only identify a new target for βPEA, but also offer a novel mechanism of action of Amph. In addition, our results highlight C. elegans as a powerful genetic model for studying the effects of biogenic and synthetic amines both at the molecular and behavioral levels.

The effect of olfactory training on the odor threshold in patients with traumatic anosmia.

PubMed

Jiang, Rong-San; Twu, Chih-Wen; Liang, Kai-Li

2017-09-01

Olfactory training is a novel intervention that has been used to treat olfactory dysfunction. This study attempted to investigate the effect of olfactory training in patients with traumatic anosmia. Patients with a clear history of anosmia after experiencing a head injury and whose phenyl ethyl alcohol (PEA) odor detection thresholds were -1 after steroid and zinc treatment were included. The patients were randomly divided into two groups, with patients in one group given a bottle of PEA and those in another group given a bottle of mineral oil for 3-month olfactory training. All the patients were followed up with a PEA threshold test and the traditional Chinese version of the University of Pennsylvania Smell Identification Test (UPSIT-TC). Magnetic resonance imaging was performed to measure the volume of the olfactory bulbs. Any patient whose PEA threshold result was below -1.01 or whose UPSIT-TC score increased four or more points was considered to have shown improvement in their olfactory function. Forty-two patients received PEA olfactory training, whereas 39 received olfactory training with mineral oil. The improvement of PEA thresholds function was observed in 10 patients within the PEA group and in 2 patients in the mineral oil group. The frequency of improvement of threshold within the PEA group was significantly higher than that of the mineral oil group. Neither olfactory bulb volume nor UPSIT-TC score was significantly different between the two groups. Our results showed that olfactory training with PEA can improve PEA odor threshold levels in patients with traumatic anosmia.

Fibril formation from pea protein and subsequent gel formation.

PubMed

Munialo, Claire Darizu; Martin, Anneke H; van der Linden, Erik; de Jongh, Harmen H J

2014-03-19

The objective of this study was to characterize fibrillar aggregates made using pea proteins, to assemble formed fibrils into protein-based gels, and to study the rheological behavior of these gels. Micrometer-long fibrillar aggregates were observed after pea protein solutions had been heated for 20 h at pH 2.0. Following heating of pea proteins, it was observed that all of the proteins were hydrolyzed into peptides and that 50% of these peptides were assembled into fibrils. Changes on a structural level in pea proteins were studied using circular dichroism, transmission electron microscopy, and particle size analysis. During the fibril assembly process, an increase in aggregate size was observed, which coincided with an increase in thioflavin T binding, indicating the presence of β-sheet aggregates. Fibrils made using pea proteins were more branched and curly. Gel formation of preformed fibrils was induced by slow acidification from pH 7.0 to a final pH of around pH 5.0. The ability of pea protein-based fibrillar gels to fracture during an amplitude sweep was comparable to those of soy protein and whey protein-based fibrillar gels, although gels prepared from fibrils made using pea protein and soy protein were weaker than those of whey protein. The findings show that fibrils can be prepared from pea protein, which can be incorporated into protein-based fibrillar gels.

2-Phenylethylamine in combination with l-deprenyl lowers the striatal level of dopamine and prolongs the duration of the stereotypy in mice.

PubMed

Kitanaka, Junichi; Kitanaka, Nobue; Tatsuta, Tomohiro; Takemura, Motohiko

2005-11-01

2-Phenylethylamine (PEA)-induced stereotypy in rodents is suggested to model psychotic symptoms of schizophrenia. It is reported that PEA induces dopamine release in the striatum in vivo and in vitro. The present study analyzed the PEA-induced stereotypy and possible associated brain dopamine metabolism in mice. Using male ICR mice treated with a combination of PEA (100 mg/kg, i.p.) and increasing doses of l-deprenyl (0-10 mg/kg, s.c.), we examined (1) the behavioral profile of stereotypy (rating the scores), and (2) the tissue levels of dopamine and its metabolites by high-performance liquid chromatography. The stereotypic scores reached a plateau level at 10 min which lasted until 30 min after a single administration of 100 mg/kg PEA. The stereotyped behavior completely disappeared 45 min after PEA administration. Pretreatment with l-deprenyl (0.1, 1, and 10 mg/kg, s.c.) dose-dependently prolonged the duration of PEA-induced stereotypy. Notably, pretreatment with l-deprenyl dose-dependently increased the continuous sniffing. Treatment with PEA in combination of l-deprenyl (1 and 10 mg/kg) significantly reduced the level of dopamine in the region of the striatum and nucleus accumbens, compared with control animals. These results suggest that PEA in combination with l-deprenyl prolonged the duration of the stereotypy (particularly, continuous sniffing) while reducing the striatal level of dopamine.

Palmitoylethanolamide, a Natural Retinoprotectant: Its Putative Relevance for the Treatment of Glaucoma and Diabetic Retinopathy

PubMed Central

Keppel Hesselink, Jan M.; Costagliola, Ciro; Fakhry, Josiane; Kopsky, David J.

2015-01-01

Retinopathy is a threat to the eyesight, and glaucoma and diabetes are the main causes for the damage of retinal cells. Recent insights pointed out a common pathogenetic pathway for both disorders, based on chronic inflammation. Palmitoylethanolamide (PEA) is an endogenous cell protective lipid. Since its discovery in 1957 as a biologically active component in foods and in many living organisms, around 500 scientific papers have been published on PEA's anti-inflammatory and neuron-protective properties. PEA has been evaluated for glaucoma, diabetic retinopathy, and uveitis, pathological states based on chronic inflammation, respiratory disorders, and various pain syndromes in a number of clinical trials since the 70s of 20th century. PEA is available as a food supplement (PeaPure) and as diet food for medical purposes in Italy (Normast, PeaVera, and Visimast). These products are notified in Italy for the nutritional support in glaucoma and neuroinflammation. PEA has been tested in at least 9 double blind placebo controlled studies, among which two studies were in glaucoma, and found to be safe and effective up to 1.8 g/day, with excellent tolerability. PEA therefore holds a promise in the treatment of a number of retinopathies. We discuss PEA as a putative anti-inflammatory and retinoprotectant compound in the treatment of retinopathies, especially related to glaucoma and diabetes. PMID:26664738

Doing the Basics Better in Africa: How School Support, Autonomy, and Accountability Improved Outcomes for Girls in PEAS Schools

ERIC Educational Resources Information Center

Hills, Libby

2017-01-01

Promoting Equality in African Schools (PEAS) seeks to expand access to sustainably delivered, quality secondary education in Africa. PEAS builds and runs chains of not-for-profit, low-cost private schools in public-private partnership with governments. External evaluation data show that PEAS schools in Uganda are delivering higher quality…

Large-scale evaluation of pea (Pisum sativum L.) germplasm for cold tolerance in the open field during winter in Qingdao.

USDA-ARS?s Scientific Manuscript database

As a cool season crop, pea (Pisum sativum L.) can tolerate frost at the vegetative stage but has yield loss when freezing stress occurs at reproductive stage. Cold tolerance improvement of pea varieties is important for the stable yield and the expansion of winter pea planting area. Under the natura...

Germinated Pigeon Pea (Cajanus cajan): a novel diet for lowering oxidative stress and hyperglycemia.

PubMed

Uchegbu, Nneka N; Ishiwu, Charles N

2016-09-01

This work studied the antioxidant activity of extract of germinated pigeon pea (Cajanus cajan) in alloxan-induced diabetic rats. Germination was carried out in a dark chamber under room temperature (28°C). The total phenolic, 1,1,diphenyl-2-picrylhy-drazyl free radical (DPPH) scavenging, the inhibition of α-amylase and α-glucosidase were done in vitro and blood glucose levels of the animal were investigated. Lipid peroxidation (LPO) and reduced glutathione (GSH) were analyzed spectrophotometrically. The total phenolic and DPPH scavenging activity increased by 30% and 63%, respectively, after germinating pigeon pea. Also after germination there was an increase in the inhibitory potential of pigeon pea extract against α-glucosidase compared with the nongerminated pigeon pea extract. There was a significant increase (P < 0.05) in fasting blood glucose level of alloxan-induced rats. Consumption of germinated pigeon pea extract gave rise to a reduced fasting blood glucose level in diabetic rats. On administration of germinated pigeon pea extract, LPO reduced drastically but there was an increase in the level of GSH. This study concluded that intake of germinated pigeon pea is a good dietary supplement for controlling hyperglycemia and LPO.

A novel plasmid pEA68 of Erwinia amylovora and the description of a new family of plasmids.

PubMed

Ismail, Emadeldeen; Blom, Jochen; Bultreys, Alain; Ivanović, Milan; Obradović, Aleksa; van Doorn, Joop; Bergsma-Vlami, Maria; Maes, Martine; Willems, Anne; Duffy, Brion; Stockwell, Virginia O; Smits, Theo H M; Puławska, Joanna

2014-12-01

Recent genome analysis of Erwinia amylovora, the causal agent of fire blight disease on Rosaceae, has shown that the chromosome is highly conserved among strains and that plasmids are the principal source of genomic diversity. A new circular plasmid, pEA68, was found in E. amylovora strain 692 (LMG 28361), isolated in Poland from Sorbus (mountain ash) with fire blight symptoms. Annotation of the 68,763-bp IncFIIa-type plasmid revealed that it contains 79 predicted CDS, among which two operons (tra, pil) are associated with mobility. The plasmid is maintained stably in E. amylovora and does not possess genes associated with antibiotic resistance or known virulence genes. Curing E. amylovora strain 692 of pEA68 did not influence its virulence in apple shoots nor amylovoran synthesis. Of 488 strains of E. amylovora from seventeen countries, pEA68 was only found in two additional strains from Belgium. Although the spread of pEA68 is currently limited to Europe, pEA68 comprises, together with pEA72 and pEA78 both found in North America, a new plasmid family that spans two continents.

Effects of Phenethyl Alcohol on Phospholipid Metabolism in Escherichia coli

PubMed Central

Nunn, William D.; Tropp, Burton E.

1972-01-01

The incorporation of labeled precursors into the deoxyribonucleic acid, ribonucleic acid (RNA), proteins, and phospholipids of Escherichia coli cultured in the presence of phenethyl alcohol (PEA) was determined. PEA inhibited the uptake of labeled uracil to the same extent in cells exhibiting relaxed and stringent control of RNA synthesis. This indicates that PEA does not primarily affect amino acid synthesis or activation. Uptake of labeled acetate into the phospholipid fraction was more sensitive to inhibition by low concentrations of PEA than was the uptake of labeled precursors into the macromolecules. Thymine starvation or the addition of nalidixic acid (10 μg/ml) had no effect on acetate incorporation. Chloramphenicol (25 μg/ml) was a much less effective inhibitor of acetate incorporation than was PEA. The distribution of labeled acetate incorporated into phospholipids was markedly affected by the presence of PEA. The uptake of acetate into phosphatidylethanolamine and phosphatidylglycerol was inhibited, whereas the uptake of acetate into the cardiolipin fraction was unaffected. Since acetate incorporation into phospholipid was quite sensitive to PEA, we suggest that the PEA-sensitive component required for the initiation of replication may be a phospholipid(s). PMID:4550658

Influences of pea morphology and interacting factors on pea aphid (Homoptera: Aphididae) reproduction.

PubMed

Buchman, N; Cuddington, K

2009-08-01

It has been claimed that plant architecture can alter aphid reproductive rates, but the mechanism driving this effect has not been identified. We studied interactions between plant architecture, aphid density, environmental conditions, and nutrient availability on the reproduction of pea aphids [Acyrthosiphon pisum (Harris)] using four near-isogenic peas (Pisum sativum L.) that differ in morphology. Manipulations of aphid density (1, 5, and 10 adults per plant) allowed us to examine any effects of plant morphology on crowding and consequently reproduction. Pea morphology per se did not alter pea aphid crowding, as measured by mean nearest neighbor distance, and there was no effect on reproduction. In addition, reproduction increased with increasing adult density, indicating positive density dependence. In a separate experiment, peas were fertilized to determine whether differences between nutrient availability of the four different morphologies might drive any observed differences in aphid reproduction. Although plant nitrogen content was altered by fertilization treatments, this did not have an impact on aphid reproduction. Greenhouse experiments, however, suggested that pea morphology can interact with environmental conditions to reduce aphid reproduction under some conditions. We conclude that plant morphology only influences aphid reproduction when environmental conditions are less than optimal.

Antioxidation, angiotensin converting enzyme inhibition activity, nattokinase, and antihypertension of Bacillus subtilis (natto)-fermented pigeon pea.

PubMed

Lee, Bao-Hong; Lai, Yi-Syuan; Wu, She-Ching

2015-12-01

Because of the high incidence of cardiovascular diseases in Asian countries, traditional fermented foods from Asia have been increasingly investigated for antiatherosclerotic effects. This study investigated the production of nattokinase, a serine fibrinolytic enzyme, in pigeon pea by Bacillus subtilis fermentation. B. subtilis 14714, B. subtilis 14715, B. subtilis 14716, and B. subtilis 14718 were employed to produce nattokinase. The highest nattokinase activity in pigeon pea was obtained using B. subtilis 14715 fermentation for 32 hours. In addition, the levels of antioxidants (phenolics and flavonoids) and angiotensin converting enzyme inhibitory activity were increased in B. subtilis 14715-fermented pigeon pea, compared with those in nonfermented pigeon pea. In an animal model, we found that both water extracts of pigeon pea (100 mg/kg body weight) and water extracts of B. subtilis-fermented pigeon pea (100 mg/kg body weight) significantly improved systolic blood pressure (21 mmHg) and diastolic blood pressure (30 mmHg) in spontaneously hypertensive rats. These results suggest that Bacillus-fermented pigeon pea has benefits for cardiovascular health and can be developed as a new dietary supplement or functional food that prevents hypertension. Copyright © 2015. Published by Elsevier B.V.

Root gravitropism

NASA Technical Reports Server (NTRS)

Masson, P. H.

1995-01-01

When a plant root is reoriented within the gravity field, it responds by initiating a curvature which eventually results in vertical growth. Gravity sensing occurs primarily in the root tip. It may involve amyloplast sedimentation in the columella cells of the root cap, or the detection of forces exerted by the mass of the protoplast on opposite sides of its cell wall. Gravisensing activates a signal transduction cascade which results in the asymmetric redistribution of auxin and apoplastic Ca2+ across the root tip, with accumulation at the bottom side. The resulting lateral asymmetry in Ca2+ and auxin concentration is probably transmitted to the elongation zone where differential cellular elongation occurs until the tip resumes vertical growth. The Cholodny-Went theory proposes that gravity-induced auxin redistribution across a gravistimulated plant organ is responsible for the gravitropic response. However, recent data indicate that the gravity-induced reorientation is more complex, involving both auxin gradient-dependent and auxin gradient-independent events.

Expression of bone morphogenetic proteins and Msx genes during root formation.

PubMed

Yamashiro, T; Tummers, M; Thesleff, I

2003-03-01

Like crown development, root formation is also regulated by interactions between epithelial and mesenchymml tissues. Bone morphogenetic proteins (BMPs), together with the transcription factors Msx1 and Msx2, play important roles in these interactions during early tooth morphogenesis. To investigate the involvement of this signaling pathway in root development, we analyzed the expression patterns of Bmp2, Bmp3, Bmp4, and Bmp7 as well as Msx1 and Msx2 in the roots of mouse molars. Bmp4 was expressed in the apical mesenchyme and Msx2 in the root sheath. However, Bmps were not detected in the root sheath epithelium, and Msx transcripts were absent from the underlying mesenchyme. These findings indicate that this Bmp signaling pathway, required for tooth initiation, does not regulate root development, but we suggest that root shape may be regulated by a mechanism similar to that regulating crown shape in cap-stage tooth germs. Msx2 expression continued in the epithelial cell rests of Malassez, and the nearby cementoblasts intensely expressed Bmp3, which may regulate some functions of the fragmented epithelium.

The initiation of lateral roots in the primary roots of maize (Zea mays L.) implies a reactivation of cell proliferation in a group of founder pericycle cells.

PubMed

Alarcón, M Victoria; Lloret, Pedro G; Martín-Partido, Gervasio; Salguero, Julio

2016-03-15

The initiation of lateral roots (LRs) has generally been viewed as a reactivation of proliferative activity in pericycle cells that are committed to initiate primordia. However, it is also possible that pericycle founder cells that initiate LRs never cease proliferative activity but rather are displaced to the most distal root zones while undertaking successive stages of LR initiation. In this study, we tested these two alternative hypotheses by examining the incorporation of 5-bromo-2'-deoxyuridine (BrdU) into the DNA of meristematic root cells of Zea mays. According to the values for the length of the cell cycle and values for cell displacement along the maize root, our results strongly suggest that pericycle cells that initiate LR primordia ceased proliferative activity upon exiting the meristematic zone. This finding is supported by the existence of a root zone between 4 and 20mm from the root cap junction, in which neither mitotic cells nor labelled nuclei were observed in phloem pericycle cells. Copyright © 2016 Elsevier GmbH. All rights reserved.

Capping hazardous red mud using acidic soil with an embedded layer of zeolite for plant growth.

PubMed

Ma, Yingqun; Si, Chunhua; Lin, Chuxia

2014-01-01

A nearly three-year microcosm experiment was conducted to test the effectiveness of capping red mud using acidic soil with an embedded layer of zeolite in sustaining the growth of a grass species. This 'sandwich-structured' design allowed self-sustaining growth of the plants under rain-fed conditions no matter whether the underlying red mud was neutralized or not. During the initial stage, the plants grew better when the red mud was not neutralized with MgCl2 probably due to pH rise in the root zone. Neutralization of red mud led to salinization and pH decrease in the root zone. However, the difference in plant growth performance between these scenarios became less remarkable over time due to gradual improvement of soil conditions in the neutralized scenarios. Continuous leaching of soluble salts and alkali by rainwater extended the root zone to the red mud layer. As a result of vegetative production, soil organic matter rapidly accumulated. This, combined with increase in pH and decrease in salinity, markedly facilitated microbial activities and consequently improved the supply of nutrients. This study provides abasis for field-scale experimental design that will have implications for effectively establishing vegetative cover in red mud disposal sites to control dust hazards.

Trichoderma-Induced Acidification Is an Early Trigger for Changes in Arabidopsis Root Growth and Determines Fungal Phytostimulation

PubMed Central

Pelagio-Flores, Ramón; Esparza-Reynoso, Saraí; Garnica-Vergara, Amira; López-Bucio, José; Herrera-Estrella, Alfredo

2017-01-01

Trichoderma spp. are common rhizosphere inhabitants widely used as biological control agents and their role as plant growth promoting fungi has been established. Although soil pH influences several fungal and plant functional traits such as growth and nutrition, little is known about its influence in rhizospheric or mutualistic interactions. The role of pH in the Trichoderma–Arabidopsis interaction was studied by determining primary root growth and lateral root formation, root meristem status and cell viability, quiescent center (QC) integrity, and auxin inducible gene expression. Primary root growth phenotypes in wild type seedlings and STOP1 mutants allowed identification of a putative root pH sensing pathway likely operating in plant–fungus recognition. Acidification by Trichoderma induced auxin redistribution within Arabidopsis columella root cap cells, causing root tip bending and growth inhibition. Root growth stoppage correlated with decreased cell division and with the loss of QC integrity and cell viability, which were reversed by buffering the medium. In addition, stop1, an Arabidopsis mutant sensitive to low pH, was oversensitive to T. atroviride primary root growth repression, providing genetic evidence that a pH root sensing mechanism reprograms root architecture during the interaction. Our results indicate that root sensing of pH mediates the interaction of Trichoderma with plants. PMID:28567051

Influence of rate of force application during compression on tablet capping.

PubMed

Sarkar, Srimanta; Ooi, Shing Ming; Liew, Celine Valeria; Heng, Paul Wan Sia

2015-04-01

Root cause and possible processing remediation of tablet capping were investigated using a specially designed tablet press with an air compensator installed above the precompression roll to limit compression force and allow extended dwell time in the precompression event. Using acetaminophen-starch (77.9:22.1) as a model formulation, tablets were prepared by various combinations of precompression and main compression forces, set precompression thickness, and turret speed. The rate of force application (RFA) was the main factor contributing to the tablet mechanical strength and capping. When target force above the force required for strong interparticulate bond formation, the resultant high RFA contributed to more pronounced air entrapment, uneven force distribution, and consequently, stratified densification in compact together with high viscoelastic recovery. These factors collectively had contributed to the tablet capping. As extended dwell time assisted particle rearrangement and air escape, a denser and more homogenous packing in the die could be achieved. This occurred during the extended dwell time when a low precompression force was applied, followed by application of main compression force for strong interparticulate bond formation that was the most beneficial option to solve capping problem. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

Simulated microgravity impacts the plant plasmalemma lipid bilayer

NASA Astrophysics Data System (ADS)

Nedukha, Olena; Berkovich, Yuliy A.; Vorobyeva, Tamara; Grakhov, Volodimir; Klimenko, Elena; Zhupanov, Ivan; Jadko, Sergiy

Biological membranes, especially the plasmalemma, and their properties and functions can be considered one of the most sensitive indicators of gravity interaction or alteration of gravity, respectively. Studies on the molecular basis of cellular signal perception and transduction are very important in order to understand signal responses at the cellular and organism level. The plasmalemma lipid bilayer is the boundary between the cell internal and external environment and mediates communication between them. Therefore, we studied the content and composition of lipids, saturated and unsaturated fatty acids, sterols, and microviscosity in the plasmalemma isolated from pea seedling roots and epicotyls grown in the stationary conditions and under slow horizontal clinorotation. In addition, lipid peroxidation intensity of intact roots was also identified. The plasmalemma fraction was isolated by the two-phase aquatic-polymer system optimized for pea using a centrifuge Optima L-90K. Lipid bilayer components were determined by using highly effective liquid chromatography with a system Angilent 1100 (Germany). Spontaneous chemiluminescence intensity was measured with a chemiluminometer ChLMTS-01. The obtained data showed that plasmalemma investigated parameters are sensitive to clinorotation, namely: increasing or decreasing the different lipids content, among which, phospho- and glycolipids were dominated, as well as changes in the content of saturated and unsaturated fatty acids and sterols. A degree of plasmalemma sensitivity to clinorotation was higher for the root plasmalemma than epicocotyl ones. This distinguish may be naturally explained by the differences in the structure, cell types, growth, and specific functions of a root and an epicotyl, those are the most complicated in roots. An index of unsaturation under clinorotation was similar to that in the stationary conditions as a result of the certain balance between changes in the content of saturated and unsaturated fatty acids, that maintains the plasmalemma fluidity in the normal limits, and it may be considered as an adaptive pattern. This assumption was directly confirmed by the data on plasmalemma fluidity in control and under clinorotation defined by electron paramagnetic resonance spectrometer Bruker Elexsys E 580 (Germany). It was in the first established a significant increase in the sterol content under clinorotation. It is of much interest because sterols along with glyco- and phospholipids and mainly saturated fatty acids form “rafts” that are membrane certain domains, where a lipid bilayer is in the dense, highly ordered state. As rafts include the protein complexes, which are necessary for perception and transduction of exogenous signals, stress protection, pathogenesis, vesicular transport also, a significant increase of sterols under clinorotation may indicate the changes in both membrane permeability and protein activity. On the basis of obtained data, the future researches of components of signaling pathways and regulation of certain plasmalemma membranous proteins activity are grounded and planned.

Springback in root gravitropism

NASA Technical Reports Server (NTRS)

Leopold, A. C.; Wettlaufer, S. H.

1989-01-01

Conditions under which a gravistimulus of Merit corn roots (Zea mays L.) is withdrawn result in a subsequent loss of gravitropic curvature, an effect which we refer to as springback.' This loss of curvature begins within 1 to 10 minutes after removal of the gravistimulus. It occurs regardless of the presence or absence of the root cap. It is insensitive to inhibitors of auxin transport (2,3,5-triiodobenzoic acid, naphthylphthalamic [correction of naphthylphthalmaic] acid) or to added auxin (2,4-dichlorophenoxyacetic acid). Springback is prevented if a clinostat treatment is interjected to neutralize gravistimulation during germination, which suggests that the change in curvature is a response to a memory' effect carried over from a prior gravistimulation.

Springback in Root Gravitropism 1

PubMed Central

Leopold, A. Carl; Wettlaufer, Scott H.

1989-01-01

Conditions under which a gravistimulus of Merit corn roots (Zea mays L.) is withdrawn result in a subsequent loss of gravitropic curvature, an effect which we refer to as `springback.' This loss of curvature begins within 1 to 10 minutes after removal of the gravistimulus. It occurs regardless of the presence or absence of the root cap. It is insensitive to inhibitors of auxin transport (2,3,5-triiodobenzoic acid, naphthylphthalmaic acid) or to added auxin (2,4-dichlorophenoxyacetic acid). Springback is prevented if a clinostat treatment is interjected to neutralize gravistimulation during germination, which suggests that the change in curvature is a response to a `memory' effect carried over from a prior gravistimulation. PMID:11537456

Enzymatically and reductively degradable α-amino acid-based poly(ester amide)s: synthesis, cell compatibility, and intracellular anticancer drug delivery.

PubMed

Sun, Huanli; Cheng, Ru; Deng, Chao; Meng, Fenghua; Dias, Aylvin A; Hendriks, Marc; Feijen, Jan; Zhong, Zhiyuan

2015-02-09

A novel and versatile family of enzymatically and reductively degradable α-amino acid-based poly(ester amide)s (SS-PEAs) were developed from solution polycondensation of disulfide-containing di-p-toluenesulfonic acid salts of bis-l-phenylalanine diesters (SS-Phe-2TsOH) with di-p-nitrophenyl adipate (NA) in N,N-dimethylformamide (DMF). SS-PEAs with Mn ranging from 16.6 to 23.6 kg/mol were obtained, depending on NA/SS-Phe-2TsOH molar ratios. The chemical structures of SS-PEAs were confirmed by (1)H NMR and FTIR spectra. Thermal analyses showed that the obtained SS-PEAs were amorphous with a glass transition temperature (Tg) in the range of 35.2-39.5 °C. The in vitro degradation studies of SS-PEA films revealed that SS-PEAs underwent surface erosion in the presence of 0.1 mg/mL α-chymotrypsin and bulk degradation under a reductive environment containing 10 mM dithiothreitol (DTT). The preliminary cell culture studies displayed that SS-PEA films could well support adhesion and proliferation of L929 fibroblast cells, indicating that SS-PEAs have excellent cell compatibility. The nanoparticles prepared from SS-PEA with PVA as a surfactant had an average size of 167 nm in phosphate buffer (PB, 10 mM, pH 7.4). SS-PEA nanoparticles while stable under physiological environment undergo rapid disintegration under an enzymatic or reductive condition. The in vitro drug release studies showed that DOX release was accelerated in the presence of 0.1 mg/mL α-chymotrypsin or 10 mM DTT. Confocal microscopy observation displayed that SS-PEA nanoparticles effectively transported DOX into both drug-sensitive and -resistant MCF-7 cells. MTT assays revealed that DOX-loaded SS-PEA nanoparticles had a high antitumor activity approaching that of free DOX in drug-sensitive MCF-7 cells, while more than 10 times higher than free DOX in drug-resistant MCF-7/ADR cells. These enzymatically and reductively degradable α-amino acid-based poly(ester amide)s have provided an appealing platform for biomedical technology in particular controlled drug delivery applications.

Rhythms and outcomes of adult in-hospital cardiac arrest.

PubMed

Meaney, Peter A; Nadkarni, Vinay M; Kern, Karl B; Indik, Julia H; Halperin, Henry R; Berg, Robert A

2010-01-01

To determine the relationship of electrocardiographic rhythm during cardiac arrest with survival outcomes. Prospective, observational study. Total of 411 hospitals in the National Registry of Cardiopulmonary Resuscitation. Total of 51,919 adult patients with pulseless cardiac arrests from April 1999 to July 2005. Registry data collected included first documented rhythm, patient demographics, pre-event data, event data, and survival and neurologic outcome data. Of 51,919 indexed cardiac arrests, first documented pulseless rhythm was ventricular tachycardia (VT) in 3810 (7%), ventricular fibrillation (VF) in 8718 (17%), pulseless electrical activity (PEA) in 19,262 (37%) and asystole 20,129 (39%). Subsequent VT/VF (that is, VT or VF occurring during resuscitation for PEA or asystole) occurred in 5154 (27%), with first documented rhythm of PEA and 4988 (25%) with asystole. Survival to hospital discharge rate was not different between those with first documented VF and VT (37% each, adjusted odds ratio [OR]) 1.08; 95% confidence interval [CI] 0.95-1.23). Survival to hospital discharge was slightly more likely after PEA than asystole (12% vs. 11%, adjusted OR 1.1; 95% CI 1.00-1.18), Survival to discharge was substantially more likely after first documented VT/VF than PEA/asystole (adjusted OR 1.68; 95% CI 1.55-1.82). Survival to discharge was also more likely after PEA/asystole without subsequent VT/VF compared with PEA/asystole with subsequent VT/VF (14% vs. 7% for PEA without vs. with subsequent VT/VF; 12% vs. 8% for asystole without vs. with subsequent VT/VF; adjusted OR 1.60; 95% CI, 1.44-1.80). Survival to hospital discharge was substantially more likely when the first documented rhythm was shockable rather than nonshockable, and slightly more likely after PEA than asystole. Survival to hospital discharge was less likely following PEA/asystole with subsequent VT/VF compared to PEA/asystole without subsequent VT/VF.

Involvement of Activated Oxygen in Nitrate-Induced Senescence of Pea Root Nodules.

PubMed Central

Escuredo, P. R.; Minchin, F. R.; Gogorcena, Y.; Iturbe-Ormaetxe, I.; Klucas, R. V.; Becana, M.

1996-01-01

The effect of short-term nitrate application (10 mM, 0-4 d) on nitrogenase (N2ase) activity, antioxidant defenses, and related parameters was investigated in pea (Pisum sativum L. cv Frilene) nodules. The response of nodules to nitrate comprised two stages. In the first stage (0-2 d), there were major decreases in N2ase activity and N2ase-linked respiration and concomitant increases in carbon cost of N2ase and oxygen diffusion resistance of nodules. There was no apparent oxidative damage, and the decline in N2ase activity was, to a certain extent, reversible. The second stage (>2 d) was typical of a senescent, essentially irreversible process. It was characterized by moderate increases in oxidized proteins and catalytic Fe and by major decreases in antioxidant enzymes and metabolites. The restriction in oxygen supply to bacteroids may explain the initial decline in N2ase activity. The decrease in antioxidant protection is not involved in this process and is not specifically caused by nitrate, since it also occurs with drought stress. However, comparison of nitrate- and drought-induced senescence shows an important difference: there is no lipid degradation or lipid peroxide accumulation with nitrate, indicating that lipid peroxidation is not necessarily involved in nodule senescence. PMID:12226252

Manipulating Membrane Fatty Acid Compositions of Whole Plants with Tween-Fatty Acid Esters 1

PubMed Central

Terzaghi, William B.

1989-01-01

This paper describes a method for manipulating plant membrane fatty acid compositions without altering growth temperature or other conditions. Tween-fatty acid esters carrying specific fatty acids were synthesized and applied to various organs of plants growing axenically in glass jars. Treated plants incorporated large amounts of exogenous fatty acids into all acylated membrane lipids detected. Fatty acids were taken up by both roots and leaves. Fatty acids applied to roots were found in leaves, while fatty acids applied to leaves appeared in both leaves higher on the plant and in roots, indicating translocation (probably in the phloem). Foliar application was most effective; up to 20% of membrane fatty acids of leaves above the treated leaf and up to 40% of root membrane fatty acids were exogenously derived. Plants which took up exogenous fatty acids changed their patterns of fatty acid synthesis such that ratios of saturated to unsaturated fatty acids remained essentially unaltered. Fatty acid uptake was most extensively studied in soybean (Glycine max [L.] Merr.), but was also observed in other species, including maize (Zea mays L.), mung beans (Vigna radiata L.), peas (Pisum sativum L.), petunia (Petunia hybrida L.) and tomato (Lycopersicon esculentum Mill.). Potential applications of this system include studying internal transport of fatty acids, regulation of fatty acid and membrane synthesis, and influences of membrane fatty acid composition on plant physiology. Images Figure 2 PMID:16666997

Enhanced Macrophage Resistance to Pseudomonas Exotoxin A Is Correlated with Decreased Expression of the Low-Density Lipoprotein Receptor-Related Protein

PubMed Central

Laithwaite, James E.; Benn, Sally J.; Yamate, Jyoji; FitzGerald, David J.; LaMarre, Jonathan

1999-01-01

Cellular intoxification by exotoxin A of Pseudomonas aeruginosa (PEA) begins when PEA binds to its cellular receptor, the low-density lipoprotein receptor-related protein (LRP). This receptor is particularly abundant on macrophages. We hypothesize here that inducible changes in cellular expression levels of the LRP represent an important mechanism by which macrophage susceptibility to PEA is regulated by the host. We have examined the effect of lipopolysaccharide (LPS) on LRP expression and PEA sensitivity in the macrophage-like cell line HS-P. Using a [3H]leucine incorporation assay to measure inhibition of protein synthesis, we have demonstrated that HS-P macrophages are highly sensitive to PEA and that PEA toxicity is decreased by the LRP antagonist receptor-associated protein. LPS pretreatment decreases HS-P PEA sensitivity in a time- and dose-dependent manner. The dose of toxin required to inhibit protein synthesis by 50% increased from 11.3 ± 1.2 ng/ml in untreated cells to 25.7 ± 2.0 ng/ml in cells treated with LPS. In pulse experiments, involving brief exposure to saturating concentrations of PEA, [3H]leucine incorporation was more than threefold higher in cells pretreated with LPS than in untreated macrophages. These changes in HS-P PEA sensitivity following LPS treatment were consistently associated with a fivefold decrease in HS-P LRP mRNA expression as measured by Northern blot analysis and a three-and-a-half-fold decrease in HS-P LRP-specific ligand internalization as determined by activated α2-macroglobulin internalization studies. These data demonstrate for the first time that modulation of LRP levels by extracellular signaling molecules can alter cellular PEA sensitivity. PMID:10531236

Nitroxyl radical incorporated electrospun biodegradable poly(ester Amide) nanofiber membranes.

PubMed

Li, Lei; Chu, Chih-Chang

2009-01-01

Biodegradable amino-acid-based poly(ester amide) (PEA) ultra-fine fibers pre-loaded with a nitroxyl radical model compound, 4-amino-2.2.6.6-tetramethylpiperidine-1-oxy (4-amino-TEMPO), were prepared by electrospinning. The fiber size and morphology were shown to be greatly affected by the composition ratio of the solvent mixture (chloroform to DMF) prepared for electrospinning. Nano-size PEA fibers (approx. 640 nm) were obtained when PEA dope was electrospun from the chloroform/DMF solvent mixture at a volume ratio of 2 to 1 vs. 3.5 mum size PEA fibers obtained from chloroform-based electrospun dope. Due to the low glass transition temperature and completely amorphous structures, the PEA electrospun fibrous membranes gradually lost their fiber characteristic during 1 month incubation in PBS buffer at 37 degrees C. The glass transition temperature and heat of fusion of PEA electrospun fibers increased with an increasing incubation time and the most significant change occurred in the first day of incubation in PBS. A sustained release of 4-amino-TEMPO from the electrospun PEA nanofiber membranes was observed over the 1-month incubation period in PBS buffer at 37 degrees C and 38% of the incorporated 4-amino-TEMPO (initial loading level 10 mg/g PEA fibers) was released in one month. During this 1 month incubation in PBS buffer, there were only 1.2% weight loss and 11.7% molecular weight reduction for the electrospun PEA fibrous membranes. In an alpha-chymotrypsin medium (0.1 mg/ml PBS), however, the same electrospun PEA fibrous membranes showed more than 80% weight loss within 6 days and a complete release of encapsulated 4-amino-TEMPO within 5 days.

Management and outcomes in chronic thromboembolic pulmonary hypertension: From expert centers to a nationwide perspective.

PubMed

Escribano-Subías, P; Del Pozo, R; Román-Broto, A; Domingo Morera, J A; Lara-Padrón, A; Elías Hernández, T; Molina-Ferragut, L; Blanco, I; Cortina, J; Barberà, J A

2016-01-15

The Spanish "Registry of Pulmonary Arterial Hypertension" (REHAP), started in 2007, includes chronic thromboembolic hypertension (CTEPH) patients. Based on data provided by this registry and retrospective data from patients diagnosed during 2006 (≤ 12 months since the registry was created), clinical management and long-term outcomes of CTEPH patients are analyzed nationwide for the first time in a scenario of a decentralized organization model of CTEPH management. A total of 391 patients (median [Q1:Q3] age 63.7 [48.0;73.3] years, 58% females) with CTEPH included during the period January 1, 2006-December 31, 2013 in the REHAP registry were analyzed. Rate of pulmonary endarterectomy (PEA) was 31.2%, and highly asymmetric among centers: rate was 47.9% at two centers designated as CTEPH expert centers, while it was 4.6% in other centers. Among patients not undergoing PEA, 82% were treated with therapies licensed for pulmonary arterial hypertension (PAH). Five-year survival rate was 86.3% for PEA patients, and 64.9% for non-PEA patients. Among non-PEA patients, presenting proximal lesions (42% of non-referred patients) was associated with a 3-fold increase in mortality. PEA patients achieved significantly better hemodynamic and clinical outcomes at one-year follow-up compared to non-PEA patients. Patients not being referred for PEA assessment were older and had a worse functional capacity. Older age was the most deterrent factor for non-operability. Despite the increase in diagnosis and expertise in PEA-specialized centers, an important percentage of patients do not benefit of PEA in a decentralized organization model of CTEPH management. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Growth performance and carcass characteristics of guinea fowl broilers fed micronized-dehulled pea (Pisum sativum L.) as a substitute for soybean meal.

PubMed

Laudadio, V; Nahashon, S N; Tufarelli, V

2012-11-01

This study was conducted to evaluate the effect of substitution of soybean meal (SBM) with dehulled-micronized peas (Pisum sativum) in diets of guinea fowl broilers on their growth performance, carcass yields, and fatty acid composition of meat. One hundred forty 1-d-old guinea fowl keets were randomly assigned to 2 dietary treatments, which were fed from hatch to 12 wk. The birds were fed 2 wheat middling-based diets comprising a control diet, which contained SBM (78 g/kg) and a test diet containing dehulled-micronized peas (180 g/kg) as the main protein source. The substitution of SBM with peas had no adverse effect on growth performance, dressing percentage, or breast and thigh muscle relative weights of the guinea broilers. However, a reduction of abdominal fat content (P < 0.05) was observed in birds fed the pea diet compared with the control. Breast and thigh meat of birds fed the pea diet had higher lightness scores (P < 0.05) and water-holding capacity (P < 0.01) than the control. Meat from guinea fowls fed the pea diet had less cholesterol (P < 0.01) and lipids (P < 0.05), and higher concentrations of phospholipids (P < 0.05). Feeding peas increased polyunsaturated fatty acid concentration in breast and thigh muscles, and decreased the saturated fatty acid concentration. Feeding the pea diet also lowered the n-6/n-3 polyunsaturated fatty acid ratio of the guinea broiler muscles. Our results suggest that replacing the conventional SBM as the protein source with dehulled-micronized pea meal in diets of guinea fowls broilers can improve carcass quality and favorable lipid profile without adversely affecting growth performance traits.

Growth Chambers on the International Space Station for Large Plants

NASA Technical Reports Server (NTRS)

Massa, G. D.; Wheeler, R. M.; Morrow, R. C.; Levine, H. G.

2016-01-01

The International Space Station (ISS) now has platforms for conducting research on horticultural plant species under LED lighting, and those capabilities continue to expand. The 'Veggie' vegetable production system was deployed to the ISS as an applied research platform for food production in space. Veggie is capable of growing a wide array of horticultural crops. It was designed for low power usage, low launch mass and stowage volume, and minimal crew time requirements. The Veggie flight hardware consists of a light cap containing red (630 nm), blue, (455 nm) and green (530 nm) LEDs. Interfacing with the light cap is an extendable bellows/baseplate for enclosing the plant canopy. A second large plant growth chamber, the Advanced Plant Habitat (APH), is will fly to the ISS in 2017. APH will be a fully controllable environment for high-quality plant physiological research. APH will control light (quality, level, and timing), temperature, CO2, relative humidity, and irrigation, while scrubbing any cabin or plant-derived ethylene and other volatile organic compounds. Additional capabilities include sensing of leaf temperature and root zone moisture, root zone temperature, and oxygen concentration. The light cap will have red (630 nm), blue (450 nm), green (525 nm), far red (730 nm) and broad spectrum white LEDs (4100K). There will be several internal cameras (visible and IR) to monitor and record plant growth and operations. Veggie and APH are available for research proposals.

Direct Pulp Capping with Calcium Hydroxide, Mineral Trioxide Aggregate, and Biodentine in Permanent Young Teeth with Caries: A Randomized Clinical Trial.

PubMed

Brizuela, Claudia; Ormeño, Andrea; Cabrera, Carolina; Cabezas, Roxana; Silva, Carolina Inostroza; Ramírez, Valeria; Mercade, Montse

2017-11-01

Direct pulp capping treatment is intended to preserve pulp vitality, to avoid or retard root canal treatment, and, in cases with an open apex, to allow continued root development. Historically, calcium hydroxide (CH) was the gold standard material, but nowadays calcium silicate materials (CSMs) are displacing CH because of their high bioactivity, biocompatibility, sealing ability, and mechanical properties. However, more randomized clinical trials are needed to confirm the appropriateness of CSMs as replacement materials for CH in direct pulp capping procedures. A randomized clinical trial was conducted that included 169 patients (mean age, 11.3 years) from the Maipo district (Chile). The inclusion criterion was patients with 1 carious permanent tooth with pulpal exposure, a candidate for a direct pulp capping procedure. The patients were randomly allocated to one of the experimental groups (CH, Biodentine, or mineral trioxide aggregate [MTA]). Clinical follow-up examinations were performed at 1 week, 3 months, 6 months, and 1 year. The Fisher exact test was performed. At the follow-up examination at 1 week, the patients showed 100% clinical success. At 3 months, there was 1 failure in the CH group. At 6 months, there were 4 new failures (1 in the CH group and 3 in the MTA group). At 1 year, there was another failure in the CH group. There were no statistically significant differences among the experimental groups. CSMs appear to be suitable materials to replace CH. Although no significant differences were found among the materials studied, Biodentine and MTA offered some advantages over CH. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Ammonium-induced loss of root gravitropism is related to auxin distribution and TRH1 function, and is uncoupled from the inhibition of root elongation in Arabidopsis.

PubMed

Zou, Na; Li, Baohai; Dong, Gangqiang; Kronzucker, Herbert J; Shi, Weiming

2012-06-01

Root gravitropism is affected by many environmental stresses, including salinity, drought, and nutrient deficiency. One significant environmental stress, excess ammonium (NH(4)(+)), is well documented to inhibit root elongation and lateral root formation, yet little is known about its effects on the direction of root growth. We show here that inhibition of root elongation upon elevation of external NH(4)(+) is accompanied by a loss in root gravitropism (agravitropism) in Arabidopsis. Addition of potassium (K(+)) to the treatment medium partially rescued the inhibition of root elongation by high NH(4)(+) but did not improve gravitropic root curvature. Expression analysis of the auxin-responsive reporter gene DR5::GUS revealed that NH(4)(+) treatment delayed the development of gravity-induced auxin gradients across the root cap but extended their duration once initiated. Moreover, the β-glucuronidase (GUS) signal intensity in root tip cells was significantly reduced under high NH(4)(+) treatment over time. The potassium carrier mutant trh1 displayed different patterns of root gravitropism and DR5::GUS signal intensity in root apex cells compared with the wild type in response to NH(4)(+). Together, the results demonstrate that the effects of NH(4)(+) on root gravitropism are related to delayed lateral auxin redistribution and the TRH1 pathway, and are largely independent of inhibitory effects on root elongation.

Carbohydrates

MedlinePlus

... such as kidney beans, black beans, pinto beans, black-eyed peas, split peas, and garbanzo beans Starchy vegetables, such as potatoes, corn, green peas, and parsnips Whole grains, such as brown rice, oats, barley, and quinoa Refined grains, such as ...

The inhibitory effects of capillarisin on cell proliferation and invasion of prostate carcinoma cells.

PubMed

Tsui, Ke-Hung; Chang, Ying-Ling; Yang, Pei-Shan; Hou, Chen-Pang; Lin, Yu-Hsiang; Lin, Bing-Wei; Feng, Tsui-Hsia; Juang, Horng-Heng

2018-04-01

Capillarisin (Cap), an active component of Artemisia capillaris root extracts, is characterized by its anti-inflammatory, anti-oxidant and anti-cancer properties. Nevertheless, the functions of Cap in prostate cancer have not been fully explored. We evaluated the potential actions of Cap on the cell proliferation, migration and invasion of prostate carcinoma cells. Cell proliferation and cell cycle distribution were measured by water-soluble tetrazolium-1 and flow cytometry assays. The expression of cyclins, p21, p27, survivin, matrix metallopeptidase (MMP2 and MMP9) were assessed by immunoblotting assays. Effects of Cap on invasion and migration were determined by wound closure and matrigel transmigration assays. The constitutive and interlukin-6 (IL-6)-inducible STAT3 activation of prostate carcinoma cells were determined by immunoblotting and reporter assays. Capillarisin inhibited androgen-independent DU145 and androgen-dependent LNCaP cell growth through the induction of cell cycle arrest at the G0/G1 phase by upregulating p21 and p27 while downregulating expression of cyclin D1, cyclin A and cyclin B. Cap decreased protein expression of survivin, MMP-2, and MMP-9 and therefore blocked the migration and invasion of DU145 cells. Cap suppressed constitutive and IL-6-inducible STAT3 activation in DU145 and LNCaP cells. Our data indicate that Cap blocked cell growth by modulation of p21, p27 and cyclins. The inhibitory effects of Cap on survivin, MMP-2, MMP-9 and STAT3 activation may account for the suppression of invasion in prostate carcinoma cells. Our data suggest that Cap might be a therapeutic agent in treating advanced prostate cancer with constitutive STAT3 or IL-6-inducible STAT3 activation. © 2017 John Wiley & Sons Ltd.

Characterization of LeMir, a Root-Knot Nematode-Induced Gene in Tomato with an Encoded Product Secreted from the Root1

PubMed Central

Brenner, Eric D.; Lambert, Kris N.; Kaloshian, Isgouhi; Williamson, Valerie M.

1998-01-01

A tomato gene that is induced early after infection of tomato (Lycopersicon esculentum Mill.) with root-knot nematodes (Meloidogyne javanica) encodes a protein with 54% amino acid identity to miraculin, a flavorless protein that causes sour substances to be perceived as sweet. This gene was therefore named LeMir (L. esculentum miraculin). Sequence similarity places the encoded protein in the soybean trypsin-inhibitor family (Kunitz). LeMir mRNA is found in root, hypocotyl, and flower tissues, with the highest expression in the root. Rapid induction of expression upon nematode infection is localized to root tips. In situ hybridization shows that LeMir is expressed constitutively in the root-cap and root-tip epidermis. The LeMir protein product (LeMir) was produced in the yeast Pichia pastoris for generation of antibodies. Western-blot analysis showed that LeMir expression is up-regulated by nematode infection and by wounding. LeMir is also expressed in tomato callus tissue. Immunoprint analysis revealed that LeMir is expressed throughout the seedling root, but that levels are highest at the root/shoot junction. Analysis of seedling root exudates revealed that LeMir is secreted from the root into the surrounding environment, suggesting that it may interact with soil-borne microorganisms. PMID:9733543

Effect of genotype and environment on the concentrations of starch and protein in, and the physicochemical properties of starch from, field pea and fababean.

PubMed

Hood-Niefer, Shannon D; Warkentin, Thomas D; Chibbar, Ravindra N; Vandenberg, Albert; Tyler, Robert T

2012-01-15

The effects of genotype and environment and their interaction on the concentrations of starch and protein in, and the amylose content and thermal and pasting properties of starch from, pea and fababean are not well known. Differences due to genotype were observed in the concentrations of starch and protein in pea and fababean, in the onset temperature (To) and peak temperature (Tp) of gelatinization of fababean starch, and in the pasting, trough, cooling and final viscosities of pea starch and fababean starch. Significant two-way interactions (location × genotype) were observed for the concentration of starch in fababean and the amylose content, To, endothermic enthalpy of gelatinization (ΔH) and trough viscosity of fababean starch. Significant three-way interactions (location × year × genotype) were observed for the concentration of starch in pea and the pasting, trough, cooling and final viscosities of pea starch. Differences observed in the concentrations of starch and protein in pea and fababean were sufficient to be of practical significance to end-users, but the relatively small differences in amylose content and physicochemical properties of starch from pea and fababean were not. Copyright © 2011 Society of Chemical Industry.

Genetic Manipulation of Palmitoylethanolamide Production and Inactivation in Saccharomyces cerevisiae

PubMed Central

Muccioli, Giulio G.; Sia, Angela; Muchowski, Paul J.; Stella, Nephi

2009-01-01

Background Lipids can act as signaling molecules, activating intracellular and membrane-associated receptors to regulate physiological functions. To understand how a newly discovered signaling lipid functions, it is necessary to identify and characterize the enzymes involved in their production and inactivation. The signaling lipid N-palmitoylethanolamine (PEA) is known to activate intracellular and membrane-associated receptors and regulate physiological functions, but little is known about the enzymes involved in its production and inactivation. Principal Findings Here we show that Saccharomyces cerevisiae produce and inactivate PEA, suggesting that genetic manipulations of this lower eukaryote may be used to identify the enzymes involved in PEA metabolism. Accordingly, using single gene deletion mutants, we identified yeast genes that control PEA metabolism, including SPO14 (a yeast homologue of the mammalian phospholipase D) that controls PEA production and YJU3 (a yeast homologue of the mammalian monoacylglycerol lipase) that controls PEA inactivation. We also found that PEA metabolism is affected by heterologous expression of two mammalian proteins involved in neurodegenerative diseases, namely huntingtin and α-synuclein. Significance Together these findings show that forward and reverse genetics in S. cerevisiae can be used to identify proteins involved in PEA production and inactivation, and suggest that mutated proteins causing neurodegenerative diseases might affect the metabolism of this important signaling lipid. PMID:19529773

Strains of Pseudomonas syringae pv. syringae from pea are phylogenetically and pathogenically diverse.

PubMed

Martín-Sanz, Alberto; de la Vega, Marcelino Pérez; Murillo, Jesús; Caminero, Constantino

2013-07-01

Pseudomonas syringae pv. syringae causes extensive yield losses in the pea crop worldwide, although there is little information on its host specialization and its interactions with pea. A collection of 88 putative P. syringae pv. syringae strains (including 39 strains isolated from pea) was characterized by repetitive polymerase chain reaction (rep-PCR), multilocus sequence typing (MLST), and syrB amplification and evaluated for pathogenicity and virulence. rep-PCR data grouped the strains from pea into two groups (1B and 1C) together with strains from other hosts; a third group (1A) was formed exclusively with strains isolated from non-legume species. MLST data included all strains from pea in the genomospecies 1 of P. syringae pathovars defined in previous studies; they were distributed in the same three groups defined by rep-PCR. The inoculations performed in two pea cultivars showed that P. syringae pv. syringae strains from groups 1A and 1C were less virulent than strains from group 1B, suggesting a possible pathogenic specialization in this group. This study shows the existence of genetically and pathogenically distinct P. syringae pv. syringae strain groups from pea, which will be useful for the diagnostic and epidemiology of this pathogen and for disease resistance breeding.

Influence of grinding on the nutritive value of peas for ruminants: comparison between in vitro and in situ approaches

PubMed Central

Giger-Reverdin, Sylvie; Maaroufi, Chiraze; Chapoutot, Patrick; Peyronnet, Corinne; Sauvant, Daniel

2014-01-01

In ruminant nutrition, peas are characterized by high protein solubility and degradability, which impair its protein value estimated by the official in situ method. Grinding can be used as a technological treatment of pea seeds to modify their nutritional value. The aim of this study was to compare the in situ method with an in vitro method on the same pea either in a coarse pea flour form (PCF) or in a ground pea fine flour form (PFF) to understand the effect of grinding. Both forms were also reground (GPCF and GPFF). PCF presented a lower rate of in vitro degradation than PFF, and more stable fermentation parameters (pH, ammonia, soluble carbohydrates) even if gas production was higher for the PCF after 48 h of incubation. In situ dry matter and protein degradation were lower for PCF than those for PFF; these differences were more marked than with the in vitro method. Reground peas were very similar to PFF. The values for pea protein digestible in the intestine (PDI) were higher for PCF than those for PFF. This study points out the high sensitivity of the in situ method to grinding. The study needs to be validated by in vivo measurements. PMID:25473488

Beneficial Effects of Co-Ultramicronized Palmitoylethanolamide/Luteolin in a Mouse Model of Autism and in a Case Report of Autism.

PubMed

Bertolino, Bartolomeo; Crupi, Rosalia; Impellizzeri, Daniela; Bruschetta, Giuseppe; Cordaro, Marika; Siracusa, Rosalba; Esposito, Emanuela; Cuzzocrea, Salvatore

2017-01-01

Autism spectrum disorder (ASD) is a condition defined by social communication deficits and repetitive restrictive behaviors. Association of the fatty acid amide palmitoylethanolamide (PEA) with the flavonoid luteolin displays neuroprotective and antiinflammatory actions in different models of central nervous system pathologies. We hypothesized that association of PEA with luteolin might have therapeutic utility in ASD, and we employed a well-recognized autism animal model, namely sodium valproate administration, to evaluate cognitive and motor deficits. Two sets of experiments were conducted. In the first, we investigated the effect of association of ultramicronized PEA with luteolin, co-ultramicronized PEA-LUT® (co-ultraPEA-LUT®) in a murine model of autistic behaviors, while in the second, the effect of co-ultraPEA-LUT® in a patient affected by ASD was examined. Co-ultraPEA-LUT® treatment ameliorated social and nonsocial behaviors in valproic acid-induced autistic mice and improved clinical picture with reduction in stereotypes in a 10-year-old male child. These data suggest that ASD symptomatology may be improved by agents documented to control activation of mast cells and microglia. Co-ultraPEA-LUT® might be a valid and safe therapy for the symptoms of ASD alone or in combination with other used drugs. © 2016 John Wiley & Sons Ltd.

Palmitoylethanolamide Supplementation during Sensitization Prevents Airway Allergic Symptoms in the Mouse

PubMed Central

Roviezzo, Fiorentina; Rossi, Antonietta; Caiazzo, Elisabetta; Orlando, Pierangelo; Riemma, Maria A.; Iacono, Valentina M.; Guarino, Andrea; Ialenti, Armando; Cicala, Carla; Peritore, Alessio; Capasso, Raffaele; Di Marzo, Vincenzo; Izzo, Angelo A.

2017-01-01

One important risk factor for the development of asthma is allergen sensitization. Recent increasing evidence suggests a prominent role of mast cells in asthma pathophysiology. Since Palmitoylethanolamide (PEA), an endogenous lipid mediator chemically related to – and co-released with- the endocannabinoid anandamide, behaves as a local autacoid down-regulator of mast cell activation and inflammation, we explored the possible contribution of PEA in allergic sensitization, by using ovalbumin (OVA) as sensitizing agent in the mouse. PEA levels were dramatically reduced in the bronchi of OVA-treated animals. This effect was coupled to a significant up-regulation of CB2 and GPR55 receptors, two of the proposed molecular PEA targets, in bronchi harvested from allergen-sensitized mice. PEA supplementation (10 mg/kg, 15 min before each allergen exposure) prevented OVA-induced bronchial hyperreactivity, but it did not affect IgE plasma increase. On the other hand, PEA abrogated allergen-induced cell recruitment as well as pulmonary inflammation. Evaluation of pulmonary sections evidenced a significant inhibitory action of PEA on pulmonary mast cell recruitment and degranulation, an effect coupled to a reduction of leukotriene C4 production. These findings demonstrate that allergen sensitization negatively affects PEA bronchial levels and suggest that its supplementation has the potential to prevent the development of asthma-like features. PMID:29311913

Palmitoylethanolamide stimulates phagocytosis of Escherichia coli K1 by macrophages and increases the resistance of mice against infections.

PubMed

Redlich, Sandra; Ribes, Sandra; Schütze, Sandra; Nau, Roland

2014-06-14

Palmitoylethanolamide (PEA), an endogenous lipid and a congener of anandamide, possesses a wide range of effects related to metabolic and cellular homeostasis including anti-inflammatory and neuroprotective properties. In vitro, we studied the ability of macrophages to phagocytose Escherichia coli K1 after stimulation with increasing doses of PEA. In vivo, wild-type mice were treated with PEA intraperitoneally 12 hours and 30 minutes before infection. Meningoencephalitis or sepsis was induced by intracerebral or intraperitoneal infection with E. coli K1. Stimulation of macrophages with PEA for 30 minutes increased the phagocytosis of E. coli K1 without inducing the release of TNFα or CXCL1. Intracellular killing of E. coli K1 was higher in PEA-stimulated than in unstimulated peritoneal macrophages and microglial cells. Pre-treatment with PEA significantly increased survival of mice challenged intracerebrally or intraperitoneally with E. coli K1. This effect was associated with a decreased production of CXCL1, IL-1β and IL-6 in homogenates of spleen and cerebellum in mice treated with PEA. Our observations suggest that these protective effects of PEA in mice can increase the resistance to bacterial infections without the hazard of collateral damage by excessive stimulation of phagocytes.

Large Plant Growth Chambers: Flying Soon on a Space Station near You!

NASA Technical Reports Server (NTRS)

Massa, Gioia D.; Morrow, Robert C.; Levine, Howard G.

2014-01-01

The International Space Station (ISS) now has platforms for conducting research on horticultural plant species, and those capabilities continue to grow. The Veggie vegetable production system will be deployed to the ISS in Spring of 2014 to act as an applied research platform with goals of studying food production in space, providing the crew with a source of fresh food, allowing behavioral health and plant microbiology experimentation, and being a source of recreation and enjoyment for the crew. Veggie was conceived, designed, and constructed by Orbital Technologies Corporation (ORBITEC, Madison, WI). Veggie is the largest plant growth chamber that NASA has flown to date, and is capable of growing a wide array of horticultural crops. It was designed for low energy usage, low launch mass and stowage volume, and minimal crew time requirements. The Veggie flight hardware consists of a light cap containing red (630 nanometers), blue, (455 nanometers) and green (530 nanometers) light emitting diodes. Interfacing with the light cap is an extendable bellows baseplate secured to the light cap via magnetic closures and stabilized with extensible flexible arms. The baseplate contains vents allowing air from the ISS cabin to be pulled through the plant growth area by a fan in the light cap. The baseplate holds a Veggie root mat reservoir that will supply water to plant pillows attached via elastic cords. Plant pillows are packages of growth media and seeds that will be sent to ISS dry and installed and hydrated on orbit. Pillows can be constructed in various sizes for different plant types. Watering will be via passive wicking from the root mat to the pillows. Science procedures will include photography or videography, plant thinning, pollination, harvesting, microbial sampling, water sampling, etcetera. Veggie is one of the ISS flight options currently available for research investigations on plants. The Plant Habitat (PH) is being designed and constructed through a NASA-ORBITEC collaboration, and is scheduled to fly on ISS around 2016. This large plant chamber will control light quality, level, and timing, temperature, CO2, relative humidity, and irrigation, while scrubbing ethylene. Additional monitoring capabilities include leaf temperature sensing and root zone moisture and oxygen sensing. The PH light cap will have red (630 nanometers), blue (450 nanometers), green (525 nanometers), far red (730 nanometers) and broad spectrum white light emitting diodes. There will be several internal cameras to monitor and record plant growth and operations.

Gravistimulus Production in Roots of Corn

NASA Technical Reports Server (NTRS)

Feldman, L. J.

1985-01-01

Because of the similarities in structure of known growth regulators, specifically abscisic acid and xanthoxin, with portions of the violaxanthin molecule, it was suggested that these growth substances normally arise from the breakdown or turnover of carotenoid. The light-induced disappearance of violaxanthin occurs in a time frame coincident with an increase in the levels in cap tissue of substances with growth inhibitor properties. One of the ways by which light may regulate root development, including aspects of gravitropism, is through the production of inhibitory growth substances arising from the turnover of carotenoids.

Managed pollinator CAP coordinated agricultural project: detecting Nosema in time

USDA-ARS?s Scientific Manuscript database

Scientists are looking at the root cause of the Colony Collapse Disorder (CCD) syndrome by searching for new diseases, harmful chemicals or a combination of these factors which could inflict stress on bee colonies pushing them over the edge for recovery. Among multiple suspects identified so far, be...

Intramuscular fatty acid composition of lambs fed diets containing alternative protein sources.

PubMed

Scerra, M; Caparra, P; Foti, F; Cilione, C; Zappia, G; Motta, C; Scerra, V

2011-03-01

Thirty male Merinizzata italiana lambs were divided into three groups after weaning according to live weight. The diet of the three groups differed in the main protein source used in the concentrate, soybean meal for treatment SBM, faba bean for treatment FB and peas for treatment PEA. Lambs were fed ad libitum and slaughtered at about 160 days of age. Meat from the PEA group had higher proportions of the essential fatty acids C18:2 ω-6 and C18:3 ω-3 than from FB and SBM lambs and consequently its derivatives, C20:4 ω-6 and C20:5 ω-3 respectively, were higher in meat from PEA animals, compared to SBM and FB ones. The total n-3 fatty acids were highest in meat from PEA lambs and consequently PEA lambs showed a more favourable n-6/n-3 ratio. In conclusion the use of legume seeds such as peas in lamb diets positively affected intramuscular fatty acid composition. Copyright © 2010 The American Meat Science Association. Published by Elsevier Ltd. All rights reserved.

Morphometric analysis of epidermal differentiation in primary roots of Zea mays

NASA Technical Reports Server (NTRS)

Moore, R.; Smith, H. S.

1990-01-01

Epidermal differentiation in primary roots of Zea mays was divided into six cell types based on cellular shape and cytoplasmic appearance. These six cell types are: 1) apical protoderm, located at the tip of the root pole and characterized by periclinally flattened cells; 2) cuboidal protoderm, located approximately 230 microns from the root pole and characterized by cuboidal cells; 3) tabular epidermis, located approximately 450 microns from the root pole and characterized by anticlinally flattened cells; 4) cuboidal epidermis, located approximately 900 microns from the root pole and characterized by cuboidal cells having numerous small vacuoles; 5) vacuolate cuboidal epidermis, located approximately 1,500 microns from the root pole and characterized by cuboidal cells containing several large vacuoles; and 6) columnar epidermis, located approximately 2,200 microns from the root pole (i.e., at the beginning of the zone of elongation) and characterized by elongated cells. We also used stereology to quantify the cellular changes associated with epidermal differentiation. The quiescent center and the apical protoderm have significantly different ultrastructures. The relative volume of dictyosomes increases dramatically during the early stages of epidermal differentiation. This increase correlates inversely with the amount of coverage provided by the root cap and mucilage.

Effects of pea chips on pig performance, carcass quality and composition, and palatability of pork.

PubMed

Newman, D J; Harris, E K; Lepper, A N; Berg, E P; Stein, H H

2011-10-01

Pea chips are produced as a by-product when field peas are processed to produce split peas for human consumption. The objective of this experiment was to test the hypothesis that inclusion of pea chips in diets fed to finishing pigs does not negatively influence pig growth performance, carcass composition, and the palatability of pork. A total of 24 barrows (initial BW: 58.0 ± 6.6 kg) were allotted to 1 of 4 treatments and fed early finishing diets for 35 d and late finishing diets for 35 d. A corn-soybean meal (SBM) control diet and 3 diets containing pea chips were formulated for each phase. Pea chips replaced 33.3, 66.6, or 100% of the SBM in the control diet. Pigs were housed individually, and all pigs were slaughtered at the conclusion of the experiment. Overall, there were no differences (P > 0.11) in final BW, ADFI, and G:F of pigs among treatments, but there was a quadratic response in ADG (P = 0.04), with the smallest value observed in pigs fed the control diet. Dressing percentage linearly decreased (P = 0.04) as pea chips replaced SBM in diets, but there were no differences (P > 0.20) among treatments in HCW, LM area, 10th-rib backfat, lean meat percentage, and marbling. Likewise, pH in loin and ham, drip loss, and purge loss were not influenced (P > 0.13) by treatment. However, there was a quadratic response (P = 0.08) in 24-h pH in the shoulder, with the smallest value present in pigs fed the diet, in which 66.6% of the SBM was replaced by pea chips. Subjective LM color and Japanese color score standard were reduced (quadratic, P = 0.03 and 0.05, respectively) and LM b* values and hue angle were increased (quadratic, P = 0.09 and 0.10, respectively) when pea chips replaced SBM in the diets. Ham L* (quadratic, P = 0.04), a* (linear, P = 0.02), b* (quadratic, P = 0.07), color saturation (linear, P = 0.02), and hue angle (quadratic, P = 0.05) were increased when pea chips replaced SBM. However, there were no differences (P > 0.16) in shoulder and fat color. Moreover, cook loss percentage, shear force, juiciness, and pork flavor of pork chops were not different (P > 0.10) among treatments, but tenderness of pork chops linearly decreased (P = 0.04) as SBM replaced pea chips. It is concluded that all the SBM in diets fed to growing-finishing pigs may be replaced by pea chips without negatively influencing growth performance or carcass composition. However, pigs fed pea chips will have pork chops and hams that are lighter, and chops may be less tender if pigs are fed pea chips rather than corn and SBM.

Bowman-Birk inhibitor-like protein is secreted by sprouted pea seeds in response to induced colonization by enteropathogenic Escherichia coli.

PubMed

Anuradha, Ravi; Raveendran, Muthuraj; Babu, Subramanian

2013-11-01

The interaction between the clinical isolate of enteropathogenic Escherichia coli (EPEC) SBANU8 and pea sprouts was compared with avirulent K 12. E. coli. This was carried out by repeated co-incubation with pea sprouts for 5 days, and the protein profile of the culture supernatant was analyzed by single and two-dimensional electrophoresis. Mass spectrometry analysis led to the identification of two serine protease inhibitors including a Bowman-Birk-type protein secreted by pea sprouts in response to clinical isolate. Expression of the E. coli intimin gene involved in animal host colonization and virulence was studied by reverse transcription polymerase chain reaction. Expression of this gene was high in SBANU8 when co-incubated with pea sprouts. The present study gives baseline data on the molecular level interactions of EPEC and pea sprouts, which are needed to design the outbreak control strategies.

Replication of pea enation mosaic virus RNA in isolated pea nuclei

PubMed Central

Powell, C. A.; Zoeten, G. A. de

1977-01-01

Isolated nuclei from healthy pea plants were primed with pea enation mosaic virus (PEMV), southern bean mosaic virus (SBMV), radish mosaic virus (RdMV), tobacco mosaic virus (TMV), PEMV RNA, SBMV RNA, RdMV RNA, or TMV RNA. RNA replication occurred only with PEMV RNA and not with intact PEMV or any of the other viruses or RNAs, as judged by ensuing actinomycin D-insensitive polymerase activity. Molecular hybridization experiments showed that some of the product of the polymerase was PEMV-specific (-)RNA. The substrate and ionic requirements of this polymerase were the same as those for the RNA-dependent RNA polymerase present in nuclei isolated from PEMV-infected pea plants. No virus particles could be recovered from nuclei primed with PEMV RNA. These results are discussed in relation to the possible mechanism for in vivo infection of pea cells. PMID:16592421

Behavioral effects of β-phenylethylamine and various monomethylated and monohalogenated analogs in mice are mediated by catecholaminergic mechanisms.

PubMed

Mosnaim, Aron D; Hudzik, Thomas; Wolf, Marion E

2015-01-01

The effects of the administration [intraperitoneally, 15 and 75 mg/kg, except α-MePEA (amphetamine, AMPH) at 5 and 10 mg/kg] of β-phenylethylamine (PEA), its methylated (o-Me-, p-Me-, α-Me-, β-Me-, N-Me-, p-OMe-, N,N-di-Me-, and 3,4-diOH-N-Me-), para-halogenated (Br-, Cl-, F-, and I-), and other derivatives for example, p-OHPEA (p-tyramine), on Swiss male albino mice caged behavior fall into 3 broad categories. (1) N,N-diMe-, 3,4-diOH-N-Me-, and o-MePEA tend to reduce the behavioral activity, (2) p-OH and p-IPEA were without noticeable effects, and (3) the remaining compounds increased locomotor activity, produced hyperexcitability and fighting, jumping and vocalization, and convulsion in a graded manner (listed in increasing order p-OMe-, β-Me-, p-Cl-, p-Br-, p-F-, p-Me-, and N-MePEA, PEA itself and α-MePEA). The latter compound (amphetamine) being the most potent among them; equieffective but with lower potency were p-MePEA, N-MePEA, and PEA itself. The effects of PEAs upon group cage behavior were increased by pretreatment with pargyline (1.5 hours; 15 mg/kg) and decreased after reserpine or haloperidol [4 hours and/or 24 hours (2.5 and/or 2.5 mg/kg) and 1 hour (1 mg/kg), respectively], reaching full suppression with the double-dose regimen of reserpine and single dose of haloperidol. As expected, none of these substances by themselves were noticeable changed group mice activity or stereotypic behavior. The effects of test amines and catecholamine-modulating agents on stereotypy were assessed by rating the sequentially occurring behaviors: increased exploratory behavior with increased sniffing; occasional side-to-side head weaving; paw-licking and other grooming; gnawing, fighting and continuous side-to-side head weaving, and periodic episodes of "popcorn" behavior, during which all mice in the cage ran, jumped, and vocalized. In general, rank efficacy in eliciting stereotype aligned with rank efficacy in affecting group cage behavior. Our results show that a number of as yet little studied monomethylated and monohalogenated PEA analogs share a similar behavioral profile with PEA and AMPH. Behavioral changes observed appear to be, at least in part, mediated by catecholaminergic mechanism as they are modulated by drugs known to influence catecholamine activity. PEA analogs provide a large number of clinically useful drugs; whether further studies on these novel amines will lead to the rational design of newer, safer, and effective PEA-class drugs remains to be seen.

Induction of curvature in maize roots by calcium or by thigmostimulation: role of the postmitotic isodiametric growth zone

NASA Technical Reports Server (NTRS)

Ishikawa, H.; Evans, M. L.

1992-01-01

We examined the response of primary roots of maize (Zea mays L. cv Merit) to unilateral application of calcium with particular attention to the site of application, the dependence on growth rate, and possible contributions of thigmotropic stimulation during application. Unilateral application of agar to the root cap induced negative curvature whether or not the agar contained calcium. This apparent thigmotropic response was enhanced by including calcium in the agar. Curvature away from objects applied unilaterally to the extreme root tip occurred both in intact and detipped roots. When agar containing calcium chloride was applied to one side of the postmitotic isodiametric growth zone ( a region between the apical meristem and the elongation zone), the root curved toward the side of application. This response could not be induced by plain agar. We conclude that curvature away from calcium applied to the root tip results from a thigmotropic response to stimulation during application. In contrast, curvature toward the calcium applied to the postmitotic isodiametric growth zone results from direct calcium-induced inhibition of growth.

Factors affecting weld root morphology in laser keyhole welding

NASA Astrophysics Data System (ADS)

Frostevarg, Jan

2018-02-01

Welding production efficiency is usually optimised if full penetration can be achieved in a single pass. Techniques such as electron and laser beam welding offer deep high speed keyhole welding, especially since multi-kilowatt lasers became available. However, there are limitations for these techniques when considering weld imperfections such as weld cap undercuts, interior porosity or humps at the root. The thickness of sheets during full penetration welding is practically limited by these root humps. The mechanisms behind root morphology formation are not yet satisfactory understood. In this paper root humping is studied by reviewing previous studies and findings and also by sample examination and process observation by high speed imaging. Different process regimes governing root quality are presented, categorized and explained. Even though this study mainly covers laser beam and laser arc hybrid welding, the presented findings can generally be applied full penetration welding in medium to thick sheets, especially the discussion of surface tension effects. As a final result of this analysis, a map of methods to optimise weld root topology is presented.

Pea weevil damage and chemical characteristics of pea cultivars determining their resistance to Bruchus pisorum L.

PubMed

Nikolova, I

2016-04-01

Bruchus pisorum (L.) is one of the most intractable pest problems of cultivated pea in Europe. Development of resistant cultivars is very important to environmental protection and would solve this problem to a great extent. Therefore, the resistance of five spring pea cultivars was studied to B. pisorum: Glyans, Modus; Kamerton and Svit and Pleven 4 based on the weevil damage and chemical composition of seeds. The seeds were classified as three types: healthy seeds (type one), damaged seeds with parasitoid emergence holes (type two) and damaged seeds with bruchid emergence holes (type three). From visibly damaged pea seeds by pea weevil B. pisorum was isolated the parasitoid Triaspis thoracica Curtis (Hymenoptera, Braconidae). Modus, followed by Glyans was outlined as resistant cultivars against the pea weevil. They had the lowest total damaged seed degree, loss in weight of damaged seeds (type two and type three) and values of susceptibility coefficients. A strong negative relationship (r = -0.838) between the weight of type one seeds and the proportion of type three seeds was found. Cultivars with lower protein and phosphorus (P) content had a lower level of damage. The crude protein, crude fiber and P content in damaged seeds significantly or no significantly were increased as compared with the healthy seeds due to weevil damage. The P content had the highest significant influence on pea weevil infestation. Use of chemical markers for resistance to the creation of new pea cultivars can be effective method for defense and control against B. pisorum.

1. NORTHWEST OBLIQUE AERIAL VIEW OF FORT DELAWARE AND PEA ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. NORTHWEST OBLIQUE AERIAL VIEW OF FORT DELAWARE AND PEA PATCH ISLAND. REMAINS OF SEA WALL VISIBLE IN FOREGROUND AND RIGHT OF IMAGE. - Fort Delaware, Sea Wall, Pea Patch Island, Delaware City, New Castle County, DE

Beta-phenylethylamine inhibits K+ currents in neocortical neurons of the rat: a possible mechanism of beta-phenylethylamine-induced seizures.

PubMed

Kitamura, Taro; Munakata, Mitsutoshi; Haginoya, Kazuhiro; Tsuchiya, Shigeru; Iinuma, Kazuie

2008-08-01

beta-Phenylethylamine (beta-PEA), an endogenous amine synthesized in the brain, serves as a neuromodulator and is involved in the pathophysiology of various neurological disorders such as depression, schizophrenia, and attention-deficit hyperactivity disorder. beta-PEA fully exerts the physiological effects within the nanomolar concentration range via the trace amine receptors, but beta-PEA also causes convulsions at much higher concentrations via an as yet unknown mechanism. To investigate the electrophysiological mechanism by which beta-PEA induces convulsions, we examined the effect of beta-PEA on ionic currents passing through the cell membrane of dissociated rat cerebral cortical neurons, using a patch-clamp technique. The external application of beta-PEA suppressed ionic currents which continuously flowed when the membrane potential was held at -25 mV. The suppression was in a concentration-dependent manner and a half-maximal effective concentration was 540 muM. These currents suppressed by beta-PEA consisted of two K(+) currents: a time- and voltage-dependent K(+) current (M-current) and a leakage K(+) current. The suppression of the M-current reduces the efficacy of the current in limiting excessive neuronal firing, and the suppression of the leakage K(+) current can cause membrane depolarization and thus promote neuronal excitation. Reducing both of these currents in concert may produce neuronal seizing activity, which could conceivably underlie the convulsions induced by high-dose beta-PEA.

VizieR Online Data Catalog: Lyα profile in 43 Green Pea galaxies (Yang+, 2017)

NASA Astrophysics Data System (ADS)

Yang, H.; Malhotra, S.; Gronke, M.; Rhoads, J. E.; Leitherer, C.; Wofford, A.; Jiang, T.; Dijkstra, M.; Tilvi, V.; Wang, J.

2018-03-01

In SDSS DR7, a sample of 251 Green Peas was observed as serendipitous spectroscopic targets (Cardamone+ 2009MNRAS.399.1191C). A subset of 66 Green Peas have sufficient signal-to-noise ratio (S/N) in both continuum and emission lines (Hα, Hβ, and [OIII]λ5007) to study galactic properties. In Paper I (Yang+ 2016ApJ...820..130Y), we matched these 66 Green Peas with the COS archive and studied Lyα escape in a sample of 12 Green Peas with COS UV spectra. To address the bias and expand the sample size, we took the Lyα spectra of 20 additional Green Peas (PI S. Malhotra, GO 14201). We also supplement this sample with 11 additional Green Peas from published literature. In total, we have 43 Green Peas from six HST programs -- 20 galaxies from GO 14201 (PI S. Malhotra), 9 galaxies from GO 12928 (PI A. Henry; Henry+ 2015ApJ...809...19H), 7 galaxies from GO 11727 and GO 13017 (PI T. Heckman; Heckman+ 2011ApJ...730....5H ; Alexandroff+ 2015ApJ...810..104A), 2 galaxies from GO 13293 (PI A. Jaskot; Jaskot & Oey 2014ApJ...791L..19J), and 5 galaxies from GO 13744 (PI T. Thuan; Izotov+ 2016MNRAS.461.3683I). (4 data files).

Effects of pigeon pea and plantain starches on the compressional, mechanical, and disintegration properties of paracetamol tablets.

PubMed

Dare, Kunle; Akin-Ajani, Dorothy O; Odeku, Oluwatoyin A; Itiola, Oludele A; Odusote, Omotunde M

2006-03-01

A study has been made of the effects of pigeon pea starch obtained from the plant Cajanus cajan (L) Millisp. (family Fabaceae) and plantain starch obtained from the unripe fruit of Musa paradisiaca L. (family Musaceae) on the compressional, mechanical, and disintegration properties of paracetamol tablets in comparison with official corn starch BP. Analysis of compressional properties was done by using density measurements, and the Heckel and Kawakita equations, whereas the mechanical properties of the tablets were evaluated by using tensile strength (T--a measure of bond strength) and brittle fracture index (BFI--a measure of lamination tendency). The ranking for the mean yield pressure, P(y), for the formulations containing the different starches was generally corn < pigeon pea < plantain starch while the ranking for P(k), an inverse measure of the amount of plasticity, was pigeon pea < plantain < corn starch, which indicated that formulations containing corn starch generally exhibited the fastest onset of plastic deformation, whereas those formulations containing pigeon pea starch exhibited the highest amount of plastic deformation during tableting. The tensile strength of the tablets increased with increase in concentration of the starches while the Brittle Fracture Index decreased. The ranking for T was pigeon pea > plantain > corn starch while the ranking for BFI was corn > plantain > pigeon pea starch. The bonding capacity of the formulations was in general agreement with the tensile strength results. The disintegration time (DT) of the formulation increased with concentration of plantain and corn starches but decreased with concentration of pigeon pea starch. The general ranking of DT values was plantain < pigeon pea < corn starch. Notably, formulations containing pigeon pea starch exhibited the highest bond strength and lowest brittleness, suggesting the usefulness of pigeon pea starch in producing strong tablets with minimal lamination tendency. Plantain starch, on the other hand, would be more useful where faster disintegration of tablet is desired. The results show that the starches could be useful in various formulations depending on the intended use of the tablets with the implication that the experimental starches can be developed for commercial purposes.

Effective delivery of a nematode-repellent peptide using a root-cap-specific promoter.

PubMed

Lilley, Catherine J; Wang, Dong; Atkinson, Howard J; Urwin, Peter E

2011-02-01

The potential of the MDK4-20 promoter of Arabidopsis thaliana to direct effective transgenic expression of a secreted nematode-repellent peptide was investigated. Its expression pattern was studied in both transgenic Arabidopsis and Solanum tuberosum (potato) plants. It directed root-specific β-glucuronidase expression in both species that was chiefly localized to cells of the root cap. Use of the fluorescent timer protein dsRED-E5 established that the MDK4-20 promoter remains active for longer than the commonly used constitutive promoter CaMV35S in separated potato root border cells. Transgenic Arabidopsis lines that expressed the nematode-repellent peptide under the control of either AtMDK4-20 or CaMV35S reduced the establishment of the beet cyst nematode Heterodera schachtii. The best line using the AtMDK4-20 promoter displayed a level of resistance >80%, comparable to that of lines using the CaMV35S promoter. In transgenic potato plants, 94.9 ± 0.8% resistance to the potato cyst nematode Globodera pallida was achieved using the AtMDK4-20 promoter, compared with 34.4 ± 8.4% resistance displayed by a line expressing the repellent peptide from the CaMV35S promoter. These results establish the potential of the AtMDK4-20 promoter to limit expression of a repellent peptide whilst maintaining or even improving the efficacy of the cyst-nematode defence. © 2010 The Authors. Plant Biotechnology Journal © 2010 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.

Free radical development in phacoemulsification cataract surgery.

PubMed

Takahashi, Hiroshi

2005-02-01

Phacoemulsification and aspiration (PEA) has become the most popular cataract surgery, due to the establishment of safe surgical techniques and development of associated instruments. However, corneal endothelial damage still represents a serious complication, as excessive damage can lead to irreversible bullous keratopathy. In addition to causes such as mechanical or heat injuries, free radical formation due to ultrasound has been posited as another cause of corneal endothelium damage in PEA. Ultrasound in aqueous solution induces cavitation, directly causing water molecule disintegration and resulting in the formation of hydroxylradicals, the most potent of the reactive oxygen species. Considering the oxidative insult to endothelial cells caused by free radicals, their presence in the anterior chamber may represent one of the most harmful factors during these procedures. Indeed, some researchers have recently started to evaluate PEA from the perspective of oxidative stress. Conversely, the major ingredient in ophthalmic viscosurgical devices (OVDs), which are indispensable for maintaining the anterior chamber in PEA surgery, is sodium hyaluronate, a known free radical scavenger. OVDs can thus be expected to provide some anti-free radical effect during PEA procedures. In addition, since commercially available OVDs display different properties regarding retention in the anterior chamber during PEA, the anti-free radical effect of OVDs is likely to depend on behavior during irrigation and aspiration. The present study followed standard PEA procedures in an eye model and measured hydroxylradicals in the anterior chamber using electron spin resonance. The kinetics of free radical intensity and effects of several OVDs during clinical PEA were also demonstrated. These studies may be of significance in re-evaluating OVDs as a chemical protectant for corneal endothelium, since the OVD has thus far only been regarded as a physical barrier. In addition, many reports about corneal endothelium damage during PEA have been published, but objective evaluation of various damaging factors has been difficult. The present assay of free radicals in a simulation of clinical PEA offers the first method to quantitatively assess stress on the corneal endothelium.

Discrete forms of amylose are synthesized by isoforms of GBSSI in pea.

PubMed

Edwards, Anne; Vincken, Jean-Paul; Suurs, Luc C J M; Visser, Richard G F; Zeeman, Sam; Smith, Alison; Martin, Cathie

2002-08-01

Amyloses with distinct molecular masses are found in the starch of pea embryos compared with the starch of pea leaves. In pea embryos, a granule-bound starch synthase protein (GBSSIa) is required for the synthesis of a significant portion of the amylose. However, this protein seems to be insignificant in the synthesis of amylose in pea leaves. cDNA clones encoding a second isoform of GBSSI, GBSSIb, have been isolated from pea leaves. Comparison of GBSSIa and GBSSIb activities shows them to have distinct properties. These differences have been confirmed by the expression of GBSSIa and GBSSIb in the amylose-free mutant of potato. GBSSIa and GBSSIb make distinct forms of amylose that differ in their molecular mass. These differences in product specificity, coupled with differences in the tissues in which GBSSIa and GBSSIb are most active, explain the distinct forms of amylose found in different tissues of pea. The shorter form of amylose formed by GBSSIa confers less susceptibility to the retrogradation of starch pastes than the amylose formed by GBSSIb. The product specificity of GBSSIa could provide beneficial attributes to starches for food and nonfood uses.

Molecular cloning of isoflavone reductase from pea (Pisum sativum L.): evidence for a 3R-isoflavanone intermediate in (+)-pisatin biosynthesis.

PubMed

Paiva, N L; Sun, Y; Dixon, R A; VanEtten, H D; Hrazdina, G

1994-08-01

Isoflavone reductase (IFR) reduces achiral isoflavones to chiral isoflavanones during the biosynthesis of chiral pterocarpan phytoalexins. A cDNA clone for IFR from pea (Pisum sativum) was isolated using the polymerase chain reaction and expressed in Escherichia coli. Analysis of circular dichroism (CD) spectra of the reduction product sophorol obtained using the recombinant enzyme indicated that the isoflavanone possessed the 3R stereochemistry, in contrast to previous reports indicating a 3S-isoflavanone as the product of the pea IFR. Analysis of CD spectra of sophorol produced using enzyme extracts of CuCl2-treated pea seedlings confirmed the 3R stereochemistry. Thus, the stereochemistry of the isoflavanone intermediate in (+)-pisatin biosynthesis in pea is the same as that in (-)-medicarpin biosynthesis in alfalfa, although the final pterocarpans have the opposite stereochemistry. At the amino acid level the pea IFR cDNA was 91.8 and 85.2% identical to the IFRs from alfalfa and chickpea, respectively. IFR appears to be encoded by a single gene in pea. Its transcripts are highly induced in CuCl2-treated seedlings, consistent with the appearance of IFR enzyme activity and pisatin accumulation.

Oxidative processes in soybean and pea seeds: effect of light, temperature, and water content

NASA Technical Reports Server (NTRS)

Vertucci, C. W.; Leopold, A. C.

1987-01-01

Oxidative processes are probable determinants of longevity of seeds in storage. Measurements of actual oxygen uptake rates were made for soybean and pea seeds as a comparison of short and long lived seeds when light, temperature, and moisture contents were varied. In both peas and soybeans, the oxygen uptake was depressed at low temperatures (<16 degrees C) and low water contents (< 0.25 gram H2O per gram dry weight). Apparent activation energies under these conditions are very high, while apparent activation energies of seeds at higher water contents and at temperatures greater than 22 degrees C are much less. Light enhances the level of oxygen uptake in pea, but reduces the level of oxygen uptake in soybean. The complexities of the interactions of oxygen uptake with environmental conditions in soybean compared to pea suggest that oxidative processes occur in soybean at low water contents, but are essentially absent in pea. It is suggested that the additional oxidative processes in soybean with moisture contents between 0.10 and 0.24 gram per gram may contribute to the poorer longevity of soybean seed compared to pea seed.

Discrete Forms of Amylose Are Synthesized by Isoforms of GBSSI in PeaW⃞

PubMed Central

Edwards, Anne; Vincken, Jean-Paul; Suurs, Luc C. J. M.; Visser, Richard G. F.; Zeeman, Sam; Smith, Alison; Martin, Cathie

2002-01-01

Amyloses with distinct molecular masses are found in the starch of pea embryos compared with the starch of pea leaves. In pea embryos, a granule-bound starch synthase protein (GBSSIa) is required for the synthesis of a significant portion of the amylose. However, this protein seems to be insignificant in the synthesis of amylose in pea leaves. cDNA clones encoding a second isoform of GBSSI, GBSSIb, have been isolated from pea leaves. Comparison of GBSSIa and GBSSIb activities shows them to have distinct properties. These differences have been confirmed by the expression of GBSSIa and GBSSIb in the amylose-free mutant of potato. GBSSIa and GBSSIb make distinct forms of amylose that differ in their molecular mass. These differences in product specificity, coupled with differences in the tissues in which GBSSIa and GBSSIb are most active, explain the distinct forms of amylose found in different tissues of pea. The shorter form of amylose formed by GBSSIa confers less susceptibility to the retrogradation of starch pastes than the amylose formed by GBSSIb. The product specificity of GBSSIa could provide beneficial attributes to starches for food and nonfood uses. PMID:12172021

Response of Pea Varieties to Damage Degree of Pea Weevil, Bruchus pisorum L.

PubMed Central

Nikolova, Ivelina Mitkova

2016-01-01

A study was conducted to determine the response of five pea varieties (Pisum sativum L.) to damage degree of Bruchus pisorum: Glyans, Modus, Kamerton, and Svit (Ukrainian cultivars) and Pleven 4 (Bulgarian cultivar). The seeds were classified into three types: healthy seeds (type 1), damaged seeds with parasitoid emergence hole (type 2), and damaged seeds with bruchid emergence hole (type 3) and they were sown. It was found that the weight of 1000 seeds did not affect the field germination of the pea varieties. Healthy and damaged seeds with parasitoid emergence holes (first and second seed types) provide a very good opportunity for growth and development while plants from damaged seeds with bruchid emergence holes had poor germination and vigor and low productivity. These seeds cannot provide the creation of well-garnished seeding and stable crop yields. Among tested varieties, the Ukrainian variety Glyans had considerably higher seed weight, field germination, and index germination and weak egg-laying activity of B. pisorum compared to others. Use of spring pea cultivars that are weakly preferred by the pea weevil in breeding programs would reduce losses due to pea weevil and provide an environmentally safer option to its control. PMID:27042379

Plant Roots: The Hidden Half. Chapter 16; Calcium and Gravitropism; Revised

NASA Technical Reports Server (NTRS)

Poovaiah, B. W.; Reedy, A. S. N.

1995-01-01

Environmental signals such as light and gravity control many aspects of plant growth and development. In higher plants, the directional growth of an organ in response to stimuli such as gravity and light is considered a tropic movement. Such movement could be either positive or negative with respect to a specific stimulus. In general, stems show a positive response to light and negative response to gravity. In contrast, most roots show a positive response to gravity and a negative response to light. Investigations on plant tropism date back a century when Darwin studied the phototropic responses of maize seedlings (Darwin). Although the precise mechanism of signal perception and transduction in roots is not understood, Darwin recognized over 100 years ago that the root cap is the probable site of signal perception. He discovered that the removal of the root cap eliminates the ability of roots to respond to gravity. Other investigators have since confirmed Darwin's observation (Konings; Evans et al.). In recent years, especially with the advent of the U.S. Space Program, there has been a renewed interest in understanding how plants respond to extracellular signals such as gravity (Halstead and Dutcher). Studies on the mechanisms involved in perception and transduction of gravity signal by roots would ultimately help us to better understand gravitropism and also to grow plants under microgravity conditions as in space. In this chapter, we restrict ourselves to the role of calcium in transduction of the gravity signal. In doing so, emphasis is given to the role of calcium-modulated proteins and their role in signal transduction in gravitropism. Detailed reviews on various other aspects of gravitropism (Scott, Torrey, Wilkins, Fim and Digby, Feldman, Pickard, Moore and Evans, Halstead and Dutcher, Poovaiah et al.) and on the role of calcium as a messenger in signal transduction in general have been published (Helper and Wayne, Poovaiah and Reddy, Roberts and Hartnon, Bowler and Chua, Gilroy and Trewavas). Plant roots have been widely used to study the transduction of gravity and light signals (Poovaiah et al., Roux and Serlin). Most roots show positive gravitropic response in either dark or light. However, roots of some varieties of plants (e.g., Zea mays L., cv Merit, and Zea rwvs L., cv Golden Cross Bantam 70) show positive gravitropic response only in light (Feldman, Miyazaki et al.). Investigations from various laboratories indicate that calcium acts as a messenger in transducing gravity and light signals in plant roots(Pickard, Evans et al., Pooviah et al.).

40 CFR 180.574 - Fluazinam; tolerances for residues.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Ginseng 4.5 Lettuce, head 0.02 Lettuce, leaf 2.0 Onion, bulb, subgroup 3-07A 0.20 Pea and bean, dried shelled, except soybean, subgroup 6C, except pea 0.02 Pea and bean, succulent shelled, subgroup 6B, except...

Ersiphe trifolii-a newly recognized powdery mildew pathogen of pea.

USDA-ARS?s Scientific Manuscript database

Population diversity of powdery mildews infecting pea (Pisum sativum) in the US Pacific Northwest was investigated in order to assess inconsistent resistance performances of pea genotypes in different environments. Phylogenetic analyses based on ITS sequences, in combination with assessment of morph...

The cyclic nucleotide gated cation channel AtCNGC10 traffics from the ER via Golgi vesicles to the plasma membrane of Arabidopsis root and leaf cells.

PubMed

Christopher, David A; Borsics, Tamas; Yuen, Christen Y L; Ullmer, Wendy; Andème-Ondzighi, Christine; Andres, Marilou A; Kang, Byung-Ho; Staehelin, L Andrew

2007-09-19

The cyclic nucleotide-gated ion channels (CNGCs) maintain cation homeostasis essential for a wide range of physiological processes in plant cells. However, the precise subcellular locations and trafficking of these membrane proteins are poorly understood. This is further complicated by a general deficiency of information about targeting pathways of membrane proteins in plants. To investigate CNGC trafficking and localization, we have measured Atcngc5 and Atcngc10 expression in roots and leaves, analyzed AtCNGC10-GFP fusions transiently expressed in protoplasts, and conducted immunofluorescence labeling of protoplasts and immunoelectron microscopic analysis of high pressure frozen leaves and roots. AtCNGC10 mRNA and protein levels were 2.5-fold higher in roots than leaves, while AtCNGC5 mRNA and protein levels were nearly equal in these tissues. The AtCNGC10-EGFP fusion was targeted to the plasma membrane in leaf protoplasts, and lightly labeled several intracellular structures. Immunofluorescence microscopy with affinity purified CNGC-specific antisera indicated that AtCNGC5 and AtCNGC10 are present in the plasma membrane of protoplasts. Immunoelectron microscopy demonstrated that AtCNGC10 was associated with the plasma membrane of mesophyll, palisade parenchyma and epidermal cells of leaves, and the meristem, columella and cap cells of roots. AtCNCG10 was also observed in the endoplasmic reticulum and Golgi cisternae and vesicles of 50-150 nm in size. Patch clamp assays of an AtCNGC10-GFP fusion expressed in HEK293 cells measured significant cation currents. AtCNGC5 and AtCNGC10 are plasma membrane proteins. We postulate that AtCNGC10 traffics from the endoplasmic reticulum via the Golgi apparatus and associated vesicles to the plasma membrane. The presence of the cation channel, AtCNGC10, in root cap meristem cells, cell plate, and gravity-sensing columella cells, combined with the previously reported antisense phenotypes of decreased gravitropic and cell enlargement responses, suggest roles of AtCNGC10 in modulating cation balance required for root gravitropism, cell division and growth.

Quality evaluation of stiff porridges prepared from Irish potato (Solanum tuberosum) and pigeon pea (Cajanus cajan) starch blends.

PubMed

Abu, Joseph Oneh; Enyinnaya, Chinma Chiemela; James, Samaila; Okeleke, Ezinne

2012-06-01

Quality attributes of stiff porridges prepared from Irish potato and pigeon pea starch blends were studied. Starches were extracted from Irish potato and pigeon pea using a wet extraction method. Various ratios of the starches were mixed and analyzed for chemical, functional and pasting properties. The starch blends were then prepared into stiff porridges for sensory evaluation using a 20-man sensory panel. Substitution of Irish potato starch with pigeon pea starch led to increases in protein (0.15 to 1.2%), fat (0.26 to 0.56%) and ash (0.30 to 0.69%) while the amylose content of the starch blends decreased (from 23.8 to 18.4%) respectively. Functional properties such as bulk density (0.75 to 0.60 g/cm(3)), water absorption capacity (3.1 to 2.6 g water/ g sample) and dispersibility (58.6 to 42.7%) decreased significantly (P < 0.05) at the highest concentration (50%) of pigeon pea starch respectively. Pasting properties such as peak, breakdown, final and setback viscosities increased with increasing levels of pigeon pea starch while peak time and pasting temperature decreased. The sensory attributes of stiff porridges were not adversely affected by pigeon pea starch inclusion. Therefore it should be possible to incorporate up to 50% of low digestible pigeon pea starch into Irish potato starch from legumes such as pigeon pea as alternatives to cassava starch in the preparation of stiff porridges. Such porridges made from Irish potato and legume starches could provide additional incentive for individuals requiring decreased and or slow starch digestibility such as diabetics.

Nodulation, Nitrogen Fixation, and Hydrogen Oxidation by Pigeon Pea Bradyrhizobium spp. in Symbiotic Association with Pigeon Pea, Cowpea, and Soybean †

PubMed Central

Nautiyal, C. S.; Hegde, S. V.; van Berkum, P.

1988-01-01

The pigeon pea strains of Bradyrhizobium CC-1, CC-8, UASGR(S), and F4 were evaluated for nodulation, effectiveness for N2 fixation, and H2 oxidation with homologous and nonhomologous host plants. Strain CC-1 nodulated Macroptilium atropurpureum, Vigna unguiculata, Glycine max, and G. soja but did not nodulate Pisum sativum, Phaseolus vulgaris, Trigonella foenum-graecum, and Trifolium repens. Strain F4 nodulated G. max cv. Peking and PI 434937 (Malayan), but the symbioses formed were poor. Similarly, G. max cv. Peking, cv. Bragg, PI 434937, PR 13-28-2-8-7, and HM-1 were nodulated by strain CC-1, and symbioses were also poor. G. max cv. Williams and cv. Clark were not nodulated. H2 uptake activity was expressed with pigeon pea and cowpea, but not with soybean. G. max cv. Bragg grown in Bangalore, India, in local soil not previously exposed to Bradyrhizobium japonicum formed nodules with indigenous Bradyrhizobium spp. Six randomly chosen isolates, each originating from a different nodule, formed effective symbioses with pigeon pea host ICPL-407, nodulated PR 13-28-2-8-7 soybean forming moderately effective symbioses, and did not nodulate Williams soybean. These results indicate the six isolates to be pigeon pea strains although they originated from soybean nodules. Host-determined nodulation of soybean by pigeon pea Bradyrhizobium spp. may depend upon the ancestral backgrounds of the cultivars. The poor symbioses formed by the pigeon pea strains with soybean indicate that this crop should be inoculated with B. japonicum for its cultivation in soils containing only pigeon pea Bradyrhizobium spp. PMID:16347542

Ly α and UV Sizes of Green Pea Galaxies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Huan; Wang, Junxian; Malhotra, Sangeeta

Green Peas are nearby analogs of high-redshift Ly α -emitting galaxies (LAEs). To probe their Ly α escape, we study the spatial profiles of Ly α and UV continuum emission of 24 Green Pea galaxies using the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope . We extract the spatial profiles of Ly α emission from their 2D COS spectra, and of the UV continuum from both 2D spectra and NUV images. The Ly α emission shows more extended spatial profiles than the UV continuum, in most Green Peas. The deconvolved full width at half maximum of the Lymore » α spatial profile is about 2–4 times that of the UV continuum, in most cases. Because Green Peas are analogs of high z LAEs, our results suggest that most high- z LAEs probably have larger Ly α sizes than UV sizes. We also compare the spatial profiles of Ly α photons at blueshifted and redshifted velocities in eight Green Peas with sufficient data quality, and find that the blue wing of the Ly α line has a larger spatial extent than the red wing in four Green Peas with comparatively weak blue Ly α line wings. We show that Green Peas and MUSE z = 3–6 LAEs have similar Ly α and UV continuum sizes, which probably suggests that starbursts in both low- z and high- z LAEs drive similar gas outflows illuminated by Ly α light. Five Lyman continuum (LyC) leakers in this sample have similar Ly α to UV continuum size ratios (∼1.4–4.3) to the other Green Peas, indicating that their LyC emissions escape through ionized holes in the interstellar medium.« less

PEA: an integrated R toolkit for plant epitranscriptome analysis.

PubMed

Zhai, Jingjing; Song, Jie; Cheng, Qian; Tang, Yunjia; Ma, Chuang

2018-05-29

The epitranscriptome, also known as chemical modifications of RNA (CMRs), is a newly discovered layer of gene regulation, the biological importance of which emerged through analysis of only a small fraction of CMRs detected by high-throughput sequencing technologies. Understanding of the epitranscriptome is hampered by the absence of computational tools for the systematic analysis of epitranscriptome sequencing data. In addition, no tools have yet been designed for accurate prediction of CMRs in plants, or to extend epitranscriptome analysis from a fraction of the transcriptome to its entirety. Here, we introduce PEA, an integrated R toolkit to facilitate the analysis of plant epitranscriptome data. The PEA toolkit contains a comprehensive collection of functions required for read mapping, CMR calling, motif scanning and discovery, and gene functional enrichment analysis. PEA also takes advantage of machine learning technologies for transcriptome-scale CMR prediction, with high prediction accuracy, using the Positive Samples Only Learning algorithm, which addresses the two-class classification problem by using only positive samples (CMRs), in the absence of negative samples (non-CMRs). Hence PEA is a versatile epitranscriptome analysis pipeline covering CMR calling, prediction, and annotation, and we describe its application to predict N6-methyladenosine (m6A) modifications in Arabidopsis thaliana. Experimental results demonstrate that the toolkit achieved 71.6% sensitivity and 73.7% specificity, which is superior to existing m6A predictors. PEA is potentially broadly applicable to the in-depth study of epitranscriptomics. PEA Docker image is available at https://hub.docker.com/r/malab/pea, source codes and user manual are available at https://github.com/cma2015/PEA. chuangma2006@gmail.com. Supplementary data are available at Bioinformatics online.

Lyα and UV Sizes of Green Pea Galaxies

NASA Astrophysics Data System (ADS)

Yang, Huan; Malhotra, Sangeeta; Rhoads, James E.; Leitherer, Claus; Wofford, Aida; Jiang, Tianxing; Wang, Junxian

2017-03-01

Green Peas are nearby analogs of high-redshift Lyα-emitting galaxies (LAEs). To probe their Lyα escape, we study the spatial profiles of Lyα and UV continuum emission of 24 Green Pea galaxies using the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope. We extract the spatial profiles of Lyα emission from their 2D COS spectra, and of the UV continuum from both 2D spectra and NUV images. The Lyα emission shows more extended spatial profiles than the UV continuum, in most Green Peas. The deconvolved full width at half maximum of the Lyα spatial profile is about 2-4 times that of the UV continuum, in most cases. Because Green Peas are analogs of high z LAEs, our results suggest that most high-z LAEs probably have larger Lyα sizes than UV sizes. We also compare the spatial profiles of Lyα photons at blueshifted and redshifted velocities in eight Green Peas with sufficient data quality, and find that the blue wing of the Lyα line has a larger spatial extent than the red wing in four Green Peas with comparatively weak blue Lyα line wings. We show that Green Peas and MUSE z = 3-6 LAEs have similar Lyα and UV continuum sizes, which probably suggests that starbursts in both low-z and high-z LAEs drive similar gas outflows illuminated by Lyα light. Five Lyman continuum (LyC) leakers in this sample have similar Lyα to UV continuum size ratios (˜1.4-4.3) to the other Green Peas, indicating that their LyC emissions escape through ionized holes in the interstellar medium.

Requirement of PEA3 for Transcriptional Activation of FAK Gene in Tumor Metastasis

PubMed Central

Li, Shufeng; Huang, Xiaofeng; Zhang, Dapeng; Huang, Qilai; Pei, Guoshun; Wang, Lixiang; Jiang, Wenhui; Hu, Qingang; Tan, Renxiang; Hua, Zi-Chun

2013-01-01

Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase critically involved in cancer metastasis. We found an elevation of FAK expression in highly metastatic melanoma B16F10 cells compared with its less metastatic partner B16F1 cells. Down-regulation of the FAK expression by either small interfering RNA or dominant negative FAK (FAK Related Non-Kinase, FRNK) inhibited the B16F10 cell migration in vitro and invasiveness in vivo. The mechanism by which FAK activity is up-regulated in highly metastatic cells remains unclear. In this study, we reported for the first time that one of the Est family proteins, PEA3, is able to transactivate FAK expression through binding to the promoter region of FAK. We identified a PEA3-binding site between nucleotides −170 and +43 in the FAK promoter that was critical for the responsiveness to PEA3. A stronger affinity of PEA3 to this region contributed to the elevation of FAK expression in B16F10 cells. Both in vitro and in vivo knockdown of PEA3 gene successfully mimicked the cell migration and invasiveness as that induced by FAK down-regulation. The activation of the well-known upstream of PEA3, such as epidermal growth factor, JNK, and ERK can also induce FAK expression. Furthermore, in the metastatic human clinic tumor specimens from the patients with human primary oral squamous cell carcinoma, we observed a strong positive correlation among PEA3, FAK, and carcinoma metastasis. Taking together, we hypothesized that PEA3 might play an essential role in the activation of the FAK gene during tumor metastasis. PMID:24260201

Response of Ca2+-ATPase to clinorotaion of pea seedlings. O. M. Nedukha and E. L. Kordyum

NASA Astrophysics Data System (ADS)

Nedukha, Olena

2016-07-01

The present study was aimed to reveal of response of Ca2+-ATPase activity of cortex cells in distal elongation zone of Pisum sativum root to slow clinorotation. Pea seedlings were grown on a horizontal clinostat (2 rpm) and in the stationary control for 6 days. The electron-cytochemical method was used to examine the effects of imitated microgravity on the distribution of Ca2+-ATPase in outer layers of root cortex. The quantitative analysis of the density of cytochemical reaction products was measured using the Image J program. Electron microscopy showed the presence of electron-dense lead phosphate precipitated grains, the enzymatic activity reaction products on the plasma membrane, membranes of vesicular structures, endoplasmic reticulum (ER) and on organelles envelope in both of samples of the stationary control and clinorotated seedlings. We revealed the sensitivity of Ca2+-ATPase to clinorotation. The quantitative analysis of the area and density of enzymatic activity reaction products revealed that clinorotation led to the decrease of 3.4 times the density of reaction products on the plasma membrane and the increase of reaction products density on endomembranes and organelles membranes, in particular: in 2.2 times on mitochondria membranes; in 1.3 times - on membranes of ER; in 2.5 times - on tonoplast; by an order of magnitude greater - on contacting membranes of organelles with plasma membrane in comparison with such in cells of control samples. The data analysis can indicate an intensification of calcium pump on endomembranes, on envelopes of cytoplasmic organelles and nucleus. The obtained data suggest that the redistribution of Ca2+-ATPase activity in cells can be mediated by the activation of certain isoforms of enzyme or/and by an activation of Ca2+/H+ antiporter in plasma membrane that helps to maintain optimal calcium balance in plant cells under imitated microgravity.

Arginine-based poly(ester amide) nanoparticle platform: From structure-property relationship to nucleic acid delivery.

PubMed

You, Xinru; Gu, Zhipeng; Huang, Jun; Kang, Yang; Chu, Chih-Chang; Wu, Jun

2018-05-25

Many different types of polycations have been vigorously studied for nucleic acid delivery, but a systematical investigation of the structure-property relationships of polycations for nucleic acid delivery is still lacking. In this study, a new library of biodegradable and biocompatible arginine-based poly(ester amide) (Arg-PEA) biomaterials was designed and synthesized with a tunable structure for such a comprehensive structure-property research. Nanoparticle (NP) complexes were formed through the electrostatic interactions between the polycationic Arg-PEAs and anionic nucleic acids. The following structure effects of the Arg-PEAs on the transfection efficiency of nucleic acids were investigated: 1) the linker/spacer length (length effect and odd-even effect); 2) salt type of arginine; 3) the side chain; 4) chain stiffness; 5) molecular weight (MW). The data obtained revealed that a slight change in the Arg-PEA structure could finely tune its physicochemical property such as hydrophobicity, and this could subsequently affect the nanoparticle size and zeta potential, which, in turn, regulate the transfection efficiency and silencing outcomes. A further study of the Arg-PEA/CpG oligodeoxynucleotide NP complexes indicated that the polymer structure could precisily regulate the immune response of CpG, thus providing a new potential nano-immunotherapy strategy. The in vitro data have further confirmed that the Arg-PEA NPs showed a satisfactory delivery performance for a variety of nucleic acids. Therefore, the data from the current study provide comprehensive information about the Arg-PEA structure-transfection property relationship; the tunable property of the library of Arg-PEA biomaterials can be one of the promising candidates for nucleic acid delivery and other biomedical applications. Polycations have being intensive utilized for nucleic acid delivery. However, there has not been elucidated about the relationship between polycation's structure and the physicochemical properties/biological function. In this timely report, an arginine based poly(ester amide) (Arg-PEA) library was prepared with finely tunable structure to systematically investigate the structure-property relationships of polycations for nucleic acid delivery. The results revealed that slight change of Arg-PEA structure could finely tune the physicochemical property (such as hydrophobicity), which subsequently affect the size and zeta potential of Arg-PEA/nucleic acid nanoparticles(NPs), and finally regulate the resulting transfection or silencing outcomes. Further study of Arg-PEA/CpG NPs indicated that the polymer structure could precisely regulate immuno response of CpG, providing new potential nano-immunotherapy strategy. In vitro evaluations confirmed that the NPs showed satisfied delivery performance for a variety types of nucleic acids. Therefore, these studies provide comprehensive information of Arg-PEA structure-property relationship, and the tunable properties of Arg-PEAs make them promising candidates for nucleic acid delivery and other biomedical applications. Overall, we have shown enough significance and novelty in terms of nucleic acid delivery, biomaterials, pharmaceutical science and nanomedicine. Copyright © 2018. Published by Elsevier Ltd.

Ruthenium (Ru) peeling and predicting robustness of the capping layer using finite element method (FEM) modeling

NASA Astrophysics Data System (ADS)

Jang, Il-Yong; John, Arun; Goodwin, Frank; Lee, Su-Young; Kim, Byung-Gook; Kim, Seong-Sue; Jeon, Chan-Uk; Kim, Jae Hyung; Jang, Yong Hoon

2014-07-01

Ruthenium (Ru) film used as capping layer in extreme ultraviolet (EUV) mask peeled off after annealing and in-situ UV (IUV) cleaning. We investigated Ru peeling and found out that the mechanical stress caused by the formation of Si oxide due to the penetration of oxygen atoms from ambient or cleaning media to top-Si of ML is the root cause for the problem. To support our experimental results, we developed a numerical model of finite element method (FEM) using commercial software (ABAQUS™) to calculate the stress and displacement forced on the capping layer. By using this model, we could observe that the displacement agrees well with the actual results measured from the transmission electron microscopy (TEM) image. Using the ion beam deposition (IBD) tool at SEMATECH, we developed four new types of alternative capping materials (RuA, RuB, B4C, B4C-buffered Ru). The durability of each new alternative capping layer observed by experiment was better than that of conventional Ru. The stress and displacement calculated from each new alternative capping layer, using modeling, also agreed well with the experimental results. A new EUV mask structure is proposed, inserting a layer of B4C (B4C-buffered Ru) at the interface between the capping layer (Ru) and the top-Si layer. The modeling results showed that the maximum displacement and bending stress observed from the B4C-buffered Ru are significantly lower than that of single capping layer cases. The durability investigated from the experiment also showed that the B4C-buffered structure is at least 3X stronger than that of conventional Ru.

Microgravity mediated changes in phytoferritin accumulation in soybean root cap cells

NASA Technical Reports Server (NTRS)

Klymchuk, D. O.; Kordyum, E. L.; Vorobyova, T. V.; Brown, C. S.; Chapman, D. K.

2000-01-01

Phytoferritin is an iron-protein complex analogous to the ferritin found in mammalian, bacteria and fungi cells. Phytoferritin molecules are large proteins, about 10.5 nm in diameter, visualised in an electron microscope as discrete, electron dense particles with iron-containing core, where several thousand atoms of iron lie within the proteinaceous shell (apoferritin). In higher plants, a plastid stroma is the site of phytoferritin storage. Phytoferritin is seen in all types of plastids. It is considered to be a mechanism used by cells to store iron in a non-toxic form. Phytoferritin-bound iron may subsequently be used to form iron-containing components. It was shown that low levels of phytoferritin are synthesised in normal green leaves, whereas chlorotic leaves do not have a measurable amount of phytoferritin and leaves of iron-loaded seedlings contain a high level of total iron, and phytoferritin well-filled by iron. Phytoferritin accumulation was observed in photosynthetic inactivity chloroplasts during senescence and disease. In this study we analised the effects of microgravity and ethylene on production of phytoferritin in the root cap columella cells of soybean seedlings.

Yield potential of pigeon pea cultivars

USDA-ARS?s Scientific Manuscript database

Yield potential of twelve vegetable pigeon pea (Cajanus cajun) cultivars was evaluated at two locations in eastern Kenya during 2012 and 2013 cropping years. Pigeon pea pod numbers, seeds per pod, seed mass, grain yield and shelling percentage were quantified in three replicated plots, arranged in a...

Cloning and characterization of TPE4A, a thiol-protease gene induced during ovary senescence and seed germination in pea.

PubMed

Cercós, M; Santamaría, S; Carbonell, J

1999-04-01

A cDNA clone encoding a thiol-protease (TPE4A) was isolated from senescent ovaries of pea (Pisum sativum) by reverse transcriptase-polymerase chain reaction. The deduced amino acid sequence of TPE4A has the conserved catalytic amino acids of papain. It is very similar to VSCYSPROA, a thiol-protease induced during seed germination in common vetch. TPE4A mRNA levels increase during the senescence of unpollinated pea ovaries and are totally suppressed by treatment with gibberellic acid. In situ hybridization indicated that TPE4A mRNA distribution in senescent pea ovaries is different from that of previously reported thiol-proteases induced during senescence, suggesting the involvement of different proteases in the mobilization of proteins from senescent pea ovaries. TPE4A is also induced during the germination of pea seeds, indicating that a single protease gene can be induced during two different physiological processes, senescence and germination, both of which require protein mobilization.

Probabilistic Exposure Analysis for Chemical Risk Characterization

PubMed Central

Bogen, Kenneth T.; Cullen, Alison C.; Frey, H. Christopher; Price, Paul S.

2009-01-01

This paper summarizes the state of the science of probabilistic exposure assessment (PEA) as applied to chemical risk characterization. Current probabilistic risk analysis methods applied to PEA are reviewed. PEA within the context of risk-based decision making is discussed, including probabilistic treatment of related uncertainty, interindividual heterogeneity, and other sources of variability. Key examples of recent experience gained in assessing human exposures to chemicals in the environment, and other applications to chemical risk characterization and assessment, are presented. It is concluded that, although improvements continue to be made, existing methods suffice for effective application of PEA to support quantitative analyses of the risk of chemically induced toxicity that play an increasing role in key decision-making objectives involving health protection, triage, civil justice, and criminal justice. Different types of information required to apply PEA to these different decision contexts are identified, and specific PEA methods are highlighted that are best suited to exposure assessment in these separate contexts. PMID:19223660

Hypocholesterolaemic effects of lupin protein and pea protein/fibre combinations in moderately hypercholesterolaemic individuals.

PubMed

Sirtori, Cesare R; Triolo, Michela; Bosisio, Raffaella; Bondioli, Alighiero; Calabresi, Laura; De Vergori, Viviana; Gomaraschi, Monica; Mombelli, Giuliana; Pazzucconi, Franco; Zacherl, Christian; Arnoldi, Anna

2012-04-01

The present study was aimed to evaluate the effect of plant proteins (lupin protein or pea protein) and their combinations with soluble fibres (oat fibre or apple pectin) on plasma total and LDL-cholesterol levels. A randomised, double-blind, parallel group design was followed: after a 4-week run-in period, participants were randomised into seven treatment groups, each consisting of twenty-five participants. Each group consumed two bars containing specific protein/fibre combinations: the reference group consumed casein+cellulose; the second and third groups consumed bars containing lupin or pea proteins+cellulose; the fourth and fifth groups consumed bars containing casein and oat fibre or apple pectin; the sixth group and seventh group received bars containing combinations of pea protein and oat fibre or apple pectin, respectively. Bars containing lupin protein+cellulose ( - 116 mg/l, - 4·2%), casein+apple pectin ( - 152 mg/l, - 5·3%), pea protein+oat fibre ( - 135 mg/l, - 4·7%) or pea protein+apple pectin ( - 168 mg/l, - 6·4%) resulted in significant reductions of total cholesterol levels (P<0·05), whereas no cholesterol changes were observed in the subjects consuming the bars containing casein+cellulose, casein+oat fibre or pea protein+cellulose. The present study shows the hypocholesterolaemic activity and potential clinical benefits of consuming lupin protein or combinations of pea protein and a soluble fibre, such as oat fibre or apple pectin.

Contribution of β-phenethylamine, a component of chocolate and wine, to dopaminergic neurodegeneration: implications for the pathogenesis of Parkinson's disease.

PubMed

Borah, Anupom; Paul, Rajib; Mazumder, Muhammed Khairujjaman; Bhattacharjee, Nivedita

2013-10-01

While the cause of dopaminergic neuronal cell death in Parkinson's disease (PD) is not yet understood, many endogenous molecules have been implicated in its pathogenesis. β-phenethylamine (β-PEA), a component of various food items including chocolate and wine, is an endogenous molecule produced from phenylalanine in the brain. It has been reported recently that long-term administration of β-PEA in rodents causes neurochemical and behavioral alterations similar to that produced by parkinsonian neurotoxins. The toxicity of β-PEA has been linked to the production of hydroxyl radical ((·)OH) and the generation of oxidative stress in dopaminergic areas of the brain, and this may be mediated by inhibition of mitochondrial complex-I. Another significant observation is that administration of β-PEA to rodents reduces striatal dopamine content and induces movement disorders similar to those of parkinsonian rodents. However, no reports are available on the extent of dopaminergic neuronal cell death after administration of β-PEA. Based on the literature, we set out to establish β-PEA as an endogenous molecule that potentially contributes to the progressive development of PD. The sequence of molecular events that could be responsible for dopaminergic neuronal cell death in PD by consumption of β-PEA-containing foods is proposed here. Thus, long-term over-consumption of food items containing β-PEA could be a neurological risk factor having significant pathological consequences.

The neuroprotective properties of palmitoylethanolamine against oxidative stress in a neuronal cell line

PubMed Central

2009-01-01

Background N-acylethanolamines (NAEs) are lipids upregulated in response to cell and tissue injury and are involved in cytoprotection. Arachidonylethanolamide (AEA) is a well characterized NAE that is an endogenous ligand at cannabinoid and vanilloid receptors, but it exists in small quantities relative to other NAE types. The abundance of other NAE species, such as palmitoylethanolamine (PEA), together with their largely unknown function and receptors, has prompted us to examine the neuroprotective properties and mechanism of action of PEA. We hypothesized that PEA protects HT22 cells from oxidative stress and activates neuroprotective kinase signaling pathways. Results Indeed PEA protected HT22 cells from oxidative stress in part by mediating an increase in phosphorylated Akt (pAkt) and ERK1/2 immunoreactivity as well as pAkt nuclear translocation. These changes take place within a time frame consistent with neuroprotection. Furthermore, we determined that changes in pAkt immunoreactivity elicited by PEA were not mediated by activation of cannabinoid receptor type 2 (CB2), thus indicating a novel mechanism of action. These results establish a role for PEA as a neuroprotectant against oxidative stress, which occurs in a variety of neurodegenerative diseases. Conclusions The results from this study reveal that PEA protects HT22 cells from oxidative stress and alters the localization and expression levels of kinases known to be involved in neuroprotection by a novel mechanism. Overall, these results identify PEA as a neuroprotectant with potential as a possible therapeutic agent in neurodegenerative diseases involving oxidative stress. PMID:20003317

Changes in the C/N balance caused by increasing external ammonium concentrations are driven by carbon and energy availabilities during ammonium nutrition in pea plants: the key roles of asparagine synthetase and anaplerotic enzymes.

PubMed

Ariz, Idoia; Asensio, Aaron C; Zamarreño, Angel M; García-Mina, Jose M; Aparicio-Tejo, Pedro M; Moran, Jose F

2013-08-01

An understanding of the mechanisms underlying ammonium (NH(4)(+)) toxicity in plants requires prior knowledge of the metabolic uses for nitrogen (N) and carbon (C). We have recently shown that pea plants grown at high NH(4)(+) concentrations suffer an energy deficiency associated with a disruption of ionic homeostasis. Furthermore, these plants are unable to adequately regulate internal NH4(+) levels and the cell-charge balance associated with cation uptake. Herein we show a role for an extra-C application in the regulation of C-N metabolism in NH(4)(+) -fed plants. Thus, pea plants (Pisum sativum) were grown at a range of NH(4)(+) concentrations as sole N source, and two light intensities were applied to vary the C supply to the plants. Control plants grown at high NH(4)(+) concentration triggered a toxicity response with the characteristic pattern of C-starvation conditions. This toxicity response resulted in the redistribution of N from amino acids, mostly asparagine, and lower C/N ratios. The C/N imbalance at high NH(4)(+) concentration under control conditions induced a strong activation of root C metabolism and the upregulation of anaplerotic enzymes to provide C intermediates for the tricarboxylic acid cycle. A high light intensity partially reverted these C-starvation symptoms by providing higher C availability to the plants. The extra-C contributed to a lower C4/C5 amino acid ratio while maintaining the relative contents of some minor amino acids involved in key pathways regulating the C/N status of the plants unchanged. C availability can therefore be considered to be a determinant factor in the tolerance/sensitivity mechanisms to NH(4)(+) nutrition in plants. Copyright © Physiologia Plantarum 2012.

Growth Chambers on the International Space Station for Large Plants

NASA Technical Reports Server (NTRS)

Massa, Gioia D.; Wheeler, Raymond M.; Morrow, Robert C.; Levine, Howard G.

2016-01-01

The International Space Station (ISS) now has platforms for conducting research on horticultural plant species under LED (Light Emitting Diodes) lighting, and those capabilities continue to expand. The Veggie vegetable production system was deployed to the ISS as an applied research platform for food production in space. Veggie is capable of growing a wide array of horticultural crops. It was designed for low power usage, low launch mass and stowage volume, and minimal crew time requirements. The Veggie flight hardware consists of a light cap containing red (630 nanometers), blue, (455 nanometers) and green (530 nanometers) LEDs. Interfacing with the light cap is an extendable bellowsbaseplate for enclosing the plant canopy. A second large plant growth chamber, the Advanced Plant Habitat (APH), is will fly to the ISS in 2017. APH will be a fully controllable environment for high-quality plant physiological research. APH will control light (quality, level, and timing), temperature, CO2, relative humidity, and irrigation, while scrubbing any cabin or plant-derived ethylene and other volatile organic compounds. Additional capabilities include sensing of leaf temperature and root zone moisture, root zone temperature, and oxygen concentration. The light cap will have red (630 nm), blue (450 nm), green (525 nm), far red (730 nm) and broad spectrum white LEDs (4100K). There will be several internal cameras (visible and IR) to monitor and record plant growth and operations. Veggie and APH are available for research proposals.

Crystallographic Texture and Elemental Composition Mapped in Bovine Root Dentin at the 200 nm Level

PubMed Central

Deymier-Black, A. C.; Veis, A.; Cai, Z.; Stock, S. R.

2015-01-01

Summary The relationship between the mineralization of peritubular dentin (PTD) and intertubular dentin (ITD) is not well understood. Tubules are quite small, diameter ~2 μm, and this makes the near-tubule region of dentin difficult to study. Here, advanced characterization techniques are applied in a novel way to examine what organic or nanostructural signatures may indicate the end of ITD or the beginning of PTD mineralization. X-ray fluorescence intensity (Ca, P, and Zn) and X-ray diffraction patterns from carbonated apatite (cAp) were mapped around dentintubules at resolutions ten times smaller than the feature size (200 nm pixels), representing a 36% increase in resolution over earlier work. In the near tubule volumes of near-pulp, root dentin, Zn intensity was higher than in ITD remote from the tubules. This increase in Zn2+, as determined by X-ray absorption near edge structure analysis, may indicate the presence of metalloenzymes or transcription factors important to ITD or PTD mineralization. The profiles of the cAp 00.2 X-ray diffraction rings were fitted with a pseudo-Voigt function, and the spatial and azimuthal distribution of these rings’ integrated intensities indicated that the cAp platelets were arranged with their c-axes aligned tangential to the edge of the tubule lumen. This texture was continuous throughout the dentin indicating a lack of structural difference between in the Zn rich near-tubular region and the remote ITD. PMID:23630059

7 CFR 457.140 - Dry pea crop insurance provisions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 6 2010-01-01 2010-01-01 false Dry pea crop insurance provisions. 457.140 Section 457.140 Agriculture Regulations of the Department of Agriculture (Continued) FEDERAL CROP INSURANCE CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.140 Dry pea crop insurance...

7 CFR 457.137 - Green pea crop insurance provisions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 6 2010-01-01 2010-01-01 false Green pea crop insurance provisions. 457.137 Section 457.137 Agriculture Regulations of the Department of Agriculture (Continued) FEDERAL CROP INSURANCE CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.137 Green pea crop insurance...

21 CFR 155.170 - Canned peas.

Code of Federal Regulations, 2014 CFR

2014-04-01

... the pea plant of the species Pisum sativum L. but excluding the subspecies macrocarpum. Only sweet... any combination of two or more of the dry or liquid forms of sugar, invert sugar sirup, dextrose... characteristics. Where the peas are of sweet green wrinkled varieties or hybrids having similar characteristics...

21 CFR 155.170 - Canned peas.

Code of Federal Regulations, 2012 CFR

2012-04-01

... the pea plant of the species Pisum sativum L. but excluding the subspecies macrocarpum. Only sweet... any combination of two or more of the dry or liquid forms of sugar, invert sugar sirup, dextrose... characteristics. Where the peas are of sweet green wrinkled varieties or hybrids having similar characteristics...

21 CFR 155.170 - Canned peas.

Code of Federal Regulations, 2013 CFR

2013-04-01

... the pea plant of the species Pisum sativum L. but excluding the subspecies macrocarpum. Only sweet... any combination of two or more of the dry or liquid forms of sugar, invert sugar sirup, dextrose... characteristics. Where the peas are of sweet green wrinkled varieties or hybrids having similar characteristics...

Genetic analysis of streptomycin-resistant (Sm(R)) strains of Erwinia amylovora suggests that dissemination of two genotypes is responsible for the current distribution of Sm(R) E. amylovora in Michigan.

PubMed

McGhee, Gayle C; Guasco, Jesse; Bellomo, Lisa M; Blumer-Schuette, Sara E; Shane, William W; Irish-Brown, Amy; Sundin, George W

2011-02-01

Streptomycin-resistant (Sm(R)) strains of the fire blight pathogen Erwinia amylovora were first isolated in southwest Michigan in 1991. Since that time, resistant strains have progressed northward to other apple-producing regions in the state. A total of 98.7% of Sm(R) strains isolated between 2003 and 2009 in Michigan harbored the strA-strB genes on transposon Tn5393. strA and strB encode phosphotransferase enzymes that modify streptomycin to a nonbactericidal form. Mutational resistance to streptomycin, caused by a point mutation-mediated target-site alteration of the ribosomal S12 protein, occurred in 1.3% of E. amylovora strains from Michigan. Tn5393 was originally introduced to E. amylovora on the plasmid pEa34; thus, the first Sm(R) strains isolated contained both pEa34 and the ubiquitous nonconjugative plasmid pEA29. More recently, we have observed Sm(R) strains in which Tn5393 is present on pEA29, suggesting that the transposon has moved via transposition from pEa34 to pEA29. Almost all of the strains containing Tn5393 on pEA29 had lost pEa34. Of 210 pEA29::Tn5393 plasmids examined, the transposon was inserted at either nucleotide position 1,515 or 17,527. Both of these positions were in noncoding regions of pEA29. Comparative sequencing of the housekeeping genes groEL and potentially variable sequences on pEA29 was done in an attempt to genetically distinguish Sm(R) strains from streptomycin-sensitive (Sm(S)) strains isolated in Michigan. Only 1 nucleotide difference within the total 2,660 bp sequenced from each strain was observed in 2 of 29 strains; multiple sequence differences were observed between the Michigan strains and E. amylovora control strains isolated in the western United States or from Rubus spp. Alterations in virulence observable using an immature pear fruit assay were detected in three of eight Sm(R) strains examined. Our current genetic data indicate that only two Sm(R) strain genotypes (strains containing pEA29::Tn5393 with Tn5393 inserted at either nucleotide position 1,515 or 17,527 on the plasmid) are responsible for the dissemination of Tn5393-encoded streptomycin resistance in Michigan, and that the Sm(R) and Sm(S) strains in Michigan compose a homogenous group.

Establishing alighting preferences and species transmission differences for Pea seed-borne mosaic virus aphid vectors.

PubMed

Congdon, B S; Coutts, B A; Renton, M; Flematti, G R; Jones, R A C

2017-09-15

Pea seed-borne mosaic virus (PSbMV) infection causes a serious disease of field pea (Pisum sativum) crops worldwide. The PSbMV transmission efficiencies of five aphid species previously found landing in south-west Australian pea crops in which PSbMV was spreading were studied. With plants of susceptible pea cv. Kaspa, the transmission efficiencies of Aphis craccivora, Myzus persicae, Acyrthosiphon kondoi and Rhopalosiphum padi were 27%, 26%, 6% and 3%, respectively. Lipaphis erysimi did not transmit PSbMV in these experiments. The transmission efficiencies found for M. persicae and A. craccivora resembled earlier findings, but PSbMV vector transmission efficiency data were unavailable for A. kondoi, R. padi and L. erysimi. With plants of partially PSbMV resistant pea cv. PBA Twilight, transmission efficiencies of M. persicae, A. craccivora and R. padi were 16%, 12% and 1%, respectively, reflecting putative partial resistance to aphid inoculation. To examine aphid alighting preferences over time, free-choice assays were conducted with two aphid species representing efficient (M. persicae) and inefficient (R. padi) vector species. For this, alatae were set free on multiple occasions (10-15 repetitions each) amongst PSbMV-infected and mock-inoculated pea or faba bean (Vicia faba) plants. Following release, non-viruliferous R. padi alatae exhibited a general preference for PSbMV-infected pea and faba bean plants after 30min-4h, but preferred mock-inoculated plants after 24h. In contrast, non-viruliferous M. persicae alatae alighted on mock-inoculated pea plants preferentially for up to 48h following their release. With faba bean, M. persicae preferred infected plants at the front of assay cages, but mock-inoculated ones their backs, apparently due to increased levels of natural light there. When preliminary analyses were performed to detect PSbMV-induced changes in the volatile organic compound profiles of pea and faba bean plants, higher numbers of volatiles representing a range of compound groups (such as aldehydes, ketones and esters) were found in the headspaces of PSbMV-infected than of mock-inoculated pea or faba bean plants. This indicates PSbMV induces physiological changes in these hosts which manifest as altered volatile emissions. These alterations could be responsible for the differences in alighting preferences. Information from this study enhances understanding of virus-vector relationships in the PSbMV-pea and faba bean pathosystems. Copyright © 2017 Elsevier B.V. All rights reserved.

Oxidative stress in patients with endodontic pathologies

PubMed Central

Vengerfeldt, Veiko; Mändar, Reet; Saag, Mare; Piir, Anneli; Kullisaar, Tiiu

2017-01-01

Background Apical periodontitis (AP) is an inflammatory disease affecting periradicular tissues. It is a widespread condition but its etiopathogenetic mechanisms have not been completely elucidated and the current treatment options are not always successful. Purpose To compare oxidative stress (OxS) levels in the saliva and the endodontium (root canal [RC] contents) in patients with different endodontic pathologies and in endodontically healthy subjects. Patients and methods The study group of this comparison study included 22 subjects with primary chronic apical periodontitis (pCAP), 26 with posttreatment or secondary chronic apical periodontitis (sCAP), eight with acute periapical abscess, 13 with irreversible pulpitis, and 17 healthy controls. Resting saliva samples were collected before clinical treatment. Pulp samples (remnants of the pulp, tooth tissue, and/or previous root filling material) were collected under strict aseptic conditions using the Hedström file. The samples were frozen to −80°C until analysis. OxS markers (myeloperoxidase [MPO], oxidative stress index [OSI], 8-isoprostanes [8-EPI]) were detected in the saliva and the endodontium. Results The highest MPO and 8-EPI levels were seen in pCAP and pulpitis, while the highest levels of OSI were seen in pCAP and abscess patients, as well as the saliva of sCAP patients. Controls showed the lowest OxS levels in both RC contents and saliva. Significant positive correlations between OxS markers, periapical index, and pain were revealed. Patients with pain had significantly higher OxS levels in both the endodontium (MPO median 27.9 vs 72.6 ng/mg protein, p=0.004; OSI 6.0 vs 10.4, p<0.001; 8-EPI 50.0 vs 75.0 pg/mL, p<0.001) and saliva (MPO 34.2 vs 117.5 ng/mg protein, p<0.001; 8-EPI 50.0 vs 112.8 pg/mL, p<0.001) compared to pain-free subjects. Conclusion OxS is an important pathomechanism in endodontic pathologies that is evident at both the local (RC contents) and systemic (saliva) level. OxS is significantly associated with dental pain and bone destruction. PMID:28894386

Oxidative stress in patients with endodontic pathologies.

PubMed

Vengerfeldt, Veiko; Mändar, Reet; Saag, Mare; Piir, Anneli; Kullisaar, Tiiu

2017-01-01

Apical periodontitis (AP) is an inflammatory disease affecting periradicular tissues. It is a widespread condition but its etiopathogenetic mechanisms have not been completely elucidated and the current treatment options are not always successful. To compare oxidative stress (OxS) levels in the saliva and the endodontium (root canal [RC] contents) in patients with different endodontic pathologies and in endodontically healthy subjects. The study group of this comparison study included 22 subjects with primary chronic apical periodontitis (pCAP), 26 with posttreatment or secondary chronic apical periodontitis (sCAP), eight with acute periapical abscess, 13 with irreversible pulpitis, and 17 healthy controls. Resting saliva samples were collected before clinical treatment. Pulp samples (remnants of the pulp, tooth tissue, and/or previous root filling material) were collected under strict aseptic conditions using the Hedström file. The samples were frozen to -80°C until analysis. OxS markers (myeloperoxidase [MPO], oxidative stress index [OSI], 8-isoprostanes [8-EPI]) were detected in the saliva and the endodontium. The highest MPO and 8-EPI levels were seen in pCAP and pulpitis, while the highest levels of OSI were seen in pCAP and abscess patients, as well as the saliva of sCAP patients. Controls showed the lowest OxS levels in both RC contents and saliva. Significant positive correlations between OxS markers, periapical index, and pain were revealed. Patients with pain had significantly higher OxS levels in both the endodontium (MPO median 27.9 vs 72.6 ng/mg protein, p =0.004; OSI 6.0 vs 10.4, p <0.001; 8-EPI 50.0 vs 75.0 pg/mL, p <0.001) and saliva (MPO 34.2 vs 117.5 ng/mg protein, p <0.001; 8-EPI 50.0 vs 112.8 pg/mL, p <0.001) compared to pain-free subjects. OxS is an important pathomechanism in endodontic pathologies that is evident at both the local (RC contents) and systemic (saliva) level. OxS is significantly associated with dental pain and bone destruction.

Phytotoxicity of glyphosate in the germination of Pisum sativum and its effect on germinated seedlings

PubMed Central

2017-01-01

The present study evaluated the effects of glyphosate on Pisum sativum germination as well as its effect on the physiology and biochemistry of germinated seedlings. Different physico-chemical biomarkers, viz., chlorophyll, root and shoot length, total protein and soluble sugar, along with sodium and potassium concentration, were investigated in germinated seedlings at different glyphosate concentrations. This study reports the influence of different concentrations of glyphosate on pea seeds and seedlings. Physicochemical biomarkers were significantly changed by glyphosate exposure after 15 days. The germination of seedlings under control conditions (0 mg/L) was 100% after 3 days of treatment but at 3 and 4 mg/L glyphosate, germination was reduced to 55 and 40%, respectively. Physiological parameters like root and shoot length decreased monotonically with increasing glyphosate concentration, at 14 days of observation. Average root and shoot length (n=30 in three replicates) were reduced to 14.7 and 17.6%, respectively, at 4 mg/L glyphosate. Leaf chlorophyll content also decreased, with a similar trend to root and shoot length, but the protein content initially decreased and then increased with an increase in glyphosate concentration to 3 mg/L. The study suggests that glyphosate reduces the soluble sugar content significantly, by 21.6% (v/v). But internal sodium and potassium tissue concentrations were significantly altered by glyphosate exposure with increasing concentrations of glyphosate. Biochemical and physiological analysis also supports the inhibitory effect of glyphosate on seed germination and biochemical effects on seedlings. PMID:28728354

Growth parameters of vegetable pigeon pea cultivars

USDA-ARS?s Scientific Manuscript database

Pigeon pea is an important crop in the dry regions of eastern Kenya, due to its drought tolerance and high protein content; however, farmer’s yield is limiting. Ojwang et al. (HortTech Vol 26 (1), 2016) evaluated twelve pigeon pea cultivars for flowering, plant height, branches, pod length and yield...

7 CFR 201.56-6 - Legume or pea family, Fabaceae (Leguminosae).

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 3 2011-01-01 2011-01-01 false Legume or pea family, Fabaceae (Leguminosae). 201.56-6 Section 201.56-6 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL...-6 Legume or pea family, Fabaceae (Leguminosae). Kinds of seed: Alfalfa, alyceclover, asparagusbean...

7 CFR 201.56-6 - Legume or pea family, Fabaceae (Leguminosae).

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 3 2010-01-01 2010-01-01 false Legume or pea family, Fabaceae (Leguminosae). 201.56-6 Section 201.56-6 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL...-6 Legume or pea family, Fabaceae (Leguminosae). Kinds of seed: Alfalfa, alyceclover, asparagusbean...

75 FR 53581 - Spiromesifen; Pesticide Tolerances

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-01

... regulation establishes tolerances for residues of spiromesifen in or on leaf petioles subgroup 4B, dry pea... equivalents, in or on pea, dry, seed at 0.15 parts per million (ppm); spearmint, tops at 25 ppm; and... for tolerances levels different from those proposed in the petitions for dry pea seed, spearmint tops...

The Pisum Genus: Getting out of Pea Soup!

USDA-ARS?s Scientific Manuscript database

Pea (Pisum sativum L.) has long been a model for plant genetics and is a widely grown pulse crop producing protein-rich seeds in a sustainable manner. However, many questions remain open about (sub)species relationships in the Pisumgenus. The ongoing pea genome sequencing project and the recent geno...

Saponin content and trypsin inhibitor activity in processed and cooked pigeon pea cultivars.

PubMed

Duhan, A; Khetarpaul, N; Bishnoi, S

2001-01-01

Four high-yielding varieties of pigeon pea namely UPAS-120, Manak, JCPL-151. ICPL-87 had considerable amounts of antinutrients i.e. saponins and trypsin inhibitors. Saponin content of these unprocessed cultivars ranged from 2164 to 3494 mg/100 g. There were significant varietal variations in trypsin inhibitor activity (1007-1082 TIU/g) of these pigeon pea cultivars. Some simple, inexpensive and easy-to-use domestic processing and cooking methods, namely, soaking (6, 12, 18 h), soaking (12 h)-dehulling, ordinary cooking, pressure cooking and germination (24, 36, 48 h) were found to be quite effective in lowering the level of saponins and trypsin inhibitors in all the pigeon pea cultivars. Pressure cooking of soaked and dehulled seeds lowered the content of saponins to a maximum extent (28 to 38%) followed by ordinary cooking of soaked and dehulled seeds (28 to 35%), soaked dehulled raw seeds (22 to 27%) and 48 h germinated seeds (15 to 19%). Loss of TIA was marginal due to soaking but ordinary as well as pressure cooking of unsoaked and soaked-dehulled pigeon pea seeds reduced the TIA drastically. Pressure cooking of pigeon pea seeds completely destroyed the TIA while it was reduced to the extent of 86-88% against the control in 48 h pigeon pea sprouts.

EDTA a novel inducer of pisatin, a phytoalexin indicator of the non-host resistance in peas.

PubMed

Hadwiger, Lee A; Tanaka, Kiwamu

2014-12-23

Pea pod endocarp suppresses the growth of an inappropriate fungus or non-pathogen by generating a "non-host resistance response" that completely suppresses growth of the challenging fungus within 6 h. Most of the components of this resistance response including pisatin production can be elicited by an extensive number of both biotic and abiotic inducers. Thus this phytoalexin serves as an indicator to be used in evaluating the chemical properties of inducers that can initiate the resistance response. Many of the pisatin inducers are reported to interact with DNA and potentially cause DNA damage. Here we propose that EDTA (ethylenediaminetetraacetic acid) is an elicitor to evoke non-host resistance in plants. EDTA is manufactured as a chelating agent, however at low concentration it is a strong elicitor, inducing the phytoalexin pisatin, cellular DNA damage and defense-responsive genes. It is capable of activating complete resistance in peas against a pea pathogen. Since there is also an accompanying fragmentation of pea DNA and alteration in the size of pea nuclei, the potential biochemical insult as a metal chelator may not be its primary action. The potential effects of EDTA on the structure of DNA within pea chromatin may assist the transcription of plant defense genes.

Conformational equilibrium and hydrogen bonding in liquid 2-phenylethylamine explored by Raman spectroscopy and theoretical calculations.

PubMed

Xie, Min; Qi, Yajing; Hu, Yongjun

2011-04-14

2-Phenylethylamine (PEA) is the simplest aromatic amine neurotransmitter, as well as one of the most important. In this work, the conformational equilibrium and hydrogen bonding in liquid PEA were studied by means of Raman spectroscopy and theoretical calculations (DFT/MP2). By changing the orientation of the ethyl and the NH(2) group, nine possible conformers of PEA were found, including four degenerate conformers. Comparison of the experimental Raman spectra of liquid PEA and the calculated Raman spectra of the five typical conformers in selected regions (550-800 and 1250-1500 cm(-1)) revealed that the five conformers can coexist in conformational equilibrium in the liquid. The NH(2) stretching mode of the liquid is red-shifted by ca. 30 cm(-1) relative to that of an isolated PEA molecule (measured previously), implying that intermolecular N-H···N hydrogen bonds play an important role in liquid PEA. The relative intensity of the Raman band at 762 cm(-1) was found to increase with increasing temperature, indicating that the anti conformer might be favorable in liquid PEA at room temperature. The blue shift of the band for the bonded N-H stretch with increasing temperature also provides evidence of the existence of intermolecular N-H···N hydrogen bonds.

The enigma of conditioned taste aversion learning: stimulus properties of 2-phenylethylamine derivatives.

PubMed

Greenshaw, A J; Turrkish, S; Davis, B A

2002-01-01

The functional aversive stimulus properties of several IP doses of (+/-)-amphetamine (1.25-10 mg.kg-1), 2-phenylethylamine (PEA, 2.5-10 mg.kg-1, following inhibition of monoamine oxidase with pargyline 50 mg.kg-1) and phenylethanolamine (6.25-50 mg.kg-1) were measured with the conditioned taste aversion (CTA) paradigm. A two-bottle choice procedure was used, water vs. 0.1 % saccharin with one conditioning trial and three retention trials. (+/-)-Amphetamine and phenylethanolamine induced a significant conditioned taste aversion but PEA did not. (+/-)-Amphetamine and PEA increased spontaneous locomotor activity but phenylethanolamine had no effects on this measure. Measurement of whole brain levels of these drugs revealed that the peak brain elevation of PEA occurred at approximately 10 min whereas the peak elevations of (+/-)-amphetamine and phenylethanolamine occurred at approximately 20 min. The present failure of PEA to elicit conditioned taste aversion learning is consistent with previous reports for this compound. The differential functional aversive stimulus effects of these three compounds are surprising since they exhibit similar discriminative stimulus properties and both (+/-)-amphetamine and PEA are self-administered by laboratory animals. The present data suggest that time to maximal brain concentrations following peripheral injection may be a determinant of the aversive stimulus properties of PEA derivatives.

Effect of hyperoxia on uptake and metabolism of 5-hydroxytryptamine and β-phenylethylamine in rat lung: a sex difference

PubMed Central

Ben-Harari, R.R.; Lanir, A.; Youdim, M.B.H.

1981-01-01

1 The uptake of 5-hydroxytryptamine (5—HT) and β-phenylethylamine (PEA) and their deamination by monoamine oxidase (MAO) were studied in perfused lung from male and female rats exposed to 100% O2 at 1 ATA for up to 60 h. 2 The uptake and metabolism of 5-HT in lungs from both male and female rats was not changed by exposure to O2. 3 The uptake and metabolism of PEA by lungs from male rats was unchanged. Uptake of PEA by lungs from female rats was inhibited 20% and 62% after 37 h and 50 h exposure respectively. 4 MAO activity, both in vitro and in perfused lung, was increased towards PEA after 35 h of hyperoxia. 5 Metabolism of PEA in perfused lung, measured over 30 min, was inhibited 52% after 50 h of O2 hyperoxia. 6 These results show that exposure to high concentrations of O2 damages lung, resulting in inhibition of uptake of PEA and consequently in inhibition of metabolism of PEA. 7 These results also indicate that, in lung from female rats, MAO-type B is more susceptible to changes in O2 tension than MAO type A. PMID:7236995