Pest management through Bacillus thuringiensis (Bt) in a tea-silkworm ecosystem: status and potential prospects.

PubMed

Dashora, Kavya; Roy, Somnath; Nagpal, Akanksha; Roy, Sudipta Mukhopadhyay; Flood, Julie; Prasad, Anjali Km; Khetarpal, Ravinder; Neave, Suzanne; Muraleedharan, N

2017-03-01

Bacillus thuringiensis (Bt) is a soil bacterium that forms spores containing crystals comprising one or more Cry or Cyt proteins having potential and specific insecticidal activity. Different strains of Bt produce different types of toxins, affecting a narrow taxonomic group of insects. Therefore, it is used in non-chemical pest management, including inherent pest resistance through GM crops. The specificity of action of Bt toxins reduces the concern of adverse effects on non-target species, a concern which remains with chemical insecticides as well. To make use of Bt more sustainable, new strains expressing novel toxins are actively being sought globally. Since Bt is successfully used against many pests including the lepidopteran pests in different crop groups, the insecticidal activity against Samia cynthia (Drury) (Eri silkworm) and Antheraea assamensis Helfer (Muga silkworm) becomes a concern in the state of Assam in India which is a predominantly tea- and silk-producing zone. Though Bt can be used as an effective non-chemical approach for pest management for tea pests in the same geographical region, yet, it may potentially affect the silk industry which depends on silkworm. There is a need to identify the potentially lethal impact (through evaluating their mortality potential) of local Bt strains on key silkworm species in North Eastern India. This will allow the use of existing Bt for which the silkworms have natural resistance. Through this review, the authors aim to highlight recent progress in the use of Bt and its insecticidal toxins in tea pest control and the potential sensitivity for tea- and silk-producing zone of Assam in India.

Interactions between fibroin and sericin proteins from Antheraea pernyi and Bombyx mori silk fibers.

PubMed

Du, Shan; Zhang, Jin; Zhou, Wei T; Li, Quan X; Greene, George W; Zhu, Hai J; Li, Jing L; Wang, Xun G

2016-09-15

Silkworm silk fibers are core-shell composites of fibroin and sericin proteins. Studying the interactions between fibroin and sericin is essential for understanding the properties of these composites. It is observed that compared to the domestic silk cocoon Bombyx mori (B. mori), the adhesion between fibroin and sericin from the wild silk cocoon, Antheraea pernyi (A. pernyi), is significantly stronger with a higher degree of heterogeneity. The adsorption of A. pernyi sericin on its fibroin is almost twice the value for B. mori sericin on fibroin, both showing a monolayer Langmuir adsorption. (1)H NMR and FTIR studies demonstrate on a molecular level the stronger interactions and the more intensive complex formation between A. pernyi fibroin and sericin, facilitated by the hydrogen bonding between glycine and serine. The findings of this study may help the design of composites with superior interfacial adhesion between different components. Copyright © 2016 Elsevier Inc. All rights reserved.

Comparative genomics of parasitic silkworm microsporidia reveal an association between genome expansion and host adaptation

PubMed Central

2013-01-01

Background Microsporidian Nosema bombycis has received much attention because the pébrine disease of domesticated silkworms results in great economic losses in the silkworm industry. So far, no effective treatment could be found for pébrine. Compared to other known Nosema parasites, N. bombycis can unusually parasitize a broad range of hosts. To gain some insights into the underlying genetic mechanism of pathological ability and host range expansion in this parasite, a comparative genomic approach is conducted. The genome of two Nosema parasites, N. bombycis and N. antheraeae (an obligatory parasite to undomesticated silkworms Antheraea pernyi), were sequenced and compared with their distantly related species, N. ceranae (an obligatory parasite to honey bees). Results Our comparative genomics analysis show that the N. bombycis genome has greatly expanded due to the following three molecular mechanisms: 1) the proliferation of host-derived transposable elements, 2) the acquisition of many horizontally transferred genes from bacteria, and 3) the production of abundnant gene duplications. To our knowledge, duplicated genes derived not only from small-scale events (e.g., tandem duplications) but also from large-scale events (e.g., segmental duplications) have never been seen so abundant in any reported microsporidia genomes. Our relative dating analysis further indicated that these duplication events have arisen recently over very short evolutionary time. Furthermore, several duplicated genes involving in the cytotoxic metabolic pathway were found to undergo positive selection, suggestive of the role of duplicated genes on the adaptive evolution of pathogenic ability. Conclusions Genome expansion is rarely considered as the evolutionary outcome acting on those highly reduced and compact parasitic microsporidian genomes. This study, for the first time, demonstrates that the parasitic genomes can expand, instead of shrink, through several common molecular mechanisms

Nucleopolyhedroviruses (NPV) induce the expression of small heat shock protein 25.4 in Antheraea pernyi.

PubMed

Zhang, Congfen; Zhu, Baojian; Dai, Li Shang; Liu, Chaoliang; Luo, Xuegang

2016-10-15

Nucleopolyhedroviruses (NPVs) is one group of Baculoviruses. The infection of NPV in silkworm is often lethal. To investigate the effective measures to stop the infection of NPV, we cloned cDNA encoding small heat shock protein 25.4 in Antheraea pernyi (Ap-HSP25.4). The translated amino acid sequence consisted of 223 residues with a calculated molecular mass of 25.4kDa and an isoelectronic point (pI) of 4.93. Quantitative real-time PCR was used to investigate the expression patterns and distribution profiles of Ap-sHSP25.4 before and after challenged with NPV. We found that the inhibitors of eicosanoid synthesis could suppress the transcription of Ap-sHSP25.4 in the fat body in a dose dependent manner. And arachidonic acid induced the expression of Ap-sHSP25.4. Thus, we concluded that sHSPs may be promising candidates to boost insect immunity in practice. Copyright © 2016 Elsevier B.V. All rights reserved.

Strain Rate and Anisotropic Microstructure Dependent Mechanical Behaviors of Silkworm Cocoon Shells

PubMed Central

Xu, Jun; Zhang, Wen; Gao, Xiang; Meng, Wanlin; Guan, Juan

2016-01-01

Silkworm cocoons are multi-layered composite structures comprised of high strength silk fiber and sericin, and their mechanical properties have been naturally selected to protect pupas during metamorphosis from various types of external attacks. The present study attempts to gain a comprehensive understanding of the mechanical properties of cocoon shell materials from wild silkworm species Antheraea pernyi under dynamic loading rates. Five dynamic strain rates from 0.00625 s-1 to 12.5 s-1 are tested to show the strain rate sensitivity of the cocoon shell material. In the meantime, the anisotropy of the cocoon shell is considered and the cocoon shell specimens are cut along 0°, 45° and 90° orientation to the short axis of cocoons. Typical mechanical properties including Young’s modulus, yield strength, ultimate strength and ultimate strain are extracted and analyzed from the stress-strain curves. Furthermore, the fracture morphologies of the cocoon shell specimens are observed under scanning electron microscopy to help understand the relationship between the mechanical properties and the microstructures of the cocoon material. A discussion on the dynamic strain rate effect on the mechanical properties of cocoon shell material is followed by fitting our experimental results to two previous models, and the effect could be well explained. We also compare natural and dried cocoon materials for the dynamic strain rate effect and interestingly the dried cocoon shells show better overall mechanical properties. This study provides a different perspective on the mechanical properties of cocoon material as a composite material, and provides some insight for bio-inspired engineering materials. PMID:26939063

Characterization and Expression Analysis of Receptor for Activated C Kinase from Silk-producing Insect Antheraea pernyi.

PubMed

Zhu, Bao-Jian; Yu, Hao; Tian, Sen; Dai, Li-Shang; Sun, Yu; Liu, Chao-Liang

2016-01-01

The receptor for activated C kinase (RACK) is an important scaffold protein with regulatory functions in cells. However, its role in the immune response of Antheraea pernyi to pathogen challenge remains unclear. To investigate the biological functions of RACK in the wild silkworm A. pernyi, cloning was performed and the expression patterns of the RACK gene were analyzed. Sequence analysis revealed that the RACK gene was 1120 bp containing a 960-bp open reading frame. The deduced RACK protein sequence reveals the higher identity with its homologs from other insects. SDS-PAGE and western blot analysis demonstrated successful expression of a 36-kDa recombinant RACK protein in Escherichia coli. The titer of a rabbit-raised antibody against recombinant RACK protein was about 1: 20000, determined by ELISA. Real-time PCR analysis showed that RACK expression was higher in fat bodies than in other examined A. pernyi tissues. The expression of RACK mRNA in fat bodies of fifth larvae of A. pernyi was obviously induced after nucleopolyhedrovirus, E. coli or Beauveria bassiana challenge. However, the expression patterns of RACK were different in response to these pathogens. Our data suggest that RACK may play a role in the innate immune responses of A. pernyi.

Comparative transcriptomic analysis of silkwormBmovo-1 and wild type silkworm ovary

PubMed Central

Xue, Renyu; Hu, Xiaolong; Zhu, Liyuan; Cao, Guangli; Huang, Moli; Xue, Gaoxu; Song, Zuowei; Lu, Jiayu; Chen, Xueying; Gong, Chengliang

2015-01-01

The detailed molecular mechanism of Bmovo-1 regulation of ovary size is unclear. To uncover the mechanism of Bmovo-1 regulation of ovarian development and oogenesis using RNA-Seq, we compared the transcriptomes of wild type (WT) and Bmovo-1-overexpressing silkworm (silkworm+Bmovo-1) ovaries. Using a pair-end Illumina Solexa sequencing strategy, 5,296,942 total reads were obtained from silkworm+Bmovo-1 ovaries and 6,306,078 from WT ovaries. The average read length was about 100 bp. Clean read ratios were 98.79% for silkworm+Bmovo-1 and 98.87% for WT silkworm ovaries. Comparative transcriptome analysis showed 123 upregulated and 111 downregulated genes in silkworm+Bmovo-1 ovaries. These differentially expressed genes were enriched in the extracellular and extracellular spaces and involved in metabolism, genetic information processing, environmental information processing, cellular processes and organismal systems. Bmovo-1 overexpression in silkworm ovaries might promote anabolism for ovarian development and oogenesis and oocyte proliferation and transport of nutrients to ovaries by altering nutrient partitioning, which would support ovary development. Excessive consumption of nutrients for ovary development alters nutrient partitioning and deters silk protein synthesis. PMID:26643037

Role of tropomyosin in silkworm allergy.

PubMed

Jeong, Kyoung Yong; Han, In-Soo; Lee, June Yong; Park, Kyung Hee; Lee, Jae-Hyun; Park, Jung-Won

2017-05-01

Silkworm pupae are widely consumed in Asian countries and allergic reactions following consumption have been described. However, false‑positive responses in skin prick allergy tests or non‑specific immunoglobulin E (IgE) responses to total extract of silkworm pupa make diagnosis difficult. Although improved allergy diagnosis is required, molecular characterization of silkworm allergens has not been performed to date, except for Bomb m 1, an arginine kinase. This study aimed to evaluate the allergenicity of tropomyosin, a well‑established invertebrate pan‑allergen, from silkworm pupa. The silkworm tropomyosin gene was cloned by reverse transcription and polymerase chain reaction, and the protein was overexpressed in Escherichia coli and purified by affinity chromatography using Nickel‑resin. IgE reactivity of the recombinant protein was examined by ELISA and competitive inhibition analyses. Silkworm pupa tropomyosin shared 73.5‑92.3% amino acid sequence identity with previously identified allergenic tropomyosins. Sera from eight of 15 patients with silkworm allergy (53.3%) exhibited binding of IgE to the recombinant protein. However, recombinant protein was able to inhibit less than 10% of IgE reactivity to silkworm pupa extract. Of the eight sera tested, six that specifically reacted with silkworm tropomyosin also demonstrated IgE reactivity to shrimp and crab. In the present study, specific IgE to silkworm tropomyosin was detected in patients with silkworm allergy, suggesting that it may be useful in diagnosis of allergy to silkworm pupa.

Silkworms transformed with chimeric silkworm/spider silk genes spin composite silk fibers with improved mechanical properties

USDA-ARS?s Scientific Manuscript database

The development of a spider silk manufacturing process is of great interest. piggyBac vectors were used to create transgenic silkworms encoding chimeric silkworm/spider silk proteins. The silk fibers produced by these animals were composite materials that included chimeric silkworm/spider silk prote...

Comparative methylomics between domesticated and wild silkworms implies possible epigenetic influences on silkworm domestication

PubMed Central

2013-01-01

Background In contrast to wild species, which have typically evolved phenotypes over long periods of natural selection, domesticates rapidly gained human-preferred agronomic traits in a relatively short-time frame via artificial selection. Under domesticated conditions, many traits can be observed that cannot only be due to environmental alteration. In the case of silkworms, aside from genetic divergence, whether epigenetic divergence played a role in domestication is an unanswered question. The silkworm is still an enigma in that it has two DNA methyltransferases (DNMT1 and DNMT2) but their functionality is unknown. Even in particular the functionality of the widely distributed DNMT1 remains unknown in insects in general. Results By embryonic RNA interference, we reveal that knockdown of silkworm Dnmt1 caused decreased hatchability, providing the first direct experimental evidence of functional significance of insect Dnmt1. In the light of this fact and those that DNA methylation is correlated with gene expression in silkworms and some agronomic traits in domesticated organisms are not stable, we comprehensively compare silk gland methylomes of 3 domesticated (Bombyx mori) and 4 wild (Bombyx mandarina) silkworms to identify differentially methylated genes between the two. We observed 2-fold more differentiated methylated cytosinces (mCs) in domesticated silkworms as compared to their wild counterparts, suggesting a trend of increasing DNA methylation during domestication. Further study of more domesticated and wild silkworms narrowed down the domesticates’ epimutations, and we were able to identify a number of differential genes. One such gene showing demethyaltion in domesticates correspondently displays lower gene expression, and more interestingly, has experienced selective sweep. A methylation-increased gene seems to result in higher expression in domesticates and the function of its Drosophila homolog was previously found to be essential for cell volume

Phylogeny and evolutionary history of the silkworm.

PubMed

Sun, Wei; Yu, Hongsong; Shen, Yihong; Banno, Yutaka; Xiang, Zhonghuai; Zhang, Ze

2012-06-01

The silkworm, Bombyx mori, played an important role in the old Silk Road that connected ancient Asia and Europe. However, to date, there have been few studies of the origins and domestication of this species using molecular methods. In this study, DNA sequences of mitochondrial and nuclear loci were used to infer the phylogeny and evolutionary history of the domesticated silkworm and its relatives. All of the phylogenetic analyses indicated a close relationship between the domesticated silkworm and the Chinese wild silkworm. Domestication was estimated to have occurred about 4100 years ago (ya), and the radiation of the different geographic strains of B. mori about 2000 ya. The Chinese wild silkworm and the Japanese wild silkworm split about 23600 ya. These estimates are in good agreement with the fossil evidence and historical records. In addition, we show that the domesticated silkworm experienced a population expansion around 1000 ya. The divergence times and the population dynamics of silkworms presented in this study will be useful for studies of lepidopteran phylogenetics, in the genetic analysis of domestic animals, and for understanding the spread of human civilizations.

Spectral imaging analysis for silkworm gender classification

NASA Astrophysics Data System (ADS)

Sumriddetchkajorn, Sarun; Kamtongdee, Chakkrit; Sa-Ngiamsak, Chiranut

2013-05-01

We examine the effect of different wavelength spectra in the performance of our optical penetration-based silkworm pupa sex identification system. With available low-cost light emitting diodes (LEDs), each emitting different wavelength spectra at 468 nm, 565 nm, 639 nm, 940 nm, and broad white light, we find that the body of the silkworm pupa can block blue and near infrared light while allowing green and red light pass through. In particular, the red light can clearly highlight an important organ called "chitin gland" of the female, leading to high accuracy of silkworm gender identification. In our experiment with 120 silkworm pupae, measured high average 92.8% and lower average 87.5% accuracies in identifying silkworm gender are obtained under red and white light LEDs, respectively.

Overexpression of host plant urease in transgenic silkworms.

PubMed

Jiang, Liang; Huang, Chunlin; Sun, Qiang; Guo, Huizhen; Peng, Zhengwen; Dang, Yinghui; Liu, Weiqiang; Xing, Dongxu; Xu, Guowen; Zhao, Ping; Xia, Qingyou

2015-06-01

Bombyx mori and mulberry constitute a model of insect-host plant interactions. Urease hydrolyzes urea to ammonia and is important for the nitrogen metabolism of silkworms because ammonia is assimilated into silk protein. Silkworms do not synthesize urease and acquire it from mulberry leaves. We synthesized the artificial DNA sequence ureas using the codon bias of B. mori to encode the signal peptide and mulberry urease protein. A transgenic vector that overexpresses ure-as under control of the silkworm midgut-specific P2 promoter was constructed. Transgenic silkworms were created via embryo microinjection. RT-PCR results showed that urease was expressed during the larval stage and qPCR revealed the expression only in the midgut of transgenic lines. Urea concentration in the midgut and hemolymph of transgenic silkworms was significantly lower than in a nontransgenic line when silkworms were fed an artificial diet. Analysis of the daily body weight and food conversion efficiency of the fourth and fifth instar larvae and economic characteristics indicated no differences between transgenic silkworms and the nontransgenic line. These results suggested that overexpression of host plant urease promoted nitrogen metabolism in silkworms.

Silkworm: A Promising Model Organism in Life Science.

PubMed

Meng, Xu; Zhu, Feifei; Chen, Keping

2017-09-01

As an important economic insect, silkworm Bombyx mori (L.) (Lepidoptera: Bombycidae) has numerous advantages in life science, such as low breeding cost, large progeny size, short generation time, and clear genetic background. Additionally, there are rich genetic resources associated with silkworms. The completion of the silkworm genome has further accelerated it to be a modern model organism in life science. Genomic studies showed that some silkworm genes are highly homologous to certain genes related to human hereditary disease and, therefore, are a candidate model for studying human disease. In this article, we provided a review of silkworm as an important model in various research areas, including human disease, screening of antimicrobial agents, environmental safety monitoring, and antitumor studies. In addition, the application potentiality of silkworm model in life sciences was discussed. © The Author 2017. Published by Oxford University Press on behalf of Entomological Society of America.

Survey and Analysis of Microsatellites in the Silkworm, Bombyx mori

PubMed Central

Prasad, M. Dharma; Muthulakshmi, M.; Madhu, M.; Archak, Sunil; Mita, K.; Nagaraju, J.

2005-01-01

We studied microsatellite frequency and distribution in 21.76-Mb random genomic sequences, 0.67-Mb BAC sequences from the Z chromosome, and 6.3-Mb EST sequences of Bombyx mori. We mined microsatellites of ≥15 bases of mononucleotide repeats and ≥5 repeat units of other classes of repeats. We estimated that microsatellites account for 0.31% of the genome of B. mori. Microsatellite tracts of A, AT, and ATT were the most abundant whereas their number drastically decreased as the length of the repeat motif increased. In general, tri- and hexanucleotide repeats were overrepresented in the transcribed sequences except TAA, GTA, and TGA, which were in excess in genomic sequences. The Z chromosome sequences contained shorter repeat types than the rest of the chromosomes in addition to a higher abundance of AT-rich repeats. Our results showed that base composition of the flanking sequence has an influence on the origin and evolution of microsatellites. Transitions/transversions were high in microsatellites of ESTs, whereas the genomic sequence had an equal number of substitutions and indels. The average heterozygosity value for 23 polymorphic microsatellite loci surveyed in 13 diverse silkmoth strains having 2–14 alleles was 0.54. Only 36 (18.2%) of 198 microsatellite loci were polymorphic between the two divergent silkworm populations and 10 (5%) loci revealed null alleles. The microsatellite map generated using these polymorphic markers resulted in 8 linkage groups. B. mori microsatellite loci were the most conserved in its immediate ancestor, B. mandarina, followed by the wild saturniid silkmoth, Antheraea assama. PMID:15371363

Demographic history and gene flow during silkworm domestication

PubMed Central

2014-01-01

Background Gene flow plays an important role in domestication history of domesticated species. However, little is known about the demographic history of domesticated silkworm involving gene flow with its wild relative. Results In this study, four model-based evolutionary scenarios to describe the demographic history of B. mori were hypothesized. Using Approximate Bayesian Computation method and DNA sequence data from 29 nuclear loci, we found that the gene flow at bottleneck model is the most likely scenario for silkworm domestication. The starting time of silkworm domestication was estimated to be approximate 7,500 years ago; the time of domestication termination was 3,984 years ago. Using coalescent simulation analysis, we also found that bi-directional gene flow occurred during silkworm domestication. Conclusions Estimates of silkworm domestication time are nearly consistent with the archeological evidence and our previous results. Importantly, we found that the bi-directional gene flow might occur during silkworm domestication. Our findings add a dimension to highlight the important role of gene flow in domestication of crops and animals. PMID:25123546

Silkworm protein: its possibility as an actuator

NASA Astrophysics Data System (ADS)

Jin, Hyoung-Joon; Myung, Seung Jun; Kim, Heung Soo; Jung, Woochul; Kim, Jaehwan

2006-03-01

The possibility of silkworm (Bombyx mori) protein as a base material of biomimetic actuator was investigated in this paper. Silkworm films were prepared from high concentrations of regenerated fibroin in aqueous solution. Films with thickness of about 100 μm were prepared for coating electrodes. The cast silk films were coated by very thin gold electrode on both sides of the film. Tensile test of cast film showed bi-modal trend, which is typical stress-strain relation of polymeric film. As the test of a possible biomimetic actuator, silkworm film actuator provides bending deformations according to the magnitude and frequency of the applied electric filed. Although the present bending deformation of silkworm film actuator is smaller than that of Electro-Active Paper actuator, it provides the possibility of biomimetic actuator.

Effects of High Magneto-Gravitational Environment on Silkworm Embryogenesis

NASA Astrophysics Data System (ADS)

Tian, Zongcheng; Li, Muwang; Qian, Airong; Xu, Huiyun; Wang, Zhe; Di, Shengmeng; Yang, Pengfei; Hu, Lifang; Ding, Chong; Zhang, Wei; Luo, Mingzhi; Han, Jing; Gao, Xiang; Huang, Yongping; Shang, Peng

2010-04-01

The objective of this research was to observe whether silkworm embryos can survive in a high magneto-gravitational environment (HMGE) and what significant phenotype changes can be produced. The hatching rate, hatching time, life span, growth velocity and cocoon weight of silkworm were measured after silkworm embryos were exposed to HMGE (0 g, 12 T; 1 g, 16 T; and 2 g, 12 T) for a period of time. Compared with the control group, 0 g exposure resulted in a lower hatching rate and a shorter life span. Statistically insignificant morphological changes had been observed for larvae growth velocity, incidence of abnormal markings and weight of cocoons. These results suggest that the effect of HMGE on silkworm embryogenesis is not lethal. Bio-effects of silkworm embryogenesis at 0 g in a HMGE were similar with those of space flight. The hatching time, life span and hatching rates of silkworm may be potential phenotype markers related to exposure in a weightless environment.

Nucleotide Diversity and Selection Signature in the Domesticated Silkworm, Bombyx mori, and Wild Silkworm, Bombyx mandarina

PubMed Central

Guo, Yi; Shen, Yi-Hong; Sun, Wei; Kishino, Hirohisa; Xiang, Zhong-Huai; Zhang, Ze

2011-01-01

To investigate the patterns of nucleotide diversity in domesticated silkworm, Bombyx mori L. (Lepidoptera: Bombycidae) and its wild relative, Chinese wild silkworm, Bombyx mandarina Moore, we sequenced nine nuclear genes. Neutrality test and coalescent simulation for these genes were performed to look at bottleneck intensity and selection signature; linkage disequilibrium (LD) within and between loci was employed to investigate allele association. As a result, B. mori lost 33–49% of nucleotide diversity relative to wild silkworm, which is similar to the loss levels found in major cultivated crops. Diversity of B. mori is significantly lower than that of B. mandarina measured as πtotal (0.01166 vs. 0.1741) or θW(0.01124 vs. 0.02206). Bottleneck intensity of domesticated silkworm is 1.5 (in terms of k = Nb/d, Nb-bottleneck population size; d-bottleneck duration) with different durations. Gene DefA showed signature of artificial selection by all analysis methods and might experience strong artificial selection in B. mori during domestication. For nine loci, both curves of LD decay rapidly within 200 bp and drop slowly when distance is > 200 bp, although that of B. mori decays slower than B. mandarina at loci investigated. However, LD could not be estimated at DefA in B. mori and at ER in both silkworms. Elevated LD observed in B. mori may be indicator of selection and demographic events. PMID:22239062

Acute oral toxicity test of chemical compounds in silkworms.

PubMed

Usui, Kimihito; Nishida, Satoshi; Sugita, Takuya; Ueki, Takuro; Matsumoto, Yasuhiko; Okumura, Hidenobu; Sekimizu, Kazuhisa

2016-02-01

This study performed an acute oral toxicity test of 59 compounds in silkworms. These compounds are listed in OECD guidelines as standard substances for a cytotoxicity test, and median lethal dose (LD(50)) werecalculated for each compound. Acute oral LD(50) values in mammals are listed in OECD guidelines and acute oral LD(50) values in silkworms were determined in this study. R(2) for the correlation between LD(50) values in mammals and LD(50) values in silkworms was 0.66. In addition, the acute oral toxicity test in silkworms was performed by two different facilities, and test results from the facilities were highly reproducible. These findings suggest that an acute oral toxicity test in silkworms is a useful way to evaluate the toxicity of compounds in mammals.

[Identification of novel therapeutically effective antibiotics using silkworm infection model].

PubMed

Hamamoto, Hiroshi; Urai, Makoto; Paudel, Atmika; Horie, Ryo; Murakami, Kazuhisa; Sekimizu, Kazuhisa

2012-01-01

Most antibiotics obtained by in vitro screening with antibacterial activity have inappropriate properties as medicines due to their toxicity and pharmacodynamics in animal bodies. Thus, evaluation of the therapeutic effects of these samples using animal models is essential in the crude stage. Mammals are not suitable for therapeutic evaluation of a large number of samples due to high costs and ethical issues. We propose the use of silkworms (Bombyx mori) as model animals for screening therapeutically effective antibiotics. Silkworms are infected by various pathogenic bacteria and are effectively treated with similar ED(50) values of clinically used antibiotics. Furthermore, the drug metabolism pathways, such as cytochrome P450 and conjugation systems, are similar between silkworms and mammals. Silkworms have many advantages compared with other infection models, such as their 1) low cost, 2) few associated ethical problems, 3) adequate body size for easily handling, and 4) easier separation of organs and hemolymph. These features of the silkworm allow for efficient screening of therapeutically effective antibiotics. In this review, we discuss the advantages of the silkworm model in the early stages of drug development and the screening results of some antibiotics using the silkworm infection model.

Silk Spinning in Silkworms and Spiders

PubMed Central

Andersson, Marlene; Johansson, Jan; Rising, Anna

2016-01-01

Spiders and silkworms spin silks that outcompete the toughness of all natural and manmade fibers. Herein, we compare and contrast the spinning of silk in silkworms and spiders, with the aim of identifying features that are important for fiber formation. Although spiders and silkworms are very distantly related, some features of spinning silk seem to be universal. Both spiders and silkworms produce large silk proteins that are highly repetitive and extremely soluble at high pH, likely due to the globular terminal domains that flank an intermediate repetitive region. The silk proteins are produced and stored at a very high concentration in glands, and then transported along a narrowing tube in which they change conformation in response primarily to a pH gradient generated by carbonic anhydrase and proton pumps, as well as to ions and shear forces. The silk proteins thereby convert from random coil and alpha helical soluble conformations to beta sheet fibers. We suggest that factors that need to be optimized for successful production of artificial silk proteins capable of forming tough fibers include protein solubility, pH sensitivity, and preservation of natively folded proteins throughout the purification and initial spinning processes. PMID:27517908

Silk Spinning in Silkworms and Spiders.

PubMed

Andersson, Marlene; Johansson, Jan; Rising, Anna

2016-08-09

Spiders and silkworms spin silks that outcompete the toughness of all natural and manmade fibers. Herein, we compare and contrast the spinning of silk in silkworms and spiders, with the aim of identifying features that are important for fiber formation. Although spiders and silkworms are very distantly related, some features of spinning silk seem to be universal. Both spiders and silkworms produce large silk proteins that are highly repetitive and extremely soluble at high pH, likely due to the globular terminal domains that flank an intermediate repetitive region. The silk proteins are produced and stored at a very high concentration in glands, and then transported along a narrowing tube in which they change conformation in response primarily to a pH gradient generated by carbonic anhydrase and proton pumps, as well as to ions and shear forces. The silk proteins thereby convert from random coil and alpha helical soluble conformations to beta sheet fibers. We suggest that factors that need to be optimized for successful production of artificial silk proteins capable of forming tough fibers include protein solubility, pH sensitivity, and preservation of natively folded proteins throughout the purification and initial spinning processes.

Fruit body formation on silkworm by Cordyceps militaris

USDA-ARS?s Scientific Manuscript database

Injection inoculation protocols for fruit body formation of Cordyceps militaris were investigated to improve the incidence of infection in the silkworm species Bombyx mori. Injection, with suspensions of C. militaris hyphal bodies into living silkworm pupae, was used to test for fruit body productio...

Feeding scenario of the silkworm Bombyx Mori, L. in the BLSS

NASA Astrophysics Data System (ADS)

Yu, XiaoHui; Liu, Hong; Tong, Ling

A simple subunit of the bioregenerative life support system (BLSS) consisting of the ground-controlled mulberry ( Morus alba L.) and the silkworms was set up on the ground. The mulberry tree could provide nutrient mulberry fruits for astronauts and its leaves as the main feedstuff for the silkworms until their third instar. Astronauts utilized curled lettuce ( Lactuca sativa L.) stem as vegetables and the silkworms over third instar could be fed on 65% of inedible leaves of the lettuce. About 71.4% of protein were detected in the silkworm larval powder; thus, 105 silkworms could satisfy the requirement of one person per day. Besides, 18 kinds of amino acids were determined in the obtained silkworm powder. Moreover, the R-criterion was suggested to estimate and optimize the animal feeding facilities. The scenario of treating the wastes is also proposed in this paper. Our results may be valuable for the establishment of a complex BLSS in the future.

Analysis of silkworm gut microflora in the Bioregenerative Life Support System

NASA Astrophysics Data System (ADS)

Liang, Xue; Liu, lh64. Hong

2012-07-01

Silkworm (Bombyx mori L) has advantages in the nutritional composition, growth characteristics and other factors, it is regarded as animal protein source for astronauts in the Bioregenerative Life Support System (BLSS).Due to the features of BLSS, silkworm breeding way is different from the conventional one (mulberry leaves throughout five instars): they were fed with mulberry and lettuce leaves during the 1st-3rd instars and 4th -5th instars, respectively. As the lettuce stem can be eaten by astronauts, the leaves not favored by humans can be insect's foodstuff. Therefore, it is necessary to investigate the gut microbial composition, the type of dominant bacteria of silkworm raised with this way and the differences from the conventional breeding method, so as to reduce the mortality rate caused by the foodstuff change and to provide more animal protein for astronauts. In this study, 16srDNA sequencing, phylogenetic analysis and denaturing gradient gel electrophoresis method were used to analyze the silkworm gut microbial flora under two breeding manners. The results show that conventional and BLSS breeding way have six dominant bacteria in common: Clostridium, Enterococcus, Bacteroides, Chryseobacterium, Parabacteroides, Paenibacillus. We also found Escherichia, Janthinobacterium, Sedimentibacter, Streptococcus, Bacillus, Arcobacter, Rothia, Polaribacter and Acinetobacter, Anaerofilum, Rummeliibacillus, Anaeroplasma, Serratia in the ground conventional and BLSS special breeding way, respectively. Changing the foodstuff of silkworm leads to the dynamic alteration of gut microbial. Dominant bacteria of the two breeding ways have diversities from each other. The ground conventional breeding way has more abundant bacteria than the BLSS one. Due to the lettuce leaves have replaced mulberry leaves at the beginning of the silkworm 4th instar, some silkworms can not survive without the bacteria that digest and absorb lettuce leaves. We suggest those dominant bacteria

Highly accurate and fast optical penetration-based silkworm gender separation system

NASA Astrophysics Data System (ADS)

Kamtongdee, Chakkrit; Sumriddetchkajorn, Sarun; Chanhorm, Sataporn

2015-07-01

Based on our research work in the last five years, this paper highlights our innovative optical sensing system that can identify and separate silkworm gender highly suitable for sericulture industry. The key idea relies on our proposed optical penetration concepts and once combined with simple image processing operations leads to high accuracy in identifying of silkworm gender. Inside the system, there are electronic and mechanical parts that assist in controlling the overall system operation, processing the optical signal, and separating the female from male silkworm pupae. With current system performance, we achieve a very highly accurate more than 95% in identifying gender of silkworm pupae with an average system operational speed of 30 silkworm pupae/minute. Three of our systems are already in operation at Thailand's Queen Sirikit Sericulture Centers.

Long-term preservation of eri and ailanthus silkworms using frozen gonads.

PubMed

Fukumori, Hisayoshi; Lee, Jung; Fujii, Tsuguru; Kajiura, Zenta; Banno, Yutaka

2017-08-01

Cryopreservation of eri and ailanthus silkworms using frozen gonads was investigated. First, we evaluated the freeze tolerance of ovary and testis in the eri silkworm, which showed high tolerance. Mating between frozen ovary-transplanted females and frozen testis-transplanted males produced 163.0 eggs, yielding 105.7 larvae per moth. In a second experiment, we tested the use of the eri silkworm as a host insect for gonad transplantation from ailanthus silkworm donors. A high success ratio for laid and hatched eggs was demonstrated for ovary transplantation (97.8 and 51.3 eggs per moth, respectively). For testis transplantation, however, the average number of hatched larvae was low (12.0). Mating between host eri females and males in which both frozen ovary and testis of the ailanthus silkworm had been transplanted produced 6.4 fertilized eggs per host moth. Our success in using cross subspecies cryopreservation between these wild silkworms could lead to the alternative use of hosts between species in other insects. Copyright © 2017 Elsevier Inc. All rights reserved.

Construction of transformed, cultured silkworm cells and transgenic silkworm using the site-specific integrase system from phage φC31.

PubMed

Yin, Yajuan; Cao, Guangli; Xue, Renyu; Gong, Chengliang

2014-10-01

The Streptomyces bacteriophage, φC31, uses a site-specific integrase enzyme to perform efficient recombination. The recombination system uses specific sequences to integrate exogenous DNA from the phage into a host. The sequences are known as the attP site in the phage and the attB site in the host. The system can be used as a genetic manipulation tool. In this study it has been applied to the transformation of cultured BmN cells and the construction of transgenic Bombyx mori individuals. A plasmid, pSK-attB/Pie1-EGFP/Zeo-PASV40, containing a cassette designed to express a egfp-zeocin fusion gene, was co-transfected into cultured BmN cells with a helper plasmid, pSK-Pie1/NLS-Int/NSL. Expression of the egfp-zeocin fusion gene was driven by an ie-1 promoter, downstream of a φC31 attB site. The helper plasmid encoded the φC31 integrase enzyme, which was flanked by two nuclear localization signals. Expression of the egfp-zeocin fusion gene could be observed in transformed cells. The two plasmids were also transferred into silkworm eggs to obtain transgenic silkworms. Successful integration of the fusion gene was indicated by the detection of green fluorescence, which was emitted by the silkworms. Nucleotide sequence analysis demonstrated that the attB site had been cut, to allow recombination between the attB and endogenous pseudo attP sites in the cultured silkworm cells and silkworm individuals.

Physicochemical Properties of Meat Batter Added with Edible Silkworm Pupae (Bombyx mori) and Transglutaminase.

PubMed

Park, Yoo-Sun; Choi, Yun-Sang; Hwang, Ko-Eun; Kim, Tae-Kyung; Lee, Cheol-Won; Shin, Dong-Min; Han, Sung Gu

2017-01-01

This study was conducted to investigate the physicochemical properties of meat batters prepared with fresh pork meat, back fat, water, and salt and formulated with three different amounts (5%, 10%, and 15%) of silkworm pupae ( Bombyx mori ) powder and transglutaminase (TG). Meat batters formulated with silkworm pupae powder showed significantly higher contents of protein and ash than control batter. Addition of silkworm pupae to batter also showed significantly lower cooking loss than the control. Moreover, meat batter containing 15% silkworm pupae showed no significant difference in redness value compared to the control. In addition, pH, viscosity, hardness, gumminess, and chewiness were improved after the addition of silkworm pupae. Furthermore, meat batter formulated with TG and silkworm pupae showed improved hardness, gumminess, chewiness and viscosity compared to control batter. Addition of 1% TG with 15% silkworm pupae to meat batter resulted in significantly higher pH, textures, and viscosity. Our data suggest that both silkworm pupae and TG can be added to meat batter to improve its physicochemical properties. Therefore, combination of silkworm pupae and TG could be a new nutritional and functional source for meat products.

Physicochemical Properties of Meat Batter Added with Edible Silkworm Pupae (Bombyx mori) and Transglutaminase

PubMed Central

Choi, Yun-Sang

2017-01-01

This study was conducted to investigate the physicochemical properties of meat batters prepared with fresh pork meat, back fat, water, and salt and formulated with three different amounts (5%, 10%, and 15%) of silkworm pupae (Bombyx mori) powder and transglutaminase (TG). Meat batters formulated with silkworm pupae powder showed significantly higher contents of protein and ash than control batter. Addition of silkworm pupae to batter also showed significantly lower cooking loss than the control. Moreover, meat batter containing 15% silkworm pupae showed no significant difference in redness value compared to the control. In addition, pH, viscosity, hardness, gumminess, and chewiness were improved after the addition of silkworm pupae. Furthermore, meat batter formulated with TG and silkworm pupae showed improved hardness, gumminess, chewiness and viscosity compared to control batter. Addition of 1% TG with 15% silkworm pupae to meat batter resulted in significantly higher pH, textures, and viscosity. Our data suggest that both silkworm pupae and TG can be added to meat batter to improve its physicochemical properties. Therefore, combination of silkworm pupae and TG could be a new nutritional and functional source for meat products. PMID:28747820

Nutrient composition and respiration characteristics of silkworms in the Bioregenerative Life Support System

NASA Astrophysics Data System (ADS)

Tong, Ling; Yu, Xiaohui; Liu, Hong

As the appropriate space animal candidate, silkworm(Bombyx Mori L.) can supply animal food for taikonauts and consume inedible parts of plants in Bioregenerative Life Support Sys-tem(BLSS). Due to the features of BLSS, the silkworm breeding method in the system differ-ent from the conventional one is feeding the silkworm in the first three developing stages with mulberry leaves and with lettuce leaves in the latter two developing stages. Therefore, it is nec-essary to investigate the biochemical components and respiration characteristics of silkworms raised with this method to supply data bases for the inclusion of silkworms in the system to conduct system experiments. The nutrient compositions of silkworm powder (SP) which are the grinded and freeze-dried silkworm on the 3rd day in the fifth developing stage containing protein, fat, vitamins, minerals and fatty acids were determined with international standard analyzing methods in this study. The results showed that SP was rich in protein and amino acids. There were twelve kinds of essential vitamins, nine kinds of minerals and twelve kinds of fatty acids in SP. In contrast, SP had much better nutrient components than snail, fish, chicken, beef and pork as animal food for crew members. Moreover, 359 kCal can be generated per 100g of SP (dry weight). The respirations of silkworm during its whole growing process under two main physiological statuses which were eating and non-eating leaves were studied. According to the results measured by the animal respiration measuring system, there were much difference among the respirations of silkworms under the two main physiological statuses. The amounts of O2 inhaled and CO2 exhaled by the silkworms when they were eating leaves were more than those under the non-eating status. Even under the same status, the respiration characteristics of silkworms in five different developing stages were also different from one an-other. The respiratory quotients of silkworms under two

Effect of feeding silkworm on growth performance and feed efficiency of snakehead (Channa striata)

NASA Astrophysics Data System (ADS)

Firmani, U.; Lono

2018-04-01

The snakehead, Chana striata is a carnivorous freshwater fish and widely distributed in Asia. High demand of this fish has been triggering many aquaculturist to culture C. stiata. Feed was the important factor for fish growth. Silkworm has high protein content, low fat and can be used as natural feed for finfish. This study investigate the silkworm feed in C. striata. The treatment of this research were A (100 % pellet); B (100 % silkworm); C (combination of 75 % pellet and 25 % silkworm); D (combination of 50 % pellet and 50 % silkworm); and E (combination of 25 % pellet and 75 % silkworm). The variables measured in this study were relatif growth, specific growth rate, feed efficiency, feed conversion ratio, and survival rate. The result show that silkworm gave the high growth performance, feed efficiency and survival rate of the snakehead (Channa striata) compared with the control.

Accumulation of 1-deoxynojirimycin in silkworm, Bombyx mori L.

PubMed

Yin, Hao; Shi, Xin-qin; Sun, Bo; Ye, Jing-jing; Duan, Zu-an; Zhou, Xiao-ling; Cui, Wei-zheng; Wu, Xiao-feng

2010-04-01

1-deoxynojirimycin (1-DNJ) contents in the silkworm, Bombyx mori, at different developmental stages and tissues were investigated by using reverse-phase high-performance liquid chromatography. The 1-DNJ contents of silkworm larvae change significantly with their developmental stages. The male larvae showed higher accumulation efficiency of 1-DNJ than the females and also a significant variation was observed among the silkworm strains. The present results show that tissue distribution of 1-DNJ was significantly higher in blood, digestive juice, and alimentary canal, but no 1-DNJ was observed in the silkgland. Moreover, 1-DNJ was not found in silkworms fed with artificial diet that does not contain mulberry leaf powder. This proves that silkworms obtain 1-DNJ from mulberry leaves; they could not synthesize 1-DNJ by themselves. The accumulation and excretion of 1-DNJ change periodically during the larval stage. There was no 1-DNJ in the newly-hatched larvae and 1-DNJ was mainly accumulated during the early and middle stages of every instar, while excreted at later stages of larval development. Further, it is possible to extract 1-DNJ from the larval feces and it is optimal to develop the 1-DNJ related products for diabetic auxiliary therapy.

Hippo pathway regulates somatic development and cell proliferation of silkworm.

PubMed

Li, Niannian; Tong, Xiaoling; Zeng, Jie; Meng, Gang; Sun, Fuze; Hu, Hai; Song, Jiangbo; Lu, Cheng; Dai, Fangyin

2018-03-01

Hippo signaling pathway (signaling pathway Hippo, hereinafter referred to as the Hippo pathway) was the earliest found in Drosophila (Schneck [1]), which can regulate the development of tissues and organs, even some components of the pathway were identified as tumor suppressor [2]. The pathway was more concerned in fruit flies and mice (Schneck [1]), but little attention has been given in silkworm, an important economic and lepidopteran model insect. In this manuscript, we identified major Hippo pathway related genes (Hippo, Salvador, Warts, Mats, Yorkie) in silkworm and named BmHpo, BmSav, BmWts, BmMats, BmYki. The domain organization of these genes was highly conserved in silkworm and other organisms suggesting that they could use similar protein-protein interactions to construct the Hippo kinase cascades. The expression profiles of these genes in silkworm during embryonic, larval, wandering, pupal and adult stages were analyzed, 14 tissues/organs of the day 3, 5th instar larvae (L5D3) as well. Experimental results showed that the expression of Hippo pathway had some influence on the development of silkworm. In order to find out the mechanism of Hippo pathway affecting silkworm development, BmHpo and BmYki were up-regulated and de-regulated in the cell line of Bombyx mori-BmN-SWU1(NS), and the changes of cell proliferation activity and cell cycle were detected. The distribution of BmYki was detected by immunofluorescence technique. This study provides insights into the genes of Hippo pathway which have a certain effect on somatic development and cell proliferation in silkworm. Copyright © 2018 Elsevier Inc. All rights reserved.

Transgenic breeding of anti-Bombyx mori L. nuclear polyhedrosis virus silkworm Bombyx mori.

PubMed

Yang, Huijuan; Fan, Wei; Wei, Hao; Zhang, Jinwei; Zhou, Zhonghua; Li, Jianying; Lin, Jianrong; Ding, Nong; Zhong, Boxiong

2008-10-01

Silkworm strains resistant to Bombyx mori L. nuclear polyhedrosis virus were obtained through transgenic experiments. piggyBac transposon with an A3 promoter were randomly inserted into the silkworm, driving the enhanced green fluorescent protein (EGFP) reporter gene into the silkworm genome. Polymerase chain reaction results verified the insertion of the extraneous EGFP gene, and fluorescence microscopy showed that the EGFP was expressed in the midgut tissue. The morbidity ratio of the nuclear polyhedrosis decreased from 90% in the original silkworm strain to 66.7% in the transgenic silkworm strain. Compared with the resistance to the Bombyx mori L. nuclear polyhedrosis virus in the Qiufeng strain, which is commonly used in the production, there was an increase of 33 centesimal points in the transgenic silkworms. The antivirotic character in the Chunhua x Qiuyue strain, which was bred from a different transgenic family, was about 10 centesimal points higher than that in the Qiufeng x Baiyu, another crossbreed used in production. Our results indicated a good application value of the transposon-inserted mutation in the breeding of anti-BmNPV silkworm strain.

SilkPathDB: a comprehensive resource for the study of silkworm pathogens.

PubMed

Li, Tian; Pan, Guo-Qing; Vossbrinck, Charles R; Xu, Jin-Shan; Li, Chun-Feng; Chen, Jie; Long, Meng-Xian; Yang, Ming; Xu, Xiao-Fei; Xu, Chen; Debrunner-Vossbrinck, Bettina A; Zhou, Ze-Yang

2017-01-01

Silkworm pathogens have been heavily impeding the development of sericultural industry and play important roles in lepidopteran ecology, and some of which are used as biological insecticides. Rapid advances in studies on the omics of silkworm pathogens have produced a large amount of data, which need to be brought together centrally in a coherent and systematic manner. This will facilitate the reuse of these data for further analysis. We have collected genomic data for 86 silkworm pathogens from 4 taxa (fungi, microsporidia, bacteria and viruses) and from 4 lepidopteran hosts, and developed the open-access Silkworm Pathogen Database (SilkPathDB) to make this information readily available. The implementation of SilkPathDB involves integrating Drupal and GBrowse as a graphic interface for a Chado relational database which houses all of the datasets involved. The genomes have been assembled and annotated for comparative purposes and allow the search and analysis of homologous sequences, transposable elements, protein subcellular locations, including secreted proteins, and gene ontology. We believe that the SilkPathDB will aid researchers in the identification of silkworm parasites, understanding the mechanisms of silkworm infections, and the developmental ecology of silkworm parasites (gene expression) and their hosts. http://silkpathdb.swu.edu.cn. © The Author(s) 2017. Published by Oxford University Press.

SilkPathDB: a comprehensive resource for the study of silkworm pathogens

PubMed Central

Pan, Guo-Qing; Vossbrinck, Charles R.; Xu, Jin-Shan; Li, Chun-Feng; Chen, Jie; Long, Meng-Xian; Yang, Ming; Xu, Xiao-Fei; Xu, Chen; Debrunner-Vossbrinck, Bettina A.

2017-01-01

Silkworm pathogens have been heavily impeding the development of sericultural industry and play important roles in lepidopteran ecology, and some of which are used as biological insecticides. Rapid advances in studies on the omics of silkworm pathogens have produced a large amount of data, which need to be brought together centrally in a coherent and systematic manner. This will facilitate the reuse of these data for further analysis. We have collected genomic data for 86 silkworm pathogens from 4 taxa (fungi, microsporidia, bacteria and viruses) and from 4 lepidopteran hosts, and developed the open-access Silkworm Pathogen Database (SilkPathDB) to make this information readily available. The implementation of SilkPathDB involves integrating Drupal and GBrowse as a graphic interface for a Chado relational database which houses all of the datasets involved. The genomes have been assembled and annotated for comparative purposes and allow the search and analysis of homologous sequences, transposable elements, protein subcellular locations, including secreted proteins, and gene ontology. We believe that the SilkPathDB will aid researchers in the identification of silkworm parasites, understanding the mechanisms of silkworm infections, and the developmental ecology of silkworm parasites (gene expression) and their hosts. Database URL: http://silkpathdb.swu.edu.cn PMID:28365723

Nutrigenetic screening strains of the mulberry silkworm, Bombyx mori, for nutritional efficiency.

PubMed

Ramesha, Chinnaswamy; Lakshmi, Hothur; Kumari, Savarapu Sugnana; Anuradha, Chevva M; Kumar, Chitta Suresh

2012-01-01

The activity of sericulture is declining due the reduction of mulberry production area in sericulture practicing countries lead to adverse effects on silkworm rearing and cocoon production. Screening for nutrigenetic traits in silkworm, Bombyx mori L. (Lepidoptera: Bombycidae) is an essential prerequisite for better understanding and development of nutritionally efficient breeds/hybrids, which show less food consumption with higher efficiency conversion. The aim of this study was to identify nutritionally efficient polyvoltine silkworm strains using the germplasm breeds RMW(2), RMW(3), RMW(4), RMG(3), RMG(1), RMG(4), RMG(5), RMG(6) and APM(1) as the control. The 1(st) day of 5(th) stage silkworm larvae of polyvoltine strains were subjected to standard gravimetric analysis until spinning for three consecutive generations covering 3 different seasons on 19 nutrigenetic traits. Highly significant (p ≤ 0.001) differences were found among all nutrigenetic traits of polyvoltine silkworm strains in the experimental groups. The nutritionally efficient polvoltine silkworm strains were resulted by utilizing nutrition consumption index and efficiency of conversion of ingesta/cocoon traits as the index. Higher nutritional efficiency conversions were found in the polyvoltine silkworm strains on efficiency of conversion of ingesta to cocoon and shell than control. Comparatively smaller consumption index, respiration, metabolic rate with superior relative growth rate, and quantum of food ingesta and digesta requisite per gram of cocoon and shell were found; the lowest amount was in new polyvoltine strains compared to the control. Furthermore, based on the overall nutrigenetic traits utilized as index or 'biomarkers', three polyvoltine silkworm strains (RMG(4), RMW(2), and RMW(3)) were identified as having the potential for nutrition efficiency conversion. The data from the present study advances our knowledge for the development of nutritionally efficient silkworm breeds

Nutrigenetic screening strains of the mulberry silkworm, Bombyx mori, for nutritional efficiency.

PubMed

Chinnaswamy, Ramesha; Lakshmi, Hothur; Kumari, Savarapu S; Anuradha, Chebba M; Kumar, Chitta S

2012-01-01

The activity of sericulture is declining due the reduction of mulberry production area in sericulture practicing countries lead to adverse effects on silkworm rearing and cocoon production. Screening for nutrigenetic traits in silkworm, Bombyx mori L. (Lepidoptera: Bombycidae) is an essential prerequisite for better understanding and development of nutritionally efficient breeds/hybrids, which show less food consumption with higher efficiency conversion. The aim of this study was to identify nutritionally efficient polyvoltine silkworm strains using the germplasm breeds RMW(2), RMW(3), RMW(4), RMG(3), RMG(1), RMG(4), RMG(5), RMG(6) and APM(1) as the control. The 1(st) day of 5(th) stage silkworm larvae of polyvoltine strains were subjected to standard gravimetric analysis until spinning for three consecutive generations covering three different seasons on 19 nutrigenetic traits. Highly significant (p ≤ 0.001) differences were found among all nutrigenetic traits of polyvoltine silkworm strains in the experimental groups. The nutritionally efficient polvoltine silkworm strains were resulted by utilizing nutrition consumption index and efficiency of conversion of ingesta/cocoon traits as the index. Higher nutritional efficiency conversions were found in the polyvoltine silkworm strains on efficiency of conversion of ingesta to cocoon and shell than control. Comparatively smaller consumption index, respiration, metabolic rate with superior relative growth rate, and quantum of food ingesta and digesta requisite per gram of cocoon and shell were shown; the lowest amount was in new polyvoltine strains compared to the control. Furthermore, based on the overall nutrigenetic traits utilized as index or 'biomarkers', three polyvoltine silkworm strains (RMG(4), RMW(2), and RMW(3)) were identified as having the potential for nutrition efficiency conversion. The data from the present study advances our knowledge for the development of nutritionally efficient silkworm breeds

Nutrigenetic Screening Strains of the Mulberry Silkworm, Bombyx mori, for Nutritional Efficiency

PubMed Central

Chinnaswamy, Ramesha; Lakshmi, Hothur; Kumari, Savarapu S.; Anuradha, Chebba M.; Kumar, Chitta S.

2012-01-01

The activity of sericulture is declining due the reduction of mulberry production area in sericulture practicing countries lead to adverse effects on silkworm rearing and cocoon production. Screening for nutrigenetic traits in silkworm, Bombyx mori L. (Lepidoptera: Bombycidae) is an essential prerequisite for better understanding and development of nutritionally efficient breeds/hybrids, which show less food consumption with higher efficiency conversion. The aim of this study was to identify nutritionally efficient polyvoltine silkworm strains using the germplasm breeds RMW2, RMW3, RMW4, RMG3, RMG1, RMG4, RMG5, RMG6 and APM1 as the control. The 1st day of 5th stage silkworm larvae of polyvoltine strains were subjected to standard gravimetric analysis until spinning for three consecutive generations covering three different seasons on 19 nutrigenetic traits. Highly significant (p ≤ 0.001) differences were found among all nutrigenetic traits of polyvoltine silkworm strains in the experimental groups. The nutritionally efficient polvoltine silkworm strains were resulted by utilizing nutrition consumption index and efficiency of conversion of ingesta/cocoon traits as the index. Higher nutritional efficiency conversions were found in the polyvoltine silkworm strains on efficiency of conversion of ingesta to cocoon and shell than control. Comparatively smaller consumption index, respiration, metabolic rate with superior relative growth rate, and quantum of food ingesta and digesta requisite per gram of cocoon and shell were shown; the lowest amount was in new polyvoltine strains compared to the control. Furthermore, based on the overall nutrigenetic traits utilized as index or ‘biomarkers’, three polyvoltine silkworm strains (RMG4, RMW2, and RMW3) were identified as having the potential for nutrition efficiency conversion. The data from the present study advances our knowledge for the development of nutritionally efficient silkworm breeds/hybrids and their

Nutrigenetic Screening Strains of the Mulberry Silkworm, Bombyx mori, for Nutritional Efficiency

PubMed Central

Ramesha, Chinnaswamy; Lakshmi, Hothur; Kumari, Savarapu Sugnana; Anuradha, Chevva M.; Kumar, Chitta Suresh

2012-01-01

The activity of sericulture is declining due the reduction of mulberry production area in sericulture practicing countries lead to adverse effects on silkworm rearing and cocoon production. Screening for nutrigenetic traits in silkworm, Bombyx mori L. (Lepidoptera: Bombycidae) is an essential prerequisite for better understanding and development of nutritionally efficient breeds/hybrids, which show less food consumption with higher efficiency conversion. The aim of this study was to identify nutritionally efficient polyvoltine silkworm strains using the germplasm breeds RMW2, RMW3, RMW4, RMG3, RMG1, RMG4, RMG5, RMG6 and APM1 as the control. The 1st day of 5th stage silkworm larvae of polyvoltine strains were subjected to standard gravimetric analysis until spinning for three consecutive generations covering 3 different seasons on 19 nutrigenetic traits. Highly significant (p ≤ 0.001) differences were found among all nutrigenetic traits of polyvoltine silkworm strains in the experimental groups. The nutritionally efficient polvoltine silkworm strains were resulted by utilizing nutrition consumption index and efficiency of conversion of ingesta/cocoon traits as the index. Higher nutritional efficiency conversions were found in the polyvoltine silkworm strains on efficiency of conversion of ingesta to cocoon and shell than control. Comparatively smaller consumption index, respiration, metabolic rate with superior relative growth rate, and quantum of food ingesta and digesta requisite per gram of cocoon and shell were found; the lowest amount was in new polyvoltine strains compared to the control. Furthermore, based on the overall nutrigenetic traits utilized as index or ‘biomarkers’, three polyvoltine silkworm strains (RMG4, RMW2, and RMW3) were identified as having the potential for nutrition efficiency conversion. The data from the present study advances our knowledge for the development of nutritionally efficient silkworm breeds/hybrids and their effective

Serial analysis of gene expression in the silkworm, Bombyx mori.

PubMed

Huang, Jianhua; Miao, Xuexia; Jin, Weirong; Couble, Pierre; Mita, Kasuei; Zhang, Yong; Liu, Wenbin; Zhuang, Leijun; Shen, Yan; Keime, Celine; Gandrillon, Olivier; Brouilly, Patrick; Briolay, Jerome; Zhao, Guoping; Huang, Yongping

2005-08-01

The silkworm Bombyx mori is one of the most economically important insects and serves as a model for Lepidoptera insects. We used serial analysis of gene expression (SAGE) to derive profiles of expressed genes during the developmental life cycle of the silkworm and to create a reference for understanding silkworm metamorphosis. We generated four SAGE libraries, one from each of the four developmental stages of the silkworm. In total we obtained 257,964 SAGE tags, of which 39,485 were unique tags. Sorted by copy number, 14.1% of the unique tags were detected at a median to high level (five or more copies), 24.2% at lower levels (two to four copies), and 61.7% as single copies. Using a basic local alignment search tool on the EST database, 35% of the tags matched known silkworm expressed sequence tags. SAGE demonstrated that a number of the genes were up- or down-regulated during the four developmental phases of the egg, larva, pupa, and adult. Furthermore, we found that the generation of longer cDNA fragments from SAGE tags constituted the most efficient method of gene identification, which facilitated the analysis of a large number of unknown genes.

Biomimetic Nucleation of Hydroxyapatite Crystals Mediated by Antheraea pernyi Silk Sericin Promotes Osteogenic Differentiation of Human Bone Marrow Derived Mesenchymal Stem Cells

PubMed Central

2015-01-01

Biomacromolecules have been used as templates to grow hydroxyapatite crystals (HAps) by biomineralization to fabricate mineralized materials for potential application in bone tissue engineering. Silk sericin is a protein with features desirable as a biomaterial, such as increased hydrophilicity and biodegradation. Mineralization of the silk sericin from Antheraea pernyi (A. pernyi) silkworm has rarely been reported. Here, for the first time, nucleation of HAps on A. pernyi silk sericin (AS) was attempted through a wet precipitation method and consequently the cell viability and osteogenic differentiation of BMSCs on mineralized AS were investigated. It was found that AS mediated the nucleation of HAps in the form of nanoneedles while self-assembling into β-sheet conformation, leading to the formation of a biomineralized protein based biomaterial. The cell viability assay of BMSCs showed that the mineralization of AS stimulated cell adhesion and proliferation, showing that the resultant AS biomaterial is biocompatible. The differentiation assay confirmed that the mineralized AS significantly promoted the osteogenic differentiation of BMSCs when compared to nonmineralized AS as well as other types of sericin (B. mori sericin), suggesting that the resultant mineralized AS biomaterial has potential in promoting bone formation. This result represented the first work proving the osteogenic differentiation of BMSCs directed by silk sericin. Therefore, the biomineralization of A. pernyi silk sericin coupled with seeding BMSCs on the resultant mineralized biomaterials is a useful strategy to develop the potential application of this unexplored silk sericin in the field of bone tissue engineering. This study lays the foundation for the use of A. pernyi silk sericin as a potential scaffold for tissue engineering. PMID:24666022

Biomimetic nucleation of hydroxyapatite crystals mediated by Antheraea pernyi silk sericin promotes osteogenic differentiation of human bone marrow derived mesenchymal stem cells.

PubMed

Yang, Mingying; Shuai, Yajun; Zhang, Can; Chen, Yuyin; Zhu, Liangjun; Mao, Chuanbin; OuYang, Hongwei

2014-04-14

Biomacromolecules have been used as templates to grow hydroxyapatite crystals (HAps) by biomineralization to fabricate mineralized materials for potential application in bone tissue engineering. Silk sericin is a protein with features desirable as a biomaterial, such as increased hydrophilicity and biodegradation. Mineralization of the silk sericin from Antheraea pernyi (A. pernyi) silkworm has rarely been reported. Here, for the first time, nucleation of HAps on A. pernyi silk sericin (AS) was attempted through a wet precipitation method and consequently the cell viability and osteogenic differentiation of BMSCs on mineralized AS were investigated. It was found that AS mediated the nucleation of HAps in the form of nanoneedles while self-assembling into β-sheet conformation, leading to the formation of a biomineralized protein based biomaterial. The cell viability assay of BMSCs showed that the mineralization of AS stimulated cell adhesion and proliferation, showing that the resultant AS biomaterial is biocompatible. The differentiation assay confirmed that the mineralized AS significantly promoted the osteogenic differentiation of BMSCs when compared to nonmineralized AS as well as other types of sericin (B. mori sericin), suggesting that the resultant mineralized AS biomaterial has potential in promoting bone formation. This result represented the first work proving the osteogenic differentiation of BMSCs directed by silk sericin. Therefore, the biomineralization of A. pernyi silk sericin coupled with seeding BMSCs on the resultant mineralized biomaterials is a useful strategy to develop the potential application of this unexplored silk sericin in the field of bone tissue engineering. This study lays the foundation for the use of A. pernyi silk sericin as a potential scaffold for tissue engineering.

[Effects of silkworm pupa oil on serum lipids level and platelet function in rats].

PubMed

Yang, Xuefeng; Huang, Lianzhen; Hu, Jianping; Li, Tao

2002-08-01

To observe the effects of silkworm pupa oil on serum lipids level and platelet function in rats, according to serum TG, TC level, 40 male Wistar rats are divided into four groups (normal control group, high fat control group, silkworm pupa oil group and silkworm pupa oil + VE group). The rats are fed different diets and six weeks later, serum lipids level and platelet function are measured. The results show that (1) Compared with high fat control group, serum TC, TG, LDL-C level, AI value, Platelet aggregability, plasma TXB2 level and T/P ratio decrease significantly while HDL-C level and 6-k-PGF1 level increase in silkworm pupa oil group; (2) Serum TC, LDL-C level, T/P ratio and platelet aggregability are significantly lower in silkworm pupa oil + VE group than in silkworm pupa oil group. It is suggested that silkworm pupa oil rich in alpha-linolenic acid can reduce serum lipids level and inhibit platelet aggregation, which is more effective with the supplementation with VE.

Genetic diversity among silkworm (Bombyx mori L., Lep., Bombycidae) germplasms revealed by microsatellites.

PubMed

Li, Muwang; Shen, Li; Xu, Anying; Miao, Xuexia; Hou, Chengxiang; Sun, Pingjiang; Zhang, Yuehua; Huang, Yongping

2005-10-01

To determine genetic relationships among strains of silkworm, Bombyx mori L., 31 strains with different origins, number of generations per year, number of molts per generation, and morphological characters were studied using simple sequence repeat (SSR) markers. Twenty-six primer pairs flanking microsatellite sequences in the silkworm genome were assayed. All were polymorphic and unambiguously separated silkworm strains from each other. A total of 188 alleles were detected with a mean value of 7.2 alleles/locus (range 2-17). The average heterozygosity value for each SSR locus ranged from 0 to 0.60, and the highest one was 0.96 (Fl0516 in 4013). The mean polymorphism index content (PIC) was 0.66 (range 0.12-0.89). Unweighted pair group method with arithmetic means (UPGMA) cluster analysis of Nei's genetic distance grouped silkworm strains based on their origin. Seven major ecotypic silkworm groups were analyzed. Principal components analysis (PCA) for SSR data support their UPGMA clustering. The results indicated that SSR markers are an efficient tool for fingerprinting cultivars and conducting genetic-diversity studies in the silkworm.

Silkworm silk-based materials and devices generated using bio-nanotechnology.

PubMed

Huang, Wenwen; Ling, Shengjie; Li, Chunmei; Omenetto, Fiorenzo G; Kaplan, David L

2018-06-25

Silks are natural fibrous protein polymers that are spun by silkworms and spiders. Among silk variants, there has been increasing interest devoted to the silkworm silk of B. mori, due to its availability in large quantities along with its unique material properties. Silk fibroin can be extracted from the cocoons of the B. mori silkworm and combined synergistically with other biomaterials to form biopolymer composites. With the development of recombinant DNA technology, silks can also be rationally designed and synthesized via genetic control. Silk proteins can be processed in aqueous environments into various material formats including films, sponges, electrospun mats and hydrogels. The versatility and sustainability of silk-based materials provides an impressive toolbox for tailoring materials to meet specific applications via eco-friendly approaches. Historically, silkworm silk has been used by the textile industry for thousands of years due to its excellent physical properties, such as lightweight, high mechanical strength, flexibility, and luster. Recently, due to these properties, along with its biocompatibility, biodegradability and non-immunogenicity, silkworm silk has become a candidate for biomedical utility. Further, the FDA has approved silk medical devices for sutures and as a support structure during reconstructive surgery. With increasing needs for implantable and degradable devices, silkworm silk has attracted interest for electronics, photonics for implantable yet degradable medical devices, along with a broader range of utility in different device applications. This Tutorial review summarizes and highlights recent advances in the use of silk-based materials in bio-nanotechnology, with a focus on the fabrication and functionalization methods for in vitro and in vivo applications in the field of tissue engineering, degradable devices and controlled release systems.

Metabolomics differences between silkworms (Bombyx mori) reared on fresh mulberry (Morus) leaves or artificial diets.

PubMed

Dong, Hui-Ling; Zhang, Sheng-Xiang; Tao, Hui; Chen, Zhuo-Hua; Li, Xue; Qiu, Jian-Feng; Cui, Wen-Zhao; Sima, Yang-Hu; Cui, Wei-Zheng; Xu, Shi-Qing

2017-09-08

Silkworms (Bombyx mori) reared on artificial diets have great potential applications in sericulture. However, the mechanisms underlying the enhancement of metabolic utilization by altering silkworm nutrition are unclear. The aim of this study was to investigate the mechanisms responsible for the poor development and low silk protein synthesis efficiency of silkworms fed artificial diets. After multi-generational selection of the ingestive behavior of silkworms to artificial diets, we obtained two strains, one of which developed well and another in which almost all its larvae starved to death on the artificial diets. Subsequently, we analyzed the metabolomics of larval hemolymph by gas chromatography/liquid chromatography-mass spectrometry, and the results showed that vitamins were in critically short supply, whereas the nitrogen metabolic end product of urea and uric acid were enriched substantially, in the hemolymph of the silkworms reared on the artificial diets. Meanwhile, amino acid metabolic disorders, as well as downregulation of carbohydrate metabolism, energy metabolism, and lipid metabolism, co-occurred. Furthermore, 10 male-dominant metabolites and 27 diet-related metabolites that differed between male and female silkworms were identified. These findings provide important insights into the regulation of silkworm metabolism and silk protein synthesis when silkworms adapt to an artificial diet.

Improvement of light penetration based silkworm gender identification with confined regions of interest

NASA Astrophysics Data System (ADS)

Kamtongdee, Chakkrit; Sumriddetchkajorn, Sarun; Sa-ngiamsak, Chiranut

2013-06-01

Based on our previous work on light penetration-based silkworm gender identification, we find that unwanted optical noises scattering from the surrounding area near the silkworm pupa and the transparent support are sometimes analyzed and misinterpreted leading to incorrect silkworm gender identification. To alleviate this issue, we place a small rectangular hole on a transparent support so that it not only helps the user precisely place the silkworm pupa but also functions as a region of interest (ROI) for blocking unwanted optical noises and for roughly locating the abdomen region in the image for ease of image processing. Apart from the external ROI, we also assign a smaller ROI inside the image in order to remove strong scattering light from all edges of the external ROI and at the same time speed up our image processing operations. With only the external ROI in function, our experiment shows a measured 86% total accuracy in identifying gender of 120 silkworm pupae with a measured average processing time of 38 ms. Combining the external ROI and the image ROI together revamps the total accuracy in identifying the silkworm gender to 95% with a measured faster 18 ms processing time.

Milled non-mulberry silk fibroin microparticles as biomaterial for biomedical applications.

PubMed

Bhardwaj, Nandana; Rajkhowa, Rangam; Wang, Xungai; Devi, Dipali

2015-11-01

Silk fibroin has been widely employed in various forms as biomaterials for biomedical applications due to its superb biocompatibility and tunable degradation and mechanical properties. Herein, silk fibroin microparticles of non-mulberry silkworm species (Antheraea assamensis, Antheraea mylitta and Philosamia ricini) were fabricated via a top-down approach using a combination of wet-milling and spray drying techniques. Microparticles of mulberry silkworm (Bombyx mori) were also utilized for comparative studies. The fabricated microparticles were physico-chemically characterized for size, stability, morphology, chemical composition and thermal properties. The silk fibroin microparticles of all species were porous (∼5μm in size) and showed nearly spherical morphology with rough surface as revealed from dynamic light scattering and microscopic studies. Non-mulberry silk microparticles maintained the typical silk-II structure with β-sheet secondary conformation with higher thermal stability. Additionally, non-mulberry silk fibroin microparticles supported enhanced cell adhesion, spreading and viability of mouse fibroblasts than mulberry silk fibroin microparticles (p<0.001) as evidenced from fluorescence microscopy and cytotoxicity studies. Furthermore, in vitro drug release from the microparticles showed a significantly sustained release over 3 weeks. Taken together, this study demonstrates promising attributes of non-mulberry silk fibroin microparticles as a potential drug delivery vehicle/micro carrier for diverse biomedical applications. Copyright © 2015 Elsevier B.V. All rights reserved.

Optical penetration-based silkworm pupa gender sensor structure.

PubMed

Sumriddetchkajorn, Sarun; Kamtongdee, Chakkrit

2012-02-01

This paper proposes and experimentally demonstrates for what is believed to be the first time a highly sought-after optical structure for highly-accurate identification of the silkworm pupa gender. The key idea is to exploit a long wavelength optical beam in the red or near infrared spectrum that can effectively and safely penetrate the body of a silkworm pupa. Later on, simple image processing operations via image thresholding, blob filtering, and image inversion processes are applied in order to eliminate the unwanted image noises and at the same time highlight the gender gland. Experimental proof of concept using three 636 nm wavelength light emitting diodes, a two-dimensional web camera, an 8 bit microcontroller board, and a notebook computer shows a very high 95.6% total accuracy in identifying the gender of 45 silkworm pupae with a measured fast identification time of 96.6 ms. Other key features include low cost, low component counts, and ease of implementation and control.

Metabolism, transformation and dynamic changes of alkaloids in silkworm during feeding mulberry leaves.

PubMed

Zhang, Liwen; Bai, Yongliang; Su, Shulan; Ouyang, Zhen; Liu, Li; Pan, Gang; Qian, Dawei; Duan, Jinao

2018-06-04

Metabolism, transformation and dynamic changes of DNJ, 2-O-α-D-Gal-DNJ, fagomine, isofagomine and 4-O-β-d-Glc-fagomine from mulberry leaves in silkworms at different instars were observed. UPLC-Q/TOF-MS and UPLC-TQ/MS methods were adopted for qualitative and quantitative analysis respectively. Three species mulberry leaves were used to feed the silkworm as controls. By analyzing and comparing the content changes of DNJ, fagomine and their derivatives in silkworms and silkworm excrement at different instar, we revealed the dynamic changes, confirmed the enrichment effect of the polyhydroxy alkaloids by silkworm, and inferred the conversion process behind this effect. The experimental results indicated that DNJ and its derivatives turned into some intermediate substances in the metabolic process, and finally they converted back and the content increased. Fagomine and its derivatives interconverted into each other in the process, 4-O-β-d-Glc-fagomine transformed into fagomine, while fagomine transformed into isofagomine.

Initial ground experiments of silkworm cultures living on different feedstock for provision of high quality animal protein for human in space

NASA Astrophysics Data System (ADS)

Yang, Yunan; Tang, Liman; Tong, Ling; Liu, Yang; Liu, Hong; Li, Xiaomin

2010-09-01

Silkworm could be an alternative to provide edible animal protein in Controlled Ecological Life Support System (CELSS) for long-term manned space missions. Silkworms can consume non-edible plant residue and convert plant nutrients to high quality edible animal protein for astronauts. The preliminary investigation of silkworm culture was carried out in earth environment. The silkworms were fed with artificial silkworm diet and the leaves of stem lettuce ( Lactuca sativa L. var. angustana Irish) separately and the nutritional structure of silkworm was investigated and compared, The culture experiments showed that: (1) Stem lettuce leaves could be used as food of silkworm. The protein content of silkworm fed with lettuce leaves can reach 70% of dry mass. (2) The protein content of silkworm powder produced by the fifth instar silkworm larvae was 70%, which was similar to the protein content of silkworm pupae. The powder of the fifth instar silkworm larvae can be utilized by astronaut. (3) The biotransformation rate of silkworm larvae between the third instar and the fifth instar could reach above 70%. The biotransformation cycle of silkworm was determined as 24 days. (4) Using the stem lettuce leaves to raise silkworm, the coarse fiber content of silkworm excrements reached about 33%. The requirements of space silkworm culture equipment, feeding approaches and feeding conditions were also preliminarily designed and calculated. It is estimated that 2.2 m 3 of culture space could satisfy daily animal protein demand for seven astronauts.

Microbial shifts of the silkworm larval gut in response to lettuce leaf feeding.

PubMed

Liang, Xue; Fu, Yuming; Tong, Ling; Liu, Hong

2014-04-01

Silkworm (Bombyx mori L.) larvae were used as an ideal animal protein source for astronauts in the bioregenerative life support system (BLSS). Here, we compared the difference in bacterial communities of the silkworm larval gut between the BLSS rearing way (BRW) and the traditional rearing way (TRW) through culture-dependent approach, 16S rRNA gene analysis, and denaturing gradient gel electrophoresis (DGGE). The culture-dependent approach revealed that the numbers of gut bacteria of silkworm in the BRW significantly decreased compared with that of the TRW. The analysis of clone libraries showed that the gut microbiota in the BRW was significantly less diverse than that in the TRW. Acinetobacter and Bacteroides were dominant populations in the BRW, and Bacillus and Arcobacter dominated in the TRW. DGGE profiles confirmed the difference of silkworm gut bacterial community between two rearing ways. These results demonstrate that gut bacteria change from the BRW contributes to the decrease of silkworm physiological activity. This study increases our understanding of the change of silkworm gut microbiota in response to lettuce leaf feeding in the BRW. We could use the dominant populations to make probiotic products for nutrient absorption and disease prevention in the BLSS to improve gut microecology, as well as the yield and quality of animal protein.

Genetic diversity, molecular phylogeny and selection evidence of the silkworm mitochondria implicated by complete resequencing of 41 genomes

PubMed Central

2010-01-01

Background Mitochondria are a valuable resource for studying the evolutionary process and deducing phylogeny. A few mitochondria genomes have been sequenced, but a comprehensive picture of the domestication event for silkworm mitochondria remains to be established. In this study, we integrate the extant data, and perform a whole genome resequencing of Japanese wild silkworm to obtain breakthrough results in silkworm mitochondrial (mt) population, and finally use these to deduce a more comprehensive phylogeny of the Bombycidae. Results We identified 347 single nucleotide polymorphisms (SNPs) in the mt genome, but found no past recombination event to have occurred in the silkworm progenitor. A phylogeny inferred from these whole genome SNPs resulted in a well-classified tree, confirming that the domesticated silkworm, Bombyx mori, most recently diverged from the Chinese wild silkworm, rather than from the Japanese wild silkworm. We showed that the population sizes of the domesticated and Chinese wild silkworms both experience neither expansion nor contraction. We also discovered that one mt gene, named cytochrome b, shows a strong signal of positive selection in the domesticated clade. This gene is related to energy metabolism, and may have played an important role during silkworm domestication. Conclusions We present a comparative analysis on 41 mt genomes of B. mori and B. mandarina from China and Japan. With these, we obtain a much clearer picture of the evolution history of the silkworm. The data and analyses presented here aid our understanding of the silkworm in general, and provide a crucial insight into silkworm phylogeny. PMID:20334646

Vertebrate estrogen regulates the development of female characteristics in silkworm, Bombyx mori.

PubMed

Shen, Guanwang; Lin, Ying; Yang, Congwen; Xing, Runmiao; Zhang, Haiyan; Chen, Enxiang; Han, Chaoshan; Liu, Hongling; Zhang, Weiwei; Xia, Qingyou

2015-01-01

The vertebrate estrogens include 17-β-estradiol (E2), which has an analog in silkworm ovaries. In this study, the Bombyx mori vitellogenin gene (BmVg) was used as a biomarker to analyze the function of the E2 in silkworm. In most oviparous animals, Vg has female-specific expression. However, BmVg expression was also detected in B. mori males. Stage specific fluctuation of BmVg expression was similar in males and females, but expression levels in males were lower than in females. E2 treatment by injection or feeding of male larvae in the final instar stage induced and stimulated male BmVg transcription and protein synthesis. When silkworm ovary primordia were transplanted into males, BmVg was induced in male fat bodies. Transplanted ovaries primordia were also able to develop into ovaries and produce mature eggs. When females were treated with E2 promoted BmVg/BmVn protein accumulation in hemolymph, ovaries and eggs. However, BmVg transcription was decreased in female fat bodies. An E2 analog was identified in the hemolymph of day 3 wandering silkworms using high-performance liquid chromatography. Estradiol titers from fifth late-instar larvae to pupal stage were determined by enzyme-linked immunosorbent assay. The results suggested that silkworms synthesized a vertebrate E2 analog. This study found that E2 promoted the synthesis of BmVg, a female typical protein in silkworms. Copyright © 2014 Elsevier Inc. All rights reserved.

Calcium Oxalate Accumulation in Malpighian Tubules of Silkworm (Bombyx mori)

NASA Astrophysics Data System (ADS)

Wyman, Aaron J.; Webb, Mary Alice

2007-04-01

Silkworm provides an ideal model system for study of calcium oxalate crystallization in kidney-like organs, called Malpighian tubules. During their growth and development, silkworm larvae accumulate massive amounts of calcium oxalate crystals in their Malpighian tubules with no apparent harm to the organism. This manuscript reports studies of crystal structure in the tubules along with analyses identifying molecular constituents of tubule exudate.

Transformation of Neomycin Resistance Gene (neo(R)) into Silkworm (Bombyx mori.L.).

PubMed

Chen, Xiu; Zhao, Yun; Zhang, Feng; Peng, Wei-Ping; Feng, Xiao-Li; Huang, Jun-Ting; Lu, Chang-De

1999-01-01

Neomycin resistance gene (neo(R)) flanked by 5' and 3' regions of fibroin H-chain gene of silkworm (Bombyx mori.L.) was transferred into eggs of silkworm by gene gun in the early period of fertilization. The larvae were fed with an artificial diet containing neomycin in early 24 hours post transfettion, and some of them survived. The neo(R) encoding sequence in G(2) generation derived from the survivals was detected by Southern blotting. The results indicated that neo(R) could be used as a selective marker for studies on transgenic silkworm.

Cadmium transfer and detoxification mechanisms in a soil-mulberry-silkworm system: phytoremediation potential.

PubMed

Zhou, Lingyun; Zhao, Ye; Wang, Shuifeng

2015-11-01

Phytoremediation has been proven to be an environmentally sound alternative for the recovery of contaminated soils, and the economic profit that comes along with the process might stimulate its field use. This study investigated cadmium (Cd) transfer and detoxification mechanisms in a soil-mulberry-silkworm system to estimate the suitability of the mulberry and silkworm as an alternative method for the remediation of Cd-polluted soil; it also explored the underlying mechanisms regulating the trophic transfer of Cd. The results show that both the mulberry and silkworm have high Cd tolerance. The transfer factor suggests that the mulberry has high potential for Cd extraction from polluted soil. The subcellular distribution and chemical forms of Cd in mulberry leaves show that cell wall deposition and vacuolar compartmentalization play important role in Cd tolerance. In the presence of increasing Cd concentrations in silkworm food, detoxification mechanisms (excretion and homeostasis) were activated so that excess Cd was excreted in fecal balls, and metallothionein levels in the mid-gut, the posterior of the silk gland, and the fat body of silkworms were enhanced. And, the Cd concentrations in silk are at a low level, ranging from 0.02 to 0.21 mg kg(-1). Therefore, these mechanisms of detoxification can regulate Cd trophic transfer, and mulberry planting and silkworm breeding has high phytoremediation potential for Cd-contaminated soil.

Evaluation of innate immune stimulating activity of polysaccharides using a silkworm (Bombyx mori) muscle contraction assay.

PubMed

Fujiyuki, T; Hamamoto, H; Ishii, K; Urai, M; Kataoka, K; Takeda, T; Shibata, S; Sekimizu, K

2012-04-01

In silkworm larvae, the mature form of paralytic peptide (PP), an insect cytokine, is produced from pro-PP in association with activation of innate immune responses, resulting in slow muscle contraction. We utilized this reaction, muscle contraction in silkworms coupled with innate immunity stimulation, to quantitatively measure the innate immune stimulating activity of various natural polysaccharides. β-Glucan of Gyrophora esculenta (GE-3), fucoidan from sporophyll of Undaria pinnatifida, and curldan induced silkworm muscle contraction. We further demonstrated that GE-3 had therapeutic effects on silkworms infected by baculovirus. Based on these findings, we propose that the silkworm muscle contraction assay is useful for screening substances that stimulate innate immunity before evaluating therapeutic effectiveness in mammals.

Characterization of anti-CD20 monoclonal antibody produced by transgenic silkworms (Bombyx mori).

PubMed

Tada, Minoru; Tatematsu, Ken-ichiro; Ishii-Watabe, Akiko; Harazono, Akira; Takakura, Daisuke; Hashii, Noritaka; Sezutsu, Hideki; Kawasaki, Nana

2015-01-01

In response to the successful use of monoclonal antibodies (mAbs) in the treatment of various diseases, systems for expressing recombinant mAbs using transgenic animals or plants have been widely developed. The silkworm (Bombyx mori) is a highly domesticated insect that has recently been used for the production of recombinant proteins. Because of their cost-effective breeding and relatively easy production scale-up, transgenic silkworms show great promise as a novel production system for mAbs. In this study, we established a transgenic silkworm stably expressing a human-mouse chimeric anti-CD20 mAb having the same amino acid sequence as rituximab, and compared its characteristics with rituximab produced by Chinese hamster ovary (CHO) cells (MabThera®). The anti-CD20 mAb produced in the transgenic silkworm showed a similar antigen-binding property, but stronger antibody-dependent cell-mediated cytotoxicity (ADCC) and weaker complement-dependent cytotoxicity (CDC) compared to MabThera. Post-translational modification analysis was performed by peptide mapping using liquid chromatography/mass spectrometry. There was a significant difference in the N-glycosylation profile between the CHO- and the silkworm-derived mAbs, but not in other post-translational modifications including oxidation and deamidation. The mass spectra of the N-glycosylated peptide revealed that the observed biological properties were attributable to the characteristic N-glycan structures of the anti-CD20 mAbs produced in the transgenic silkworms, i.e., the lack of the core-fucose and galactose at the non-reducing terminal. These results suggest that the transgenic silkworm may be a promising expression system for the tumor-targeting mAbs with higher ADCC activity.

Ultrafast Screening of a Novel, Moderately Hydrophilic Angiotensin-Converting-Enzyme-Inhibitory Peptide, RYL, from Silkworm Pupa Using an Fe-Doped-Silkworm-Excrement-Derived Biocarbon: Waste Conversion by Waste.

PubMed

Liu, Long; Wei, Yanan; Chang, Qing; Sun, Huaju; Chai, Kungang; Huang, Zuqiang; Zhao, Zhenxia; Zhao, Zhongxing

2017-12-27

A novel, moderately hydrophilic peptide (RYL) with high ACE-inhibitory activity was screened ultrafast via a concept of waste conversion using waste. This novel peptide was screened from silkworm pupa using an Fe-doped porous biocarbon (FL/Z-SE) derived from silkworm excrement. FL/Z-SE possessed magnetic properties and specific selection for peptides due to Fe's dual functions. The selected RYL, which has moderate hydrophilicity (LogP = -0.22), exhibited a comparatively high ACE-inhibitory activity (IC 50 = 3.31 ± 0.11 μM). The inhibitory kinetics and docking-simulation results show that, as a competitive ACE inhibitor, RYL formed five hydrogen bonds with the ACE residues in the S1 and S2 pockets. In this work, both the screening carbon material and the selected ACE-inhibitory peptide were derived from agricultural waste (silkworm excrement and pupa), which offers a new way of thinking about the development of advanced uses of the silkworm byproducts and wastes.

[Optimization of Extraction Technology for Sericin from Silkworm Cocoon with Orthogonal Design].

PubMed

Zhao, Chun-ying; Wang, Yan; Li, Yun-feng; Chen, Zhi-hong

2015-05-01

To optimize the appropriate extracting technology for sericin from Silkworm cocoon. Using sericin extraction rates and sericin content as the indices. The single and orthogonal experiments were used to determine the best conditions. The optimal extraction technology for sericin from Silkworm cocoon was as follows: 1: 30 for the ratio of solid to liquid, 3 h reflux for 2 times of extraction and water temperature at 100 degrees C. The extraction rate of sericin from Silkworm cocoon was 27.1%. The optimal extraction technology is stable, feasible, and can provide reference for further pharmacological study on cocoon sericin.

Anti-Mycobacterium activity of microbial peptides in a silkworm infection model with Mycobacterium smegmatis.

PubMed

Yagi, Akiho; Uchida, Ryuji; Hamamoto, Hiroshi; Sekimizu, Kazuhisa; Kimura, Ken-Ichi; Tomoda, Hiroshi

2017-05-01

An in vivo-mimic silkworm infection model with Mycobacterium smegmatis was established. When silkworms were raised at 37 °C following an injection of M. smegmatis cells (1.25 × 10 7 CFU larva -1  g -1 ) into the silkworm hemolymph, they died within 48 h. Under these conditions, four microbial peptides with anti-M. smegmatis activity, lariatin A, calpinactam, lysocin E and propeptin, exerted therapeutic effects in a dose-dependent manner, and these are also clinically used agents that are active against Mycobacterium tuberculosis. These results indicate that the silkworm infection model with M. smegmatis is practically useful for the screening of therapeutically effective anti-M. tuberculosis antibiotics.

Lead in the soil-mulberry (Morus alba L.)-silkworm (Bombyx mori) food chain: translocation and detoxification.

PubMed

Zhou, Lingyun; Zhao, Ye; Wang, Shuifeng; Han, Shasha; Liu, Jing

2015-06-01

The translocation of lead (Pb) in the soil-mulberry-silkworm food chain and the process of Pb detoxification in the mulberry-silkworm chain were investigated. The amount of Pb in mulberry, silkworm, feces and silk increased in a dose-responsive manner to the Pb contents in the soils. Mulberry roots sequestered most of the Pb, ranging from 230.78 to 1209.25 mg kg(-1). Over 92% of the Pb in the mulberry leaves was deposited in the cell wall, and 95.29-95.57% of the Pb in the mulberry leaves was integrated with oxalic acid, pectates and protein, and it had low bioavailability. The Pb concentrations in the silkworm feces were 4.50-4.64 times higher than those in the leaves. The synthesis of metallothioneins in three tissues of the silkworms was induced to achieve Pb homeostasis under Pb stress. These results indicated the mechanism involved in Pb transfer along the food chain was controlled by the detoxification of Pb in different trophic levels. Planting mulberry and rearing silkworm could be a promising approach for the remediation of Pb-polluted soils due to the Pb tolerance of mulberry and silkworm. Copyright © 2015. Published by Elsevier Ltd.

Vitellogenin from the silkworm, Bombyx mori: an effective anti-bacterial agent.

PubMed

Singh, Nitin Kumar; Pakkianathan, Britto Cathrin; Kumar, Manish; Prasad, Tulika; Kannan, Mani; König, Simone; Krishnan, Muthukalingan

2013-01-01

Silkworm, Bombyx mori, vitellogenin (Vg) was isolated from perivisceral fat body of day 3 of pupa. Both Vg subunits were co-purified as verified by mass spectrometry and immunoblot. Purified Vg responded to specific tests for major posttranslational modifications on native gels indicating its nature as lipo-glyco-phosphoprotein. The Vg fraction had strong antibacterial activity against Gram negative bacterium Escherichia coli and Gram positive bacterium Bacillus subtilis. Microscopic images showed binding of Vg to bacterial cells and their destruction. When infected silkworm larvae were treated with purified Vg they survived the full life cycle in contrast to untreated animals. This result showed that Vg has the ability to inhibit the proliferation of bacteria in the silkworm fluid system without disturbing the regular metabolism of the host.

JAK/STAT signaling pathway-mediated immune response in silkworm (Bombyx mori) challenged by Beauveria bassiana.

PubMed

Geng, Tao; Lv, Ding-Ding; Huang, Yu-Xia; Hou, Cheng-Xiang; Qin, Guang-Xing; Guo, Xi-Jie

2016-12-20

Innate immunity was critical in insects defensive system and able to be induced by Janus kinase/signal transducer and activator of transcription cascade transduction (JAK/STAT) signaling pathway. Currently, it had been identified many JAK/STAT signaling pathway-related genes in silkworm, but little function was known on insect innate immunity. To explore the roles of JAK/STAT pathway in antifungal immune response in silkworm (Bombyx mori) against Beauveria bassiana infection, the expression patterns of B. mori C-type lectin 5 (BmCTL5) and genes encoding 6 components of JAK/STAT signaling pathway in silkworm challenged by B. bassiana were analyzed using quantitative real time PCR. Meanwhile the activation of JAK/STAT signaling pathway by various pathogenic micro-organisms and the affect of JAK/STAT signaling pathway inhibitors on antifungal activity in silkworm hemolymph was also detected. Moreover, RNAi assay of BmCTL5 and the affect on expression levels of signaling factors were also analyzed. We found that JAK/STAT pathway could be obviously activated in silkworm challenged with B. bassiana and had no response to bacteria and B. mori cytoplasmic polyhedrosis virus (BmCPV). However, the temporal expression patterns of JAK/STAT signaling pathway related genes were significantly different. B. mori downstream receptor kinase (BmDRK) might be a positive regulator of JAK/STAT signaling pathway in silkworm against B. bassiana infection. Moreover, antifungal activity assay showed that the suppression of JAK/STAT signaling pathway by inhibitors could significantly inhibit the antifungal activity in hemolymph and resulted in increased sensitivity of silkworm to B. bassiana infection, indicating that JAK/STAT signaling pathway might be involved in the synthesis and secretion of antifungal substances. The results of RNAi assays suggested that BmCTL5 might be one pattern recognition receptors for JAK/STAT signaling pathway in silkworm. These findings yield insights for better

Genome-wide identification and characterization of Fox genes in the silkworm, Bombyx mori.

PubMed

Song, JiangBo; Li, ZhiQuan; Tong, XiaoLing; Chen, Cong; Chen, Min; Meng, Gang; Chen, Peng; Li, ChunLin; Xin, YaQun; Gai, TingTing; Dai, FangYin; Lu, Cheng

2015-09-01

The forkhead box (Fox) transcription factor family has a characteristic of forkhead domain, a winged DNA-binding domain. The Fox genes have been classified into 23 subfamilies, designated FoxA to FoxS, of which the FoxR and FoxS subfamilies are specific to vertebrates. In this review, using whole-genome scanning, we identified 17 distinct Fox genes distributed on 13 chromosomes of the silkworm, Bombyx mori. A phylogenetic tree showed that the silkworm Fox genes could be classified into 13 subfamilies. The FoxK subfamily is specifically absent from the silkworm, although it is present in other lepidopteran insects, including Danaus plexippus and Heliconius melpomene. Microarray data revealed that the Fox genes have distinct expression patterns in the tissues on day 3 of the 5th instar larva. A Gene Ontology analysis suggested that the Fox genes have roles in cellular components, molecular functions, and biological processes, except in pore complex biogenesis. An analysis of the selective pressure on the proteins indicated that most of the amino acid sites in the Fox proteins are undergoing strong purifying selection. Here, we summarize the general characteristics of the Fox genes in the silkworm, which should support further functional studies of the silkworm Fox proteins.

Vitellogenin from the Silkworm, Bombyx mori: An Effective Anti-Bacterial Agent

PubMed Central

Kumar, Manish; Prasad, Tulika; Kannan, Mani; König, Simone

2013-01-01

Silkworm, Bombyx mori, vitellogenin (Vg) was isolated from perivisceral fat body of day 3 of pupa. Both Vg subunits were co-purified as verified by mass spectrometry and immunoblot. Purified Vg responded to specific tests for major posttranslational modifications on native gels indicating its nature as lipo-glyco-phosphoprotein. The Vg fraction had strong antibacterial activity against Gram negative bacterium Escherichia coli and Gram positive bacterium Bacillus subtilis. Microscopic images showed binding of Vg to bacterial cells and their destruction. When infected silkworm larvae were treated with purified Vg they survived the full life cycle in contrast to untreated animals. This result showed that Vg has the ability to inhibit the proliferation of bacteria in the silkworm fluid system without disturbing the regular metabolism of the host. PMID:24058454

Fabrication and characterization of biomaterial film from gland silk of muga and eri silkworms.

PubMed

Dutta, Saranga; Talukdar, Bijit; Bharali, Rupjyoti; Rajkhowa, Rangam; Devi, Dipali

2013-05-01

This study discusses the possibilities of liquid silk (Silk gland silk) of Muga and Eri silk, the indigenous non mulberry silkworms of North Eastern region of India, as potential biomaterials. Silk protein fibroin of Bombyx mori, commonly known as mulberry silkworm, has been extensively studied as a versatile biomaterial. As properties of different silk-based biomaterials vary significantly, it is important to characterize the non mulberry silkworms also in this aspect. Fibroin was extracted from the posterior silk gland of full grown fifth instars larvae, and 2D film was fabricated using standard methods. The films were characterized using SEM, Dynamic contact angle test, FTIR, XRD, DSC, and TGA and compared with respective silk fibers. SEM images of films reveal presence of some globules and filamentous structure. Films of both the silkworms were found to be amorphous with random coil conformation, hydrophobic in nature, and resistant to organic solvents. Non mulberry silk films had higher thermal resistance than mulberry silk. Fibers were thermally more stable than the films. This study provides insight into the new arena of research in application of liquid silk of non mulberry silkworms as biomaterials. Copyright © 2012 Wiley Periodicals, Inc.

Comparative proteomic analysis reveals the suppressive effects of dietary high glucose on the midgut growth of silkworm.

PubMed

Feng, Fan; Chen, Liang; Lian, Chaoqun; Xia, Hengchuan; Zhou, Yang; Yao, Qin; Chen, Keping

2014-08-28

The silkworm, Bombyx mori, is an important model of lepidoptera insect, and it has been used for several models of human diseases. In human being, long-term high-sugar diet can induce the occurrence of diabetes and other related diseases. Interestingly, our experiments revealed the high glucose diet also has a suppressive effect on the development of silkworms. To investigate the molecular mechanism by which high-glucose diet inhibited the midgut growth in silkworms, we employed comparative proteomic analysis to globally identify proteins differentially expressed in normal and high-glucose diet group silkworms. In all, 28 differently proteins were suppressed and 5 proteins induced in high-glucose diet group. Gene ontology analysis showed that most of these differently proteins are mainly involved in metabolic process, catalytic and cellular process. A development related protein, imaginal disk growth factor (IDGF), was further confirmed by western blot exclusively expressing in the normal diet group silkworms. Taken together, our data suggests that IDGF plays a critical role in impairing the development of silkworms by a high-glucose diet. Glucose has been thought to play essential roles in growth and development of silkworm. In this paper, we certified firstly that high-glucose diet can suppress the growth of silkworm, and comparative proteomic was employed to reveal the inhibition mechanism. Moreover, an important regulation related protein (IDGF) was found to involve in this inhibition process. These results will help us get a deeper understanding of the relationship between diet and healthy. Furthermore, IDGF may be the critical protein for reducing the blood sugar in silkworm, and it may be used for screening human hypoglycemic drug. The work has not been submitted elsewhere for publication, in whole or in part, and all the authors have approved the manuscript. Copyright © 2014 Elsevier B.V. All rights reserved.

Identification and characterization of an arginine kinase as a major allergen from silkworm (Bombyx mori) larvae.

PubMed

Liu, Zhigang; Xia, Lixin; Wu, Yulan; Xia, Qingyou; Chen, Jiajie; Roux, Kenneth H

2009-01-01

The silkworm, Bombyx mori, is an important insect in the textile industry and its pupa are used in Chinese cuisine and traditional Chinese medicine. The silk, urine and dander of silkworms is often the cause of allergies in sericulture workers and the pupa has been found to be a food allergen in China. Recent studies have focused on reporting cases of silkworm allergies, but only a few studies have addressed the specific allergens present in the B. mori silkworm. We collected sera from 10 patients with a positive skin prick test to silkworm crude extract (SCE) and analyzed these samples by Western blot and ELISA. The cDNA of arginine kinase from the B. mori silkworm was also cloned and expressed in high yield in Escherichia coli. Allergenicity and cross-allergenicity of the recombinant B. mori arginine kinase (rBmAK) were investigated by ELISA inhibition assay. Collected sera all reacted to a 42-kDa protein in a Western blot with SCE as the antigen. Preincubation of sera with rBmAK eliminated the reactivity of the patients' sera to this 42-kDa band. All patient sera also exhibited positive reactivity to SCE in an ELISA assay. BmAK also demonstrated cross-reactivity with a recombinant AK from cockroach. Arginine kinase from the B. mori silkworm is a major allergen and crossreacts with cockroach AK. Copyright 2009 S. Karger AG, Basel.

Spatiotemporal expression profile of the Pumilio gene in the embryonic development of silkworm.

PubMed

Chen, Liang; You, Zaizhi; Xia, Hengchuan; Tang, Qi; Zhou, Yang; Yao, Qin; Chen, Keping

2014-01-01

We previously identified a pumilio gene in silkworm (Bombyx mori L.), designated BmPUM, which was specifically expressed in the ovary and testis. To further characterize this gene's involvement in silkworm development, we have determined the spatiotemporal expression pattern of BmPUM during all embryonic stages. Real-time polymerase chain reaction (RT-PCR) analysis revealed that BmPUM was expressed in all stages of silkworm embryos and that its transcript levels displayed two distinct peaks. The first was observed at the germ-band formation stage (1 d after oviposition) and dropped to a low level at the gonad formation stage (5 d after oviposition). The second was detected at the stage of bristle follicle occurrence (6 d after oviposition), which was confirmed by Western blot analysis and immunohistochemistry. Nanos (Nos), functioning together with Pum in abdomen formation of Drosophila embryos, was also highly expressed at the beginning (0 h to 1 d after oviposition) of embryogenesis, but its transcript levels were very low after the stage of germ-band formation. These results suggest that BmPUM functions with Bombyx mori nanos (Bm-nanos) at the early stages of silkworm embryonic development, and may then play a role in gonad formation and the occurrence of bristle follicles. Our data thus provide a foundation to uncover the role of BmPUM during silkworm development.

iTRAQ-based quantitative proteomic analysis of midgut in silkworm infected with Bombyx mori cytoplasmic polyhedrosis virus.

PubMed

Gao, Kun; Deng, Xiang-Yuan; Shang, Meng-Ke; Qin, Guang-Xing; Hou, Cheng-Xiang; Guo, Xi-Jie

2017-01-30

Bombyx mori cytoplasmic polyhedrosis virus (BmCPV) specifically infects the epithelial cells in the midgut of silkworm and causes them to death, which negatively affects the sericulture industry. In order to determine the midgut response at the protein levels to the virus infection, differential proteomes of the silkworm midgut responsive to BmCPV infection were identified with isobaric tags for relative and absolute quantitation (iTRAQ) labeling followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). 193, 408, 189 differentially expressed proteins (DEPs) were reliably quantified by iTRAQ analysis in the midgut of BmCPV-infected and control larvae at 24, 48, 72h post infection (hpi) respectively. KEGG enrichment analysis showed that Oxidative phosphorylation, amyotrophic lateral sclerosis, Toll-like receptor signaling pathway, steroid hormone biosynthesis were the significant pathways (Q value≤0.05) both at 24 and 48hpi. qRT-PCR was used to further verify gene transcription of 30 DEPs from iTRAQ, showing that the regulations of 24 genes at the transcript level were consistent with those at the proteomic level. Moreover, the cluster analysis of the three time groups showed that there were seven co-regulated DEPs including BGIBMGA002620-PA, which was a putative p62/sequestosome-1 protein in silkworm. It was upregulated at both the mRNA level and the proteomic level and may play an important role in regulating the autophagy and apoptosis (especially apoptosis) induced by BmCPV infection. This was the first report using an iTRAQ approach to analyze proteomes of the silkworm midgut against BmCPV infection, which contributes to understanding the defense mechanisms of silkworm midgut to virus infection. The domesticated silkworm, Bombyx mori, is renowned for silk production as well as being a traditional lepidopteron model insect served as a subject for morphological, genetic, physiological, and developmental studies. Bombyx mori cytoplasmic polyhedrosis

Eri silkworm: a source of edible oil with a high content of α-linolenic acid and of significant nutritional value.

PubMed

Longvah, Thingnganing; Manghtya, Korra; Qadri, Syed S Y H

2012-07-01

The study was undertaken to provide value addition to spent eri silkworm as an alternative source of edible oil for the food and feed industry by carrying out a short-term nutritional and toxicological evaluation of eri silkworm pupae oil using Wistar NIN rats. Growth performance of rats fed either sunflower oil (Control) or eri silkworm pupae oil (Experimental) was comparable. Histopathological examination of the various tissues showed no signs of toxicity even after feeding the eri silkworm oil for 18 weeks. Serum cholesterol and triglyceride was significantly reduced (P < 0.05) while high-density lipoprotein cholesterol was significantly increased (P < 0.05) which is attributed to the high α-linolenic acid content of eri silkworm oil. The study showed that eri silkworm pupae oil is safe and nutritionally equivalent to commonly used vegetable oils. Eri silkworm pupae can be harvested to provide a cost effective alternative edible oil that can be used to nutritional advantage in the food and feed industry. Therefore eri silkworm and its host plants offer an excellent example of multiple product crops and of sustainable agricultural practice with excellent opportunity for economic and nutritional benefits. Copyright © 2012 Society of Chemical Industry.

Allergenic Characterization of 27-kDa Glycoprotein, a Novel Heat Stable Allergen, from the Pupa of Silkworm, Bombyx mori.

PubMed

Jeong, Kyoung Yong; Son, Mina; Lee, June Yong; Park, Kyung Hee; Lee, Jae-Hyun; Park, Jung-Won

2016-01-01

Boiled silkworm pupa is a traditional food in Asia, and patients with silkworm pupa food allergy are common in these regions. Still now only one allergen from silkworm, arginine kinase, has been identified. The purpose of this study was to identify novel food allergens in silkworm pupa by analyzing a protein extract after heat treatment. Heat treated extracts were examined by proteomic analysis. A 27-kDa glycoprotein was identified, expressed in Escherichia coli, and purified. IgE reactivity of the recombinant protein was investigated by ELISA. High molecular weight proteins (above 100 kDa) elicited increased IgE binding after heat treatment compared to that before heat treatment. The molecular identities of these proteins, however, could not be determined. IgE reactivity toward a 27-kDa glycoprotein was also increased after heating the protein extract. The recombinant protein was recognized by IgE antibodies from allergic subjects (33.3%). Glycation or aggregation of protein by heating may create new IgE binding epitopes. Heat stable allergens are shown to be important in silkworm allergy. Sensitization to the 27-kDa glycoprotein from silkworm may contribute to elevation of IgE to silkworm.

Allergenic Characterization of 27-kDa Glycoprotein, a Novel Heat Stable Allergen, from the Pupa of Silkworm, Bombyx mori

PubMed Central

Son, Mina; Lee, June Yong

2016-01-01

Boiled silkworm pupa is a traditional food in Asia, and patients with silkworm pupa food allergy are common in these regions. Still now only one allergen from silkworm, arginine kinase, has been identified. The purpose of this study was to identify novel food allergens in silkworm pupa by analyzing a protein extract after heat treatment. Heat treated extracts were examined by proteomic analysis. A 27-kDa glycoprotein was identified, expressed in Escherichia coli, and purified. IgE reactivity of the recombinant protein was investigated by ELISA. High molecular weight proteins (above 100 kDa) elicited increased IgE binding after heat treatment compared to that before heat treatment. The molecular identities of these proteins, however, could not be determined. IgE reactivity toward a 27-kDa glycoprotein was also increased after heating the protein extract. The recombinant protein was recognized by IgE antibodies from allergic subjects (33.3%). Glycation or aggregation of protein by heating may create new IgE binding epitopes. Heat stable allergens are shown to be important in silkworm allergy. Sensitization to the 27-kDa glycoprotein from silkworm may contribute to elevation of IgE to silkworm. PMID:26770033

Functions and substrates of NEDDylation during cell cycle in the silkworm, Bombyx mori.

PubMed

Li, Zhiqing; Cui, Qixin; Wang, Xiaoyan; Li, Bingqian; Zhao, Dongchao; Xia, Qingyou; Zhao, Ping

2017-11-01

NEDDylation, a post-translational modification mediated by the conjugation of the ubiquitin-like protein Nedd8 to specific substrates, is an essential biological process that regulates cell cycle progression in eukaryotes. Here, we report the conservation of NEDDylation machinery and NEDDylated proteins in the silkworm, Bombyx mori. We have identified all the components necessary for reversible NEDDylation in the silkworm including Nedd8, E1, E2, E3, and deNEDDylation enzymes. By the approach of RNAi-mediated gene silencing, it was shown that knockdown of BmNedd8 and the conjugating enzymes decreased the global level of NEDDylation, while knockdown of deNEDDylation enzymes increased the prevalence of this modification in cultured silkworm cells. Moreover, the lack of the NEDDylation system caused cell cycle arrest at the G2/M phase and resulted in defects in chromosome congression and segregation. Using the wild-type and mutants of BmNedd8, we identified the specific substrates of BmNedd8, which are involved in the regulation for many cellular processes, including ribosome biogenesis, spliceosome structure, spindle formation, metabolism, and RNA biogenesis. This clearly demonstrates that the NEDDylation system is able to control multiple pathways in the silkworm. Altogether, the information on the functions and substrates of the NEDDylation system presented here could provide a basis for future investigations of protein NEDDylation and its regulatory mechanism on cell cycle progression in the silkworm. Copyright © 2017. Published by Elsevier Ltd.

Evaluation of drug-induced tissue injury by measuring alanine aminotransferase (ALT) activity in silkworm hemolymph

PubMed Central

2012-01-01

Background Our previous studies suggest silkworms can be used as model animals instead of mammals in pharmacologic studies to develop novel therapeutic medicines. We examined the usefulness of the silkworm larvae Bombyx mori as an animal model for evaluating tissue injury induced by various cytotoxic drugs. Drugs that induce hepatotoxic effects in mammals were injected into the silkworm hemocoel, and alanine aminotransferase (ALT) activity was measured in the hemolymph 1 day later. Results Injection of CCl4 into the hemocoel led to an increase in ALT activity. The increase in ALT activity was attenuated by pretreatment with N-acetyl-L-cysteine. Injection of benzoic acid derivatives, ferric sulfate, sodium valproate, tetracycline, amiodarone hydrochloride, methyldopa, ketoconazole, pemoline (Betanamin), N-nitroso-fenfluramine, and D-galactosamine also increased ALT activity. Conclusions These findings indicate that silkworms are useful for evaluating the effects of chemicals that induce tissue injury in mammals. PMID:23137391

Sericin Composition in the Silk of Antheraea yamamai.

PubMed

Zurovec, Michal; Yonemura, Naoyuki; Kludkiewicz, Barbara; Sehnal, František; Kodrik, Dalibor; Vieira, Ligia Cota; Kucerova, Lucie; Strnad, Hynek; Konik, Peter; Sehadova, Hana

2016-05-09

The silks produced by caterpillars consist of fibroin proteins that form two core filaments, and sericin proteins that seal filaments into a fiber and conglutinate fibers in the cocoon. Sericin genes are well-known in Bombyx mori (Bombycidae) but have received little attention in other insects. This paper shows that Antheraea yamamai (Saturniidae) contains five sericin genes very different from the three sericin genes of B. mori. In spite of differences, all known sericins are characterized by short exons 1 and 2 (out of 3-12 exons), expression in the middle silk gland section, presence of repeats with high contents of Ser and charged amino acid residues, and secretion as a sticky silk component soluble in hot water. The B. mori sericins represent tentative phylogenetic lineages (I) BmSer1 and orthologs in Saturniidae, (II) BmSer2, and (III) BmSer3 and related sericins of Saturniidae and of the pyralid Galleria mellonella. The lineage (IV) seems to be limited to Saturniidae. Concerted evolution of the sericin genes was apparently associated with gene amplifications as well as gene loses. Differences in the silk fiber morphology indicate that the cocktail of sericins linking the filaments and coating the fiber is modified during spinning. Silks are composite biomaterials of conserved function in spite of great diversity of their composition.

Transcriptome Analysis of Thermal Parthenogenesis of the Domesticated Silkworm.

PubMed

Liu, Peigang; Wang, Yongqiang; Du, Xin; Yao, Lusong; Li, Fengbo; Meng, Zhiqi

2015-01-01

Thermal induction of parthenogenesis (also known as thermal parthenogenesis) in silkworms is an important technique that has been used in artificial insemination, expansion of hybridization, transgenesis and sericultural production; however, the exact mechanisms of this induction remain unclear. This study aimed to investigate the gene expression profile in silkworms undergoing thermal parthenogenesis using RNA-seq analysis. The transcriptome profiles indicated that in non-induced and induced eggs, the numbers of differentially expressed genes (DEGs) for the parthenogenetic line (PL) and amphigenetic line (AL) were 538 and 545, respectively, as determined by fold-change ≥ 2. Gene ontology (GO) analysis showed that DEGs between two lines were mainly involved in reproduction, formation of chorion, female gamete generation and cell development pathways. Upregulation of many chorion genes in AL suggests that the maturation rate of AL eggs was slower than PL eggs. Some DEGs related to reactive oxygen species removal, DNA repair and heat shock response were differentially expressed between the two lines, such as MPV-17, REV1 and HSP68. These results supported the view that a large fraction of genes are differentially expressed between PL and AL, which offers a new approach to identifying the molecular mechanism of silkworm thermal parthenogenesis.

Transcriptome Analysis of Thermal Parthenogenesis of the Domesticated Silkworm

PubMed Central

Du, Xin; Yao, Lusong; Li, Fengbo; Meng, Zhiqi

2015-01-01

Thermal induction of parthenogenesis (also known as thermal parthenogenesis) in silkworms is an important technique that has been used in artificial insemination, expansion of hybridization, transgenesis and sericultural production; however, the exact mechanisms of this induction remain unclear. This study aimed to investigate the gene expression profile in silkworms undergoing thermal parthenogenesis using RNA-seq analysis. The transcriptome profiles indicated that in non-induced and induced eggs, the numbers of differentially expressed genes (DEGs) for the parthenogenetic line (PL) and amphigenetic line (AL) were 538 and 545, respectively, as determined by fold-change ≥ 2. Gene ontology (GO) analysis showed that DEGs between two lines were mainly involved in reproduction, formation of chorion, female gamete generation and cell development pathways. Upregulation of many chorion genes in AL suggests that the maturation rate of AL eggs was slower than PL eggs. Some DEGs related to reactive oxygen species removal, DNA repair and heat shock response were differentially expressed between the two lines, such as MPV-17, REV1 and HSP68. These results supported the view that a large fraction of genes are differentially expressed between PL and AL, which offers a new approach to identifying the molecular mechanism of silkworm thermal parthenogenesis. PMID:26274803

Sublethal dose of phoxim and Bombyx mori nucleopolyhedrovirus interact to elevate silkworm mortality.

PubMed

Gu, ZhiYa; Li, FanChi; Hu, JingSheng; Ding, Chao; Wang, Chaoqian; Tian, JiangHai; Xue, Bin; Xu, KaiZun; Shen, WeiDe; Li, Bing

2017-03-01

Silkworm (Bombyx mori) is an economically important insect. It is relatively less resistant to certain chemicals and environment exposures such as pesticides and pathogens. After pesticide exposures, the silkworms are more susceptible to microbial infections. The mechanism underlying the susceptibility might be related to immune response and oxidative stress. A sublethal dose of phoxim combined with Bombyx mori nucleopolyhedrovirus (BmNPV) elevated the silkworm mortality at 96 h. We found a higher content of H 2 O 2 and increased levels of genes related to oxidative stress and immune response after treatment with a sublethal dose of phoxim for 24 h or 48 h. However, such response decreased with longer pesticide treatment. Mortality increased by 44% when B. mori was exposed to combined treatment with BmNPV and phoxim rather than BmNPV alone. The level of examined immune-related and oxidative-stress-related genes significantly decreased in the combined treatment group compared with the BmNPV group. Our results indicated that, with long-term exposure to pesticides such as OPs, even at sublethal dose, the oxidative stress response and immune responses in silkworm were inhibited, which may lead to further immune impairment and accumulation of oxidative stress, resulting in susceptibility to the virus and harm to the silkworm. Our study provided insights for understanding the susceptibility to pathogen after pesticide exposures, which may promote the development of better pesticide controls to avoid significant economic losses. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Variation of lifespan in multiple strains, and effects of dietary restriction and BmFoxO on lifespan in silkworm, Bombyx mori.

PubMed

Song, Jiangbo; Tang, Dongmei; Li, Zhiquan; Tong, Xiaoling; Zhang, Jianfei; Han, Minjin; Hu, Hai; Lu, Cheng; Dai, Fangyin

2017-01-31

Established animal models have accelerated our understanding of the mechanisms involved in lifespan determination. However, more experimental animals are required to clarify the complex mechanisms behind the phenomena of aging and lifespan. In this study, we reported the variation of lifespan in nine distinct silkworm strains. Lifespan correlated significantly with BmFoxO gene expression in the representative silkworm strains tested (Xiafang, Dazao-N, and N4). In general, the female silkworm was longer lived than the male of the same strain. Dietary restriction extended the silkworm lifespan compared with that of silkworms fed ad libitum. The expression of BmFoxO was significantly elevated in the dietary restriction group on day 3 of the 4th instar and day 3 of the 5th instar, suggesting that BmFoxO contributes to dietary restriction-mediated lifespan extension. The RNA interference and overexpression of the BmFoxO gene significantly shortened and extended the silkworm adulthood, respectively. In conclusion, our findings suggest that the silkworm might serve as a promising experimental animal to explore the complex biological mechanisms of lifespan determination.

Seasonal Variation in Food Consumption, Assimilation, and Conversion Efficiency of Indian Bivoltine Hybrid Silkworm, Bombyx mori

PubMed Central

Rahmathulla, V. K.; Suresh, H. M.

2012-01-01

Food consumption and utilization is influenced by various biotic and abiotic factors. Under different environmental, feeding, and nutritional conditions, and with ingestion of the same amount of mulberry leaves, the silkworm shows significant difference in its ability to digest, absorb, and convert food to body matter. Here, influences of season, temperature, and humidity on food intake, assimilation, and conversion efficiency of the Indian bivoltine hybrid (CSR2 × CSR4) Bombyx mori L. (Lepidoptera: Bombycidae) were studied. The results indicated that food ingestion and assimilation were significantly higher among silkworm batches where optimum temperature and humidity were maintained compared with silkworm batches exposed to natural climatic conditions of the respective season. However, during summer the nutritional efficiency parameters were significantly higher among silkworms reared under natural temperature and humidity conditions when compared with the control. During the winter and rainy season, the nutritional efficiency parameters were significantly higher in control batches, where optimum temperature and humidity were maintained. Ingesta and digesta required to produce one gram of cocoon/shell were also lower in control batches for all seasons except summer. This may be due to the physiological adaptation of silkworms to overcome stress during the summer season. PMID:23414194

Postoperative anti-adhesion ability of a novel carboxymethyl chitosan from silkworm pupa in a rat cecal abrasion model.

PubMed

Zhu, Lin; Zhang, Yu-Qing

2016-04-01

N,O-Carboxymethyl chitosan (NOCC) can prevent postsurgical adhesion formation. Here, we described the preparation of a novel silkworm pupa NOCC and its effects on the prevention of postoperative adhesion in a rat cecal abrasion model. The degree of deacetylation (DDA) of silkworm pupa chitosan was only 49.87 ± 0.86%; regardless, it was used as the raw material to construct the novel silkworm pupa NOCC, which had a weaker crystallinity than the NOCC standard. Sixty male Sprague-Dawley rats were divided into three groups and treated as follows: 0.9% normal saline solution as a negative control, medical anti-adhesion gel as a positive control and the silkworm pupa NOCC anti-adhesion solution. Two and three weeks after surgery, the animals were killed and the adhesion formation was scored. The silkworm pupa NOCC solution significantly decreased the levels of WBC, TNF-α, IL-1β, IL-2, IL-6 and IL-8 but had no effect on IL-4. Additionally, a lower level of TGF-β1 expression was found in the silkworm pupa NOCC group, and significantly less collagen (P<0.01) and fewer inflammatory cells and fibroblasts were detected in the animals of this group. These results suggested that the novel NOCC from silkworm pupa using the method described here have potential applications in the prevention of postoperative intestinal adhesion. Copyright © 2015 Elsevier B.V. All rights reserved.

Development of chemical isotope labeling liquid chromatography mass spectrometry for silkworm hemolymph metabolomics.

PubMed

Shen, Weifeng; Han, Wei; Li, Yunong; Meng, Zhiqi; Cai, Leiming; Li, Liang

2016-10-26

Silkworm (Bombyx mori) is a very useful target insect for evaluation of endocrine disruptor chemicals (EDCs) due to mature breeding techniques, complete endocrine system and broad basic knowledge on developmental biology. Comparative metabolomics of silkworms with and without EDC exposure offers another dimension of studying EDCs. In this work, we report a workflow on metabolomic profiling of silkworm hemolymph based on high-performance chemical isotope labeling (CIL) liquid chromatography mass spectrometry (LC-MS) and demonstrate its application in studying the metabolic changes associated with the pesticide dichlorodiphenyltrichloroethane (DDT) exposure in silkworm. Hemolymph samples were taken from mature silkworms after growing on diet that contained DDT at four different concentrations (1, 0.1, 0.01, 0.001 ppm) as well as on diet without DDT as controls. They were subjected to differential 12 C-/ 13 C-dansyl labeling of the amine/phenol submetabolome, LC-UV quantification of the total amount of labeled metabolites for sample normalization, and LC-MS detection and relative quantification of individual metabolites in comparative samples. The total concentration of labeled metabolites did not show any significant change between four DDT-treatment groups and one control group. Multivariate statistical analysis of the metabolome data set showed that there was a distinct metabolomic separation between the five groups. Out of the 2044 detected peak pairs, 338 and 1471 metabolites have been putatively identified against the HMDB database and the EML library, respectively. 65 metabolites were identified by the dansyl library searching based on the accurate mass and retention time. Among the 65 identified metabolites, 33 positive metabolites had changes of greater than 1.20-fold or less than 0.83-fold in one or more groups with p-value of smaller than 0.05. Several useful biomarkers including serine, methionine, tryptophan, asymmetric dimethylarginine, N

Mechanical Properties of Transgenic Silkworm Silk Under High Strain Rate Tensile Loading

NASA Astrophysics Data System (ADS)

Chu, J.-M.; Claus, B.; Chen, W.

2017-12-01

Studies have shown that transgenic silkworm silk may be capable of having similar properties of spider silk while being mass-producible. In this research, the tensile stress-strain response of transgenic silkworm silk fiber is systematically characterized using a quasi-static load frame and a tension Kolsky bar over a range of strain-rates between 10^{-3} and 700/s. The results show that transgenic silkworm silk tends to have higher overall ultimate stress and failure strain at high strain rate (700/s) compared to quasi-static strain rates, indicating rate sensitivity of the material. The failure strain at the high strain rate is higher than that of spider silk. However, the stress levels are significantly below that of spider silk, and far below that of high-performance fiber. Failure surfaces are examined via scanning electron microscopy and reveal that the failure modes are similar to those of spider silk.

β-Fructofuranosidase Genes of the Silkworm, Bombyx mori

PubMed Central

Daimon, Takaaki; Taguchi, Tomohiro; Meng, Yan; Katsuma, Susumu; Mita, Kazuei; Shimada, Toru

2008-01-01

Mulberry latex contains extremely high concentrations of alkaloidal sugar mimic glycosidase inhibitors, such as 1,4-dideoxy-1,4-imino-d-arabinitol (d-AB1) and 1-deoxynojirimycin (DNJ). Although these compounds do not harm the silkworm, Bombyx mori, a mulberry specialist, they are highly toxic to insects that do not normally feed on mulberry leaves. d-AB1 and DNJ are strong inhibitors of α-glucosidases (EC 3.2.1.20); however, they do not affect the activity ofβ-fructofuranosidases (EC 3.2.1.26). Althoughα-glucosidase genes are found in a wide range of organisms, β-fructofuranosidase genes have not been identified in any animals so far. In this study, we report the identification and characterization of β-fructofuranosidase genes (BmSuc1 and BmSuc2) from B. mori. The BmSuc1 gene was highly expressed in the midgut and silk gland, whereas the expression of BmSuc2 gene was not detected. BmSuc1 encodes a functional β-fructofuranosidase, whose enzymatic activity was not inhibited by DNJ or d-AB1. We also showed that BmSUC1 protein localized within the midgut goblet cell cavities. Collectively, our data clearly demonstrated that BmSuc1 serves as a sugar-digesting enzyme in the silkworm physiology. This anomalous presence of the β-fructofuranosidase gene in the B. mori genome may partly explain why the silkworm can circumvent the mulberry's defense system. PMID:18397891

RNA-Seq Analyses for Two Silkworm Strains Reveals Insight into Their Susceptibility and Resistance to Beauveria bassiana Infection.

PubMed

Xing, Dongxu; Yang, Qiong; Jiang, Liang; Li, Qingrong; Xiao, Yang; Ye, Mingqiang; Xia, Qingyou

2017-02-10

The silkworm Bombyx mori is an economically important species. White muscardine caused by Beauveria bassiana is the main fungal disease in sericulture, and understanding the silkworm responses to B. bassiana infection is of particular interest. Herein, we investigated the molecular mechanisms underlying these responses in two silkworm strains Haoyue (HY, sensitive to B. bassiana ) and Kang 8 (K8, resistant to B. bassiana ) using an RNA-seq approach. For each strain, three biological replicates for immersion treatment, two replicates for injection treatment and three untreated controls were collected to generate 16 libraries for sequencing. Differentially expressed genes (DEGs) between treated samples and untreated controls, and between the two silkworm strains, were identified. DEGs and the enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways of the two strains exhibited an obvious difference. Several genes encoding cuticle proteins, serine proteinase inhibitors (SPI) and antimicrobial peptides (AMP) and the drug metabolism pathway involved in toxin detoxification were considered to be related to the resistance of K8 to B. bassiana. These results revealed insight into the resistance and susceptibility of two silkworm strains against B. bassiana infection and provided a roadmap for silkworm molecular breeding to enhance its resistance to B. bassiana .

RNA-Seq Analyses for Two Silkworm Strains Reveals Insight into Their Susceptibility and Resistance to Beauveria bassiana Infection

PubMed Central

Xing, Dongxu; Yang, Qiong; Jiang, Liang; Li, Qingrong; Xiao, Yang; Ye, Mingqiang; Xia, Qingyou

2017-01-01

The silkworm Bombyx mori is an economically important species. White muscardine caused by Beauveria bassiana is the main fungal disease in sericulture, and understanding the silkworm responses to B. bassiana infection is of particular interest. Herein, we investigated the molecular mechanisms underlying these responses in two silkworm strains Haoyue (HY, sensitive to B. bassiana) and Kang 8 (K8, resistant to B. bassiana) using an RNA-seq approach. For each strain, three biological replicates for immersion treatment, two replicates for injection treatment and three untreated controls were collected to generate 16 libraries for sequencing. Differentially expressed genes (DEGs) between treated samples and untreated controls, and between the two silkworm strains, were identified. DEGs and the enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways of the two strains exhibited an obvious difference. Several genes encoding cuticle proteins, serine proteinase inhibitors (SPI) and antimicrobial peptides (AMP) and the drug metabolism pathway involved in toxin detoxification were considered to be related to the resistance of K8 to B. bassiana. These results revealed insight into the resistance and susceptibility of two silkworm strains against B. bassiana infection and provided a roadmap for silkworm molecular breeding to enhance its resistance to B. bassiana. PMID:28208575

Alteration of a recombinant protein N-glycan structure in silkworms by partial suppression of N-acetylglucosaminidase gene expression.

PubMed

Kato, Tatsuya; Kikuta, Kotaro; Kanematsu, Ayumi; Kondo, Sachiko; Yagi, Hirokazu; Kato, Koichi; Park, Enoch Y

2017-09-01

To synthesize complex type N-glycans in silkworms, shRNAs against the fused lobe from Bombyx mori (BmFDL), which codes N-acetylglucosaminidase (GlcNAcase) in the Golgi, was expressed by recombinant B. mori nucleopolyhedrovirus (BmNPV) in silkworm larvae. Expression was under the control of the actin promoter of B. mori or the U6-2 and i.e.-2 promoters from Orgyia pseudotsugata multiple nucleopolyhedrovirus (OpMNPV). The reduction of specific GlcNAcase activity was observed in Bm5 cells and silkworm larvae using the U6-2 promoter. In silkworm larvae, the partial suppression of BmFDL gene expression was observed. When shRNA against BmFDL was expressed under the control of U6-2 promoter, the Man 3 GlcNAc(Fuc)GlcNAc structure appeared in a main N-glycans of recombinant human IgG. These results suggested that the control of BmFDL expression by its shRNA in silkworms caused the modification of its N-glycan synthetic pathway, which may lead to the alteration of N-glycans in the expressed recombinant proteins. Suppression of BmFDL gene expression by shRNA is not sufficient to synthesize complex N-glycans in silkworm larvae but can modify the N-glycan synthetic pathway.

A possible mechanism for low affinity of silkworm Na+/K+-ATPase for K.

PubMed

Homareda, Haruo; Otsu, Masahiro; Yamamoto, Sachiko; Ushimaru, Makoto; Ito, Sayaka; Fukutomi, Toshiyuki; Jo, Taeho; Eishi, Yoshinobu; Hara, Yukichi

2017-12-01

The affinity for K + of silkworm nerve Na + /K + -ATPase is markedly lower than that of mammalian Na + /K + -ATPase (Homareda 2010). In order to obtain clues on the molecular basis of the difference in K + affinities, we cloned cDNAs of silkworm (Bombyx mori) nerve Na + /K + -ATPase α and β subunits, and analyzed the deduced amino acid sequences. The molecular masses of the α and β subunits were presumed to be 111.5 kDa with ten transmembrane segments and 37.7 kDa with a single transmembrane segment, respectively. The α subunit showed 75% identity and 93% homology with the pig Na + /K + -ATPase α1 subunit. On the other hand, the amino acid identity of the β subunit with mammalian counterparts was as low as 30%. Cloned α and β cDNAs were co-expressed in cultured silkworm ovary-derived cells, BM-N cells, which lack endogenous Na + /K + -ATPase. Na + /K + -ATPase expressed in the cultured cells showed a low affinity for K + and a high affinity for Na + , characteristic of the silkworm nerve Na + /K + -ATPase. These results suggest that the β subunit is responsible for the affinity for K + of Na + /K + -ATPase.

Pharmacokinetic parameters explain the therapeutic activity of antimicrobial agents in a silkworm infection model.

PubMed

Paudel, Atmika; Panthee, Suresh; Urai, Makoto; Hamamoto, Hiroshi; Ohwada, Tomohiko; Sekimizu, Kazuhisa

2018-01-25

Poor pharmacokinetic parameters are a major reason for the lack of therapeutic activity of some drug candidates. Determining the pharmacokinetic parameters of drug candidates at an early stage of development requires an inexpensive animal model with few associated ethical issues. In this study, we used the silkworm infection model to perform structure-activity relationship studies of an antimicrobial agent, GPI0039, a novel nitrofuran dichloro-benzyl ester, and successfully identified compound 5, a nitrothiophene dichloro-benzyl ester, as a potent antimicrobial agent with superior therapeutic activity in the silkworm infection model. Further, we compared the pharmacokinetic parameters of compound 5 with a nitrothiophene benzyl ester lacking chlorine, compound 7, that exerted similar antimicrobial activity but had less therapeutic activity in silkworms, and examined the metabolism of these antimicrobial agents in human liver fractions in vitro. Compound 5 had appropriate pharmacokinetic parameters, such as an adequate half-life, slow clearance, large area under the curve, low volume of distribution, and long mean residence time, compared with compound 7, and was slowly metabolized by human liver fractions. These findings suggest that the therapeutic effectiveness of an antimicrobial agent in the silkworms reflects appropriate pharmacokinetic properties.

Toyama Kametaro and Vernon Kellogg: silkworm inheritance experiments in Japan, Siam, and the United States, 1900-1912.

PubMed

Onaga, Lisa

2010-01-01

Japanese agricultural scientist Toyama Kametaro's report about the Mendelian inheritance of silkworm cocoon color in Studies on the Hybridology of Insects (1906) spurred changes in Japanese silk production and thrust Toyama and his work into a scholarly exchange with American entomologist Vernon Kellogg. Toyama's work, based on research conducted in Japan and Siam, came under international scrutiny at a time when analyses of inheritance flourished after the "rediscovery" of Mendel's laws of heredity in 1900. The hybrid silkworm studies in Asia attracted the attention of Kellogg, who was concerned with how experimental biology would be used to study the causes of natural selection. He challenged Toyama's conclusions that Mendelism alone could explain the inheritance patterns of silkworm characters such as cocoon color because they had been subject to hundreds of years of artificial selection, or breeding. This examination of the intersection of Japanese sericulture and American entomology probes how practical differences in scientific interests, societal responsibilities, and silkworm materiality were negotiated throughout the processes of legitimating Mendelian genetics on opposite sides of the Pacific. The ways in which Toyama and Kellogg assigned importance to certain silkworm properties show how conflicting intellectual orientations arose in studies of the same organism. Contestation about Mendelism took place not just on a theoretical level, but the debate was fashioned through each scientist's rationale about the categorization of silkworm breeds and races and what counted as "natural". This further mediated the acceptability of the silkworm not as an experimental organism, but as an appropriately "natural" insect with which to demonstrate laws of inheritance. All these shed light on the challenges that came along with the use of agricultural animals to convincingly articulate new biological principles.

Evaluation of pathogenicity of Candida albicans in germination-ready states using a silkworm infection model.

PubMed

Matsumoto, Haruhito; Nagao, Jun-ichi; Cho, Tamaki; Kodama, Jun

2013-01-01

We previously developed an N-acetyl-D-glucosamine (GlcNAc) medium which induces Candida albicans to undergo a yeast-to-hyphal transition through a cAMP-PKA pathway. Microarray analysis demonstrated that 18 genes, including ALS3 that encodes a cell wall adhesion, were upregulated by 30-min incubation of yeast cells at 37°C in the GlcNAc medium. To investigate the differences between morphological transition and morphotype in C. albicans as a consequence of infection, this study utilized a silkworm infection model as an invertebrate mini-host. We prepared 3 different conditions of C. albicans cells in vitro by changing the incubation times in the GlcNAc medium: yeast-form cells at 0 min (Y0 cells), yeast-form cells in germination-ready state at 60 min (Y60 cells), and hyphal cells at 120 min (H120 cells), and compared their pathogenicities. We performed the infection study at various temperatures to find temperature-dependent virulence factors in vivo. Y60 cells in germination-ready state in the GlcNAc medium showed higher pathogenicity in vivo compared to Y0 and H120 cells at 30°C. Y60 cells proliferated in silkworms 24 h post-injection at 30°C, whereas the other 2 cell types did not. In vitro analysis demonstrated that Y60 cells, but not Y0 cells, germinated in the silkworm hemolymph at 30°C. However, Y0 and Y60 cells showed a similar degree of germination in the silkworm hemolymph at 37°C, although no significant difference in silkworm survival after infection with each cell type was observed at 37°C. These results suggested that the germination-ready state induced by the GlcNAc medium contributed to virulence in the silkworm.

High-Toughness Silk Produced by a Transgenic Silkworm Expressing Spider (Araneus ventricosus) Dragline Silk Protein

PubMed Central

Kuwana, Yoshihiko; Sezutsu, Hideki; Nakajima, Ken-ichi; Tamada, Yasushi; Kojima, Katsura

2014-01-01

Spider dragline silk is a natural fiber that has excellent tensile properties; however, it is difficult to produce artificially as a long, strong fiber. Here, the spider (Araneus ventricosus) dragline protein gene was cloned and a transgenic silkworm was generated, that expressed the fusion protein of the fibroin heavy chain and spider dragline protein in cocoon silk. The spider silk protein content ranged from 0.37 to 0.61% w/w (1.4–2.4 mol%) native silkworm fibroin. Using a good silk-producing strain, C515, as the transgenic silkworm can make the raw silk from its cocoons for the first time. The tensile characteristics (toughness) of the raw silk improved by 53% after the introduction of spider dragline silk protein; the improvement depended on the quantity of the expressed spider dragline protein. To demonstrate the commercial feasibility for machine reeling, weaving, and sewing, we used the transgenic spider silk to weave a vest and scarf; this was the first application of spider silk fibers from transgenic silkworms. PMID:25162624

High-toughness silk produced by a transgenic silkworm expressing spider (Araneus ventricosus) dragline silk protein.

PubMed

Kuwana, Yoshihiko; Sezutsu, Hideki; Nakajima, Ken-ichi; Tamada, Yasushi; Kojima, Katsura

2014-01-01

Spider dragline silk is a natural fiber that has excellent tensile properties; however, it is difficult to produce artificially as a long, strong fiber. Here, the spider (Araneus ventricosus) dragline protein gene was cloned and a transgenic silkworm was generated, that expressed the fusion protein of the fibroin heavy chain and spider dragline protein in cocoon silk. The spider silk protein content ranged from 0.37 to 0.61% w/w (1.4-2.4 mol%) native silkworm fibroin. Using a good silk-producing strain, C515, as the transgenic silkworm can make the raw silk from its cocoons for the first time. The tensile characteristics (toughness) of the raw silk improved by 53% after the introduction of spider dragline silk protein; the improvement depended on the quantity of the expressed spider dragline protein. To demonstrate the commercial feasibility for machine reeling, weaving, and sewing, we used the transgenic spider silk to weave a vest and scarf; this was the first application of spider silk fibers from transgenic silkworms.

From silkworms to bees: Diseases of beneficial insects

USDA-ARS?s Scientific Manuscript database

The diseases of the silkworm (Bombyx mori) and managed bees, including the honey bee (Apis mellifera), bumbles bees (Bombus spp.), the alfalfa leafcutting bee (Megachile rotundata), and mason bees (Osmia spp.) are reviewed, with diagnostic descriptions and a summary of control methods for production...

Polyhydroxylated alkaloids isolated from mulberry trees (Morusalba L.) and silkworms (Bombyx mori L.).

PubMed

Asano, N; Yamashita, T; Yasuda, K; Ikeda, K; Kizu, H; Kameda, Y; Kato, A; Nash, R J; Lee, H S; Ryu, K S

2001-09-01

New polyhydroxylated alkaloids, (2R,3R,4R)-2-hydroxymethyl-3,4-dihydroxypyrrolidine-N-propionamide from the root bark of Morus alba L., and 4-O-alpha-D-galactopyranosyl-calystegine B(2) and 3 beta,6 beta-dihydroxynortropane from the fruits, were isolated by column chromatography using a variety of ion-exchange resins. Fifteen other polyhydroxylated alkaloids were also isolated. 1-Deoxynojirimycin, a potent alpha-glucosidase inhibitor, was concentrated 2.7-fold by silkworms feeding on mulberry leaves. Some alkaloids contained in mulberry leaves were potent inhibitors of mammalian digestive glycosidases but not inhibitors of silkworm midgut glycosidases, suggesting that the silkworm has enzymes specially adapted to enable it to feed on mulberry leaves. The possibility of preventing the onset of diabetes and obesity using natural dietary supplements containing 1-deoxynojirimycin and other alpha-glucosidase inhibitors in high concentration is of great potential interest.

Intestinal microecology associated with fluoride resistance capability of the silkworm (Bombyx mori L.).

PubMed

Li, Guan-Nan; Xia, Xue-Juan; Tang, Wen-Chao; Zhu, Yong

2016-08-01

The silkworm (Bombyx mori L.) is an ideal model of Lepidoptera. However, the diversity and function of the intestinal microbiota in the gut of silkworm remain largely unknown. Changes in the intestinal microecology in fluoride-resistant strain T6 and fluoride-susceptible strain 734 of the silkworm in response to fluoride exposure were investigated. T6 and 734 were treated with 200 mg/kg fluoride (designated as T6-T and 734-T groups) and deionized water (designated as T6-C and 734-C groups). Culture-dependent approach revealed that the numbers of intestinal bacteria in the 734-T group significantly decreased compared with that in the 734-C group (4.8 ± 0.6 × 10(7) CFU/mL vs. 7.5 ± 0.7 × 10(7) CFU/mL; P < 0.05). Analyses of the intestinal content pH showed that the pH decreased in the 734-T group only. Additionally, SCFA concentrations significantly decreased in both treatment groups compared with the control groups. High-throughput sequencing indicated that the intestinal microbiota in the 734-T group was significantly more diverse than those in the other groups. The bacterial community was composed of two dominant groups (Firmicutes and Proteobacteria). Principal component analyses revealed a significant difference in the composition of the intestinal microbiota in the 734-T group compared with those in the other groups. Thaumarchaeota and Euryarchaeota were more abundant in the 734-T group, but they were less abundant in the other groups. This study enhances our understanding about the diversity and function of silkworm intestinal microbiota in response to fluoride exposure among silkworm strains with diverse resistance.

Oak Decline

Treesearch

Philip M. Wargo; David R. Houston; Leon A. LaMadeleine

1983-01-01

Periodic occurrences of decline and death of oaks over widespread areas have been recorded since 1900. These outbreaks, variously named oak decline, oak dieback, or oak mortality, are caused by a complex interaction of environmental stresses and pests and given the name oak decline.

Development of Novel Antibiotic Lysocin E Identified by Silkworm Infection Model.

PubMed

Hamamoto, Hiroshi; Sekimizu, Kazuhisa

2017-01-01

In this symposium, we reported the identification and mechanistic analysis of a novel antibiotic named lysocin E. Lysocin E was identified by screening for therapeutic effectiveness in a silkworm Staphylococcus aureus infection model. The advantages of the silkworm infection model for screening and purification of antibiotics from the culture supernatant of soil bacteria are: 1) low cost; 2) no ethical issues; 3) convenient for evaluation of the therapeutic effectiveness of antibiotics; and 4) pharmacokinetics similar to those of mammals. Lysocin E has remarkable features compared with known antibiotics such as a novel mechanism of action and target. Here, we summarize our reports presented in this symposium.

Comparative proteomic analysis between the domesticated silkworm (Bombyx mori) reared on fresh mulberry leaves and on artificial diet.

PubMed

Zhou, Zhong-Hua; Yang, Hui-Juan; Chen, Ming; Lou, Cheng-Fu; Zhang, Yao-Zhou; Chen, Ke-Ping; Wang, Yong; Yu, Mei-Lan; Yu, Fang; Li, Jian-Ying; Zhong, Bo-Xiong

2008-12-01

To gain an insight into the effects of different diets on growth and development of the domesticated silkworm at protein level, we employed comparative proteomic approach to investigate the proteomic differences of midgut, hemolymph, fat body and posterior silk gland of the silkworms reared on fresh mulberry leaves and on artificial diet. Seventy-six differentially expressed proteins were identified by MALDI TOF/TOF MS, and among them, 41 proteins were up-regulated, and 35 proteins were downregulated. Database searches, combined with GO analysis and KEGG pathway analysis revealed that some hemolymph proteins such as Nuecin, Gloverin-like proteins, PGRP, P50 and beta/-N-acetylglucosamidase were related to innate immunity of the silkworm, and some proteins identified in silkworm midgut including Myosin 1 light chain, Tropomyosin 1, Profilin, Serpin-2 and GSH-Px were involved in digestion and nutrition absorption. Moreover, two up-regulated enzymes in fat body of larvae reared on artificial diet were identified as V-ATPase subunit B and Arginine kinase which participate in energy metabolism. Furthermore, 6 down-regulated proteins identified in posterior silk gland of silkworm larvae reared on artificial diet including Ribosomal protein SA, EF-2, EF-1gamma, AspAT, ERp57 and PHB were related to silk synthesis. Our results suggested that the different diets could alter the expression of proteins related to immune system, digestion and absorption of nutrient, energy metabolism and silk synthesis poor nutrition and absorption of nutrition in silkworm. The results also confirmed that the poor nutrient absorption, weakened innate immunity, decreased energy metabolism and reduced silk synthesis are the main reasons for low cocoons yield, inferior filament quality, low survival rate of young larvae and insufficient resistance against specific pathogens in the silkworms fed on artificial diet.

Identification and methods for prevention of Enterococcus mundtii infection in silkworm larvae, Bombyx mori, reared on artificial diet.

PubMed

Nwibo, Don Daniel; Matsumoto, Yasuhiko; Sekimizu, Kazuhisa

2015-06-01

Previously, it was reported that Enterococcus mundtii (E. mundtii) was associated with flacherie disease of silkworm larvae reared on artificial diet. In this study, we report that E. mundtii was isolated from diseased silkworm larvae, and validated as a pathogenic bacterium of the animal. When silkworm larva was infected with 1.04 × 10⁶ colony-forming units of E. mundtii via oral administration of diet, half population died within six days, indicating that the bacterium is pathogenic to silkworm. Less severe infection was found to cause anorexia and hamper the development of larvae. This pathogen was found to proliferate in both time- and dose-dependent manner in the gastrointestinal tract of the animal. The bacterium was isolated from powder of artificial diet made from mulberry leaves, and from mulberry leaves growing at a field. Minimum inhibitory concentration determination revealed that this bacterium was susceptible to tested antibiotics. Vancomycin treatment of diet significantly decreased the number of E. mundtii in intestine of silkworm larvae infected with the bacteria, compared to control. Furthermore, autoclaving or gamma ray irradiation of diet was also effective for exclusion of E. mundtii from the diet without the loss of its nutrient capacities. These results suggest that mulberry leaves used in making artificial diet for silkworm larvae is one of the sources of E. mundtii infection; and that antibiotic treatment, autoclaving or gamma ray irradiation of artificial diet can exclude the bacteria.

Mineralization and biocompatibility of Antheraea pernyi (A. pernyi) silk sericin film for potential bone tissue engineering.

PubMed

Yang, Mingying; Mandal, Namita; Shuai, Yajun; Zhou, Guanshan; Min, Sijia; Zhu, Liangjun

2014-01-01

This study aimed to investigate the mineralization of Antheraea pernyi (A. pernyi) silk sericin. Mineralization of A. pernyi sericin was performed by alternative soaking in calcium and phosphate. The inhibition of precipitation of calcium carbonate and von Kossa staining on A. pernyi sericin were tested, and the corresponding results prove that A. pernyi sericin has Ca binding activity. Scanning electron microscope (SEM) observation shows that spherical crystals could be nucleated on the A. pernyi sericin film. These crystals were confirmed to be hydroxyapatite according to FT-IR and XRD spectra, indicating that A. pernyi sericin is capable of mineralization. In addition, cell adhesion and growth activity assay demonstrate that A. pernyi sericin shows excellent biocompatibility for the growth of MG-63 cells.

Silkworm Sericin: Properties and Biomedical Applications.

PubMed

Kunz, Regina Inês; Brancalhão, Rose Meire Costa; Ribeiro, Lucinéia de Fátima Chasko; Natali, Maria Raquel Marçal

2016-01-01

Silk sericin is a natural polymer produced by silkworm, Bombyx mori , which surrounds and keeps together two fibroin filaments in silk thread used in the cocoon. The recovery and reuse of sericin usually discarded by the textile industry not only minimizes environmental issues but also has a high scientific and commercial value. The physicochemical properties of the molecule are responsible for numerous applications in biomedicine and are influenced by the extraction method and silkworm lineage, which can lead to variations in molecular weight and amino acid concentration of sericin. The presence of highly hydrophobic amino acids and its antioxidant potential make it possible for sericin to be applied in the food and cosmetic industry. The moisturizing power allows indications as a therapeutic agent for wound healing, stimulating cell proliferation, protection against ultraviolet radiation, and formulating creams and shampoos. The antioxidant activity associated with low digestibility of sericin that expands the application in the medical field, such as antitumour, antimicrobial and anti-inflammatory agent, anticoagulant, acts in colon health, improving constipation and protects the body from obesity through improved plasma lipid profile. In addition, the properties of sericin allow its application as a culture medium and cryopreservation, in tissue engineering and for drug delivery, demonstrating its effective use, as an important biomaterial.

Silkworm Sericin: Properties and Biomedical Applications

PubMed Central

Ribeiro, Lucinéia de Fátima Chasko

2016-01-01

Silk sericin is a natural polymer produced by silkworm, Bombyx mori, which surrounds and keeps together two fibroin filaments in silk thread used in the cocoon. The recovery and reuse of sericin usually discarded by the textile industry not only minimizes environmental issues but also has a high scientific and commercial value. The physicochemical properties of the molecule are responsible for numerous applications in biomedicine and are influenced by the extraction method and silkworm lineage, which can lead to variations in molecular weight and amino acid concentration of sericin. The presence of highly hydrophobic amino acids and its antioxidant potential make it possible for sericin to be applied in the food and cosmetic industry. The moisturizing power allows indications as a therapeutic agent for wound healing, stimulating cell proliferation, protection against ultraviolet radiation, and formulating creams and shampoos. The antioxidant activity associated with low digestibility of sericin that expands the application in the medical field, such as antitumour, antimicrobial and anti-inflammatory agent, anticoagulant, acts in colon health, improving constipation and protects the body from obesity through improved plasma lipid profile. In addition, the properties of sericin allow its application as a culture medium and cryopreservation, in tissue engineering and for drug delivery, demonstrating its effective use, as an important biomaterial. PMID:27965981

A new arylalkylamine N-acetyltransferase in silkworm (Bombyx mori) affects integument pigmentation.

PubMed

Long, Yaohang; Li, Jiaorong; Zhao, Tianfu; Li, Guannan; Zhu, Yong

2015-04-01

Dopamine is a precursor for melanin synthesis. Arylalkylamine N-acetyltransferase (AANAT) is involved in the melatonin formation in insects because it could catalyze the transformation from dopamine to dopamine-N-acetyldopamine. In this study, we identified a new AANAT gene in the silkworm (Bombyx mori) and assessed its role in the silkworm. The cDNA of this gene encodes 233 amino acids that shares 57 % amino acid identity with the Bm-iAANAT protein. We thus refer to this gene as Bm-iAANAT2. To investigate the role of Bm-iAANAT2, we constructed a transgenic interference system using a 3xp3 promoter to suppress the expression of Bm-iAANAT2 in the silkworm. We observed that melanin deposition occurs in the head and integument in transgenic lines. To verify the melanism pattern, dopamine content and the enzyme activity of AANAT were determined by high-performance liquid chromatography (HPLC). We found that an increase in dopamine levels affects melanism patterns on the heads of transgenic B. mori. A reduction in the enzyme activity of AANAT leads to changes in dopamine levels. We analyzed the expression of the Bm-iAANAT2 genes by qPCR and found that the expression of Bm-iAANAT2 gene is significantly lower in transgenic lines. Our results lead us to conclude that Bm-iAANAT2 is a new arylalkylamine N-acetyltransferase gene in the silkworm and is involved in the metabolism of the dopamine to avoid the generation of melanin.

Female qualities in males: vitellogenin synthesis induced by ovary transplants into the male silkworm, Bombyx mori.

PubMed

Yang, Congwen; Lin, Ying; Shen, Guanwang; Chen, Enxiang; Wang, Yanxia; Luo, Juan; Zhang, Haiyan; Xing, Runmiao; Xia, Qingyou

2014-10-10

Female qualities in males are common in vertebrates but have not been extensively reported in insects. Vitellogenin (Vg) is highly expressed in the female fat body and is generally required for the formation of yolk proteins in the insect egg. Vg upregulation is generally regarded as a female quality in female oviparous animals. In this study, we found that Bombyx mori Vg (BmVg) is especially highly expressed in the female pupa. Downregulation of the BmVg gene in the female pupa by RNA interference (RNAi) interfered with egg formation and embryonic development, showing the importance of BmVg in these processes. So, we used BmVg as a biomarker for female qualities in the silkworm. Hematoxylin-eosin staining and immunofluorescence histochemistry showed that ovary transplants induced BmVg synthesis in the male pupa fat body. Ovaries transplanted into male silkworms produced only a few eggs with deformed yolk granules. These results suggested that the amount of BmVg in the male silkworm was insufficient for eggs to undergo complete embryonic development. After 17-beta-estradiol was used to treat male pupae and male pupal fat bodies, BmVg was upregulated in vivo and in vitro. These findings indicated that the male silkworm has innate female qualities that were induced by a transplanted ovary and 17β-estradiol. However, in silkworms, female qualities in males are not as complete as in females. Copyright © 2014 Elsevier Inc. All rights reserved.

Characterization of the complete mitochondrial genome of the giant silkworm moth, Eriogyna pyretorum (Lepidoptera: Saturniidae).

PubMed

Jiang, Shao-Tong; Hong, Gui-Yun; Yu, Miao; Li, Na; Yang, Ying; Liu, Yan-Qun; Wei, Zhao-Jun

2009-05-22

The complete mitochondrial genome (mitogenome) of Eriogyna pyretorum (Lepidoptera: Saturniidae) was determined as being composed of 15,327 base pairs (bp), including 13 protein-coding genes (PCGs), 2 rRNA genes, 22 tRNA genes, and a control region. The arrangement of the PCGs is the same as that found in the other sequenced lepidopteran. The AT skewness for the E. pyretorum mitogenome is slightly negative (-0.031), indicating the occurrence of more Ts than As. The nucleotide composition of the E. pyretorum mitogenome is also biased toward A + T nucleotides (80.82%). All PCGs are initiated by ATN codons, except for cytochrome c oxidase subunit 1 and 2 (cox1 and cox2). Two of the 13 PCGs harbor the incomplete termination codon by T. All tRNA genes have a typical clover-leaf structure of mitochondrial tRNA, with the exception of trnS1(AGN) and trnS2(UCN). Phylogenetic analysis among the available lepidopteran species supports the current morphology-based hypothesis that Bombycoidea, Geometroidea, Notodontidea, Papilionoidea and Pyraloidea are monophyletic. As has been previously suggested, Bombycidae (Bombyx mori and Bombyx mandarina), Sphingoidae (Manduca sexta) and Saturniidae (Antheraea pernyi, Antheraea yamamai, E. pyretorum and Caligula boisduvalii) formed a group.

Characterization of the complete mitochondrial genome of the giant silkworm moth, Eriogyna pyretorum (Lepidoptera: Saturniidae)

PubMed Central

Jiang, Shao-Tong; Hong, Gui-Yun; Yu, Miao; Li, Na; Yang, Ying; Liu, Yan-Qun; Wei, Zhao-Jun

2009-01-01

The complete mitochondrial genome (mitogenome) of Eriogyna pyretorum (Lepidoptera: Saturniidae) was determined as being composed of 15,327 base pairs (bp), including 13 protein-coding genes (PCGs), 2 rRNA genes, 22 tRNA genes, and a control region. The arrangement of the PCGs is the same as that found in the other sequenced lepidopteran. The AT skewness for the E. pyretorum mitogenome is slightly negative (-0.031), indicating the occurrence of more Ts than As. The nucleotide composition of the E. pyretorum mitogenome is also biased toward A + T nucleotides (80.82%). All PCGs are initiated by ATN codons, except for cytochrome c oxidase subunit 1 and 2 (cox1 and cox2). Two of the 13 PCGs harbor the incomplete termination codon by T. All tRNA genes have a typical clover-leaf structure of mitochondrial tRNA, with the exception of trnS1(AGN) and trnS2(UCN). Phylogenetic analysis among the available lepidopteran species supports the current morphology-based hypothesis that Bombycoidea, Geometroidea, Notodontidea, Papilionoidea and Pyraloidea are monophyletic. As has been previously suggested, Bombycidae (Bombyx mori and Bombyx mandarina), Sphingoidae (Manduca sexta) and Saturniidae (Antheraea pernyi, Antheraea yamamai, E. pyretorum and Caligula boisduvalii) formed a group. PMID:19471586

Transcriptional profiling of midgut immunity response and degeneration in the wandering silkworm, Bombyx mori.

PubMed

Xu, Qiuyun; Lu, Anrui; Xiao, Guohua; Yang, Bing; Zhang, Jie; Li, Xuquan; Guan, Jingmin; Shao, Qimiao; Beerntsen, Brenda T; Zhang, Peng; Wang, Chengshu; Ling, Erjun

2012-01-01

Lepidoptera insects have a novel development process comprising several metamorphic stages during their life cycle compared with vertebrate animals. Unlike most Lepidoptera insects that live on nectar during the adult stage, the Bombyx mori silkworm adults do not eat anything and die after egg-laying. In addition, the midguts of Lepidoptera insects produce antimicrobial proteins during the wandering stage when the larval tissues undergo numerous changes. The exact mechanisms responsible for these phenomena remain unclear. We used the silkworm as a model and performed genome-wide transcriptional profiling of the midgut between the feeding stage and the wandering stage. Many genes concerned with metabolism, digestion, and ion and small molecule transportation were down-regulated during the wandering stage, indicating that the wandering stage midgut loses its normal functions. Microarray profiling, qRT-PCR and western blot proved the production of antimicrobial proteins (peptides) in the midgut during the wandering stage. Different genes of the immune deficiency (Imd) pathway were up-regulated during the wandering stage. However, some key genes belonging to the Toll pathway showed no change in their transcription levels. Unlike butterfly (Pachliopta aristolochiae), the midgut of silkworm moth has a layer of cells, indicating that the development of midgut since the wandering stage is not usual. Cell division in the midgut was observed only for a short time during the wandering stage. However, there was extensive cell apoptosis before pupation. The imbalance of cell division and apoptosis probably drives the continuous degeneration of the midgut in the silkworm since the wandering stage. This study provided an insight into the mechanism of the degeneration of the silkworm midgut and the production of innate immunity-related proteins during the wandering stage. The imbalance of cell division and apoptosis induces irreversible degeneration of the midgut. The Imd pathway

Developmental Changes for the Hemolymph Metabolome of Silkworm (Bombyx moriL.)

PubMed Central

Zhou, Lihong; Li, Huihui; Hao, Fuhua; Li, Ning; Liu, Xin; Wang, Guoliang; Wang, Yulan; Tang, Huiru

2015-01-01

Silkworm (Bombyx mori) is a lepidopteran-holometabolic model organism. To understand its developmental biochemistry, we characterized the larval hemolymph metabonome from the third instar to prepupa stage using 1H NMR spectroscopy whilst hemolymph fatty acid composition using GC-FID/MS. We unambiguously assigned more than 60 metabolites, among which tyrosine-o-β-glucuronide, mesaconate, homocarnosine, and picolinate were reported for the first time from the silkworm hemolymph. Phosphorylcholine was the most abundant metabolite in all developmental stages with exception for the periods before the third and fourth molting. We also found obvious developmental dependence for the hemolymph metabonome involving multiple pathways including protein biosyntheses, glycolysis, TCA cycle, the metabolisms of choline amino acids, fatty acids, purines, and pyrimidines. Most hemolymph amino acids had two elevations during the feeding period of the fourth instar and prepupa stage. Trehalose was the major blood sugar before day 8 of the fifth instar, whereas glucose became the major blood sugar after spinning. C16:0, C18:0 and its unsaturated forms were dominant fatty acids in hemolymph. The developmental changes of hemolymph metabonome were associated with dietary nutrient intakes, biosyntheses of cell membrane, pigments, proteins, and energy metabolism. These findings offered essential biochemistry information in terms of the dynamic metabolic changes during silkworm development. PMID:25825269

Developmental Changes for the Hemolymph Metabolome of Silkworm (Bombyx mori L.).

PubMed

Zhou, Lihong; Li, Huihui; Hao, Fuhua; Li, Ning; Liu, Xin; Wang, Guoliang; Wang, Yulan; Tang, Huiru

2015-05-01

Silkworm (Bombyx mori) is a lepidopteran-holometabolic model organism. To understand its developmental biochemistry, we characterized the larval hemolymph metabonome from the third instar to prepupa stage using (1)H NMR spectroscopy whilst hemolymph fatty acid composition using GC-FID/MS. We unambiguously assigned more than 60 metabolites, among which tyrosine-o-β-glucuronide, mesaconate, homocarnosine, and picolinate were reported for the first time from the silkworm hemolymph. Phosphorylcholine was the most abundant metabolite in all developmental stages with exception for the periods before the third and fourth molting. We also found obvious developmental dependence for the hemolymph metabonome involving multiple pathways including protein biosyntheses, glycolysis, TCA cycle, the metabolisms of choline amino acids, fatty acids, purines, and pyrimidines. Most hemolymph amino acids had two elevations during the feeding period of the fourth instar and prepupa stage. Trehalose was the major blood sugar before day 8 of the fifth instar, whereas glucose became the major blood sugar after spinning. C16:0, C18:0 and its unsaturated forms were dominant fatty acids in hemolymph. The developmental changes of hemolymph metabonome were associated with dietary nutrient intakes, biosyntheses of cell membrane, pigments, proteins, and energy metabolism. These findings offered essential biochemistry information in terms of the dynamic metabolic changes during silkworm development.

Oak wilt

Treesearch

Robert, Jr. Lewis

1989-01-01

Oak wilt, a major disease of oak trees in North America, is caused by a fungus. It infects the sapwood and stops sap flow to the branches, twigs, and leaves. When sap flow is restricted during the growing season, trees wilt and soon die. In addition to killing trees, oak wilt makes it more difficult to export oak logs to other countries. Logs must be free of oak wilt...

Sterol composition in larvae of the silkworm, Bombyx mori.

PubMed

Nagata, Shinji; Nagasawa, Hiromichi

2011-01-01

Sterols in silkworm larvae were analyzed. Cholesterol was predominantly detected in all tissues examined. Dietary phytosterols and desmosterol, a putative biosynthetic intermediate from phytosterols to cholesterol, were also detected, indicating that imperfect intestinal conversion from phytosterols to cholesterol influences the sterol composition in larval tissues.

Large-scale production of bioactive recombinant human acidic fibroblast growth factor in transgenic silkworm cocoons

NASA Astrophysics Data System (ADS)

Wang, Feng; Wang, Riyuan; Wang, Yuancheng; Zhao, Ping; Xia, Qingyou

2015-11-01

With an increasing clinical demand for functional therapeutic proteins every year, there is an increasing requirement for the massive production of bioactive recombinant human acidic fibroblast growth factor (r-haFGF). In this present study, we delicately explore a strategy for the mass production of r-haFGF protein with biological activity in the transgenic silkworm cocoons. The sequence-optimized haFGF was inserted into an enhanced sericin-1 expression system to generate the original transgenic silkworm strain, which was then further crossed with a PIG jumpstarter strain to achieve the remobilization of the expression cassette to a “safe harbor” locus in the genome for the efficient expression of r-haFGF. In consequence, the expression of r-haFGF protein in the mutant line achieved a 5.6-fold increase compared to the original strain. The high content of r-haFGF facilitated its purification and large-scald yields. Furthermore, the r-haFGF protein bioactively promoted the growth, proliferation and migration of NIH/3T3 cells, suggesting the r-haFGF protein possessed native mitogenic activity and the potential for wound healing. These results show that the silk gland of silkworm could be an efficient bioreactor strategy for recombinant production of bioactive haFGF in silkworm cocoons.

Indigenous Indonesian Wild Silkworm Cocoon of Attacus atlas as Biocompatible Film Biomaterial

NASA Astrophysics Data System (ADS)

Nindhia, T. G. T.; Knejzlik, Z.; Ruml, T.; Surata, I. W.; Nindhia, T. S.

2017-05-01

The biocompatible film made from wild silkworm cocoon of Attacus atlas is intorduced in this research for anticipation of demand on biocompatible film for regenerative medicine. The wild silkworm cocoon was indigenous Indonesia and was taken from it original location in Indonesia. Protocol for degumming method was obtained in this research by using treatment with NaOH solution at 0.1 M for 1 hour. The film was prepared by grinding the wet degummed fiber until pulp like state was obtained. The mixture was dropped in sequence on the hot ceramic plate with temperature around 60°C. The film thickness can be controlled precisely by using this technique. The film is soaked in alcohor for 1 day for stability testing and the result is found stable. The film is introduced in to COS-1 Cell suspension with previously washed in PBS solution and put in a chamber for biocompatibility testing. The cell are found able to grow and attach in first day observation and dramatically increase after 3 days observation. This is an indicate that the film that is produced from wild silkworm cocon of Attacus atlas has excellent biocompatibility.

Purification and Functional Characterization of a Protein: Bombyx mori Human Growth Hormone Like Protein in Silkworm Pupa

PubMed Central

Lv, Zhengbing; Nie, Zuoming; Chen, Jian; Chen, Hao; Yu, Wei; Gai, Qijing; Zhang, Yaozhou

2014-01-01

Human growth hormone (hGH) is a peptide hormone secreted by eosinophils of the human anterior pituitary, and a regulatory factor for a variety of metabolic pathways. A 30-kD protein from the pupa stage of silkworm was detected by Western blotting and confirmed by immunoprecipitation based on its ability to bind to anti-hGH antibody. This protein, named BmhGH-like protein, was purified from fresh silkworm pupas through low-temperature homogenization, filtration, and centrifugation to remove large impurity particles. The supernatants were precipitated, resuspended, and passed through a molecular sieve. Further purification by affinity chromatography and two-dimensional electrophoresis resulted in pure protein for analysis by MS MALDI-TOF-MS analysis. An alignment with predicted proteins indicated that BmhGH-like protein consisted of two lipoproteins, which we named hGH-L1 and hGH-L2. These proteins belong to the β-trefoil superfamily, with β domains similar to the spatial structure of hGH. Assays with K562 cells demonstrated that these proteins could promote cell division in vitro. To further validate the growth-promoting effects, hGH-L2 was cloned from pupa cDNA to create recombinant silkworm baculovirus vBmNPV-hGH-L2, which was used to infect silkworm BmN cells at low titer. Flow cytometric analysis demonstrated that the protein shortened the G0/G1 phase of the cells, and enabled the cells to rapidly traverse the G1/S phase transition point to enter S phase and promote cell division. Discovery of hGH-like protein in silkworm will once again arouse people’s interest in the potential medicinal value of silkworm and establish the basis for the development of new hormone drugs. PMID:25469649

Purification and functional characterization of a protein: Bombyx mori human growth hormone like protein in silkworm pupa.

PubMed

Chen, Jianqing; Shu, Tejun; Lv, Zhengbing; Nie, Zuoming; Chen, Jian; Chen, Hao; Yu, Wei; Gai, Qijing; Zhang, Yaozhou

2014-01-01

Human growth hormone (hGH) is a peptide hormone secreted by eosinophils of the human anterior pituitary, and a regulatory factor for a variety of metabolic pathways. A 30-kD protein from the pupa stage of silkworm was detected by Western blotting and confirmed by immunoprecipitation based on its ability to bind to anti-hGH antibody. This protein, named BmhGH-like protein, was purified from fresh silkworm pupas through low-temperature homogenization, filtration, and centrifugation to remove large impurity particles. The supernatants were precipitated, resuspended, and passed through a molecular sieve. Further purification by affinity chromatography and two-dimensional electrophoresis resulted in pure protein for analysis by MS MALDI-TOF-MS analysis. An alignment with predicted proteins indicated that BmhGH-like protein consisted of two lipoproteins, which we named hGH-L1 and hGH-L2. These proteins belong to the β-trefoil superfamily, with β domains similar to the spatial structure of hGH. Assays with K562 cells demonstrated that these proteins could promote cell division in vitro. To further validate the growth-promoting effects, hGH-L2 was cloned from pupa cDNA to create recombinant silkworm baculovirus vBmNPV-hGH-L2, which was used to infect silkworm BmN cells at low titer. Flow cytometric analysis demonstrated that the protein shortened the G0/G1 phase of the cells, and enabled the cells to rapidly traverse the G1/S phase transition point to enter S phase and promote cell division. Discovery of hGH-like protein in silkworm will once again arouse people's interest in the potential medicinal value of silkworm and establish the basis for the development of new hormone drugs.

Identification of a Serratia marcescens virulence factor that promotes hemolymph bleeding in the silkworm, Bombyx mori.

PubMed

Ishii, Kenichi; Adachi, Tatsuo; Hara, Takashi; Hamamoto, Hiroshi; Sekimizu, Kazuhisa

2014-03-01

Injection of culture supernatant of Serratia marcescens, a Gram-negative bacterium pathogenic to a wide range of host animals including insects and mammals, into the hemolymph of silkworm (Bombyx mori) larvae led to continuous flow of the hemolymph (blood of insects) from the injection site. The amount of hemolymph lost within 60 min reached 15-20% of the total larval weight. Using a bioassay with live silkworms, we purified Serralysin, a metalloprotease that requires divalent cations for its activity, as the factor responsible for the promotion of hemolymph bleeding from the culture supernatant of S. marcescens. Recombinant protein also induced hemolymph bleeding in silkworms. Moreover, the culture supernatant of an S. marcescens disruption mutant of the ser gene showed attenuated ability to promote hemolymph bleeding. In addition, this bleeding-promoting activity of the S. marcescens culture supernatant was attenuated by disruption of the wecA gene, which is involved in the biosynthesis of the lipopolysaccharide O-antigen. These findings suggest that Serralysin metalloprotease contributes to the pathogenesis of S. marcescens by inhibiting wound healing, which leads to a massive loss of hemolymph from silkworm larvae. Copyright © 2014 Elsevier Inc. All rights reserved.

Photosensitivity in the circadian hatching rhythm of the carotenoid-depleted silkworm, Bombyx mori.

PubMed

Sakamoto, K; Shimizu, I

1994-01-01

Silkworms (Bombyx mori) were reared on a carotenoid-deprived artificial diet, and the carotenoid-depleted eggs of the next generation were incubated so that we could observe the effect of the depletion on the circadian rhythm of hatching. The phototactic response curves of newly hatched larvae showed that the visual photosensitivity in ocelli of larvae from the carotenoid-depleted eggs was at least 4 log units lower than that of a carotenoid-rich control group. However, the phase-shift experiment revealed that carotenoid depletion did not reduce the photosensitivity in the hatching rhythm. When the hatching rhythm was generated by exposure to a single light pulse in constant darkness, the first peak in the rhythm of the carotenoid-depleted silkworms occurred significantly earlier than that of the carotenoid-rich group, but the following second peaks of both groups were found at the same time. These results suggest that for the silkworm, carotenoid is not involved in photoreception for the hatching rhythm, but is involved in the timing of hatching.

Effect of Venom from the Jellyfish Nemopilema nomurai on the Silkworm Bombyx mori L.

PubMed

Yu, Huahua; Li, Rongfeng; Chen, Xiaolin; Yue, Yang; Xing, Ronge; Liu, Song; Li, Pengcheng

2015-09-24

The silkworm Bombyx mori L. (B. mori) has a significant impact on the economy by producing more than 80% of the globally produced raw silk. The exposure of silkworm to pesticides may cause adverse effects on B. mori, such as a reduction in the production and quality of silk. This study aims to assay the effect of venom from the jellyfish Nemopilema nomurai on growth, cuticle and acetylcholinesterase (AChE) activity of the silkworm B. mori by the leaf dipping method. The experimental results revealed that the four samples caused neither antifeeding nor a lethal effect on B. mori. The sample SFV inhibited B. mori growth after 6 days of treatment in a dose-dependent manner. The samples SFV, DSFV and Fr-1 inhibited the precipitation and synthesis of chitin in the cuticle after 12 and 14 days of treatment. In the case of the four samples, the AChE was significantly improved after 14 days of treatment.

Natural Non-Mulberry Silk Nanoparticles for Potential-Controlled Drug Release

PubMed Central

Wang, Juan; Yin, Zhuping; Xue, Xiang; Kundu, Subhas C.; Mo, Xiumei; Lu, Shenzhou

2016-01-01

Natural silk protein nanoparticles are a promising biomaterial for drug delivery due to their pleiotropic properties, including biocompatibility, high bioavailability, and biodegradability. Chinese oak tasar Antheraea pernyi silk fibroin (ApF) nanoparticles are easily obtained using cations as reagents under mild conditions. The mild conditions are potentially advantageous for the encapsulation of sensitive drugs and therapeutic molecules. In the present study, silk fibroin protein nanoparticles are loaded with differently-charged small-molecule drugs, such as doxorubicin hydrochloride, ibuprofen, and ibuprofen-Na, by simple absorption based on electrostatic interactions. The structure, morphology and biocompatibility of the silk nanoparticles in vitro are investigated. In vitro release of the drugs from the nanoparticles depends on charge-charge interactions between the drugs and the nanoparticles. The release behavior of the compounds from the nanoparticles demonstrates that positively-charged molecules are released in a more prolonged or sustained manner. Cell viability studies with L929 demonstrated that the ApF nanoparticles significantly promoted cell growth. The results suggest that Chinese oak tasar Antheraea pernyi silk fibroin nanoparticles can be used as an alternative matrix for drug carrying and controlled release in diverse biomedical applications. PMID:27916946

The advances and perspectives of recombinant protein production in the silk gland of silkworm Bombyx mori.

PubMed

Xu, Hanfu

2014-10-01

The silk gland of silkworm Bombyx mori, is one of the most important organs that has been fully studied and utilized so far. It contributes finest silk fibers to humankind. The silk gland has excellent ability of synthesizing silk proteins and is a kind tool to produce some useful recombinant proteins, which can be widely used in the biological, biotechnical and pharmaceutical application fields. It's a very active area to express recombinant proteins using the silk gland as a bioreactor, and great progress has been achieved recently. This review recapitulates the progress of producing recombinant proteins and silk-based biomaterials in the silk gland of silkworm in addition to the construction of expression systems. Current challenges and future trends in the production of valuable recombinant proteins using transgenic silkworms are also discussed.

Oak Leaftier and Oak Leafroller (Pest Alert)

Treesearch

USDA Forest Service

1998-01-01

The oak leaftier, Croesia semipurpurana (Kearfott), and the oak leafroller, Archips semiferanus (Walker), are important Tortricidae moths in a complex of native species feeding in the early spring on oak foliage throughout the forests of Eastern North America. Outbreaks periodically develop with frequent and severe defoliation resulting in tree mortality. The last...

Evaluation of the innate immune-stimulating activity of amazake using a silkworm muscle contraction assay.

PubMed

Maruki-Uchida, Hiroko; Sai, Masahiko; Sekimizu, Kazuhisa

2017-11-22

We evaluated the innate immune-stimulating activity of amazake using a silkworm muscle contraction assay. Sake cake, a raw material used to make amazake, had high innate immunity-stimulating activity, whereas rice malt, another raw material used to make amazake, did not, even after fermentation. These results suggest that the silkworm muscle contraction assay is a useful tool to screen foods with high innate immune-stimulating activity and that amazake made from sake cake has immunomodulatory potential.

Isolation and characterization of lipase-producing bacteria in the intestine of the silkworm, Bombyx mori, reared on different forage.

PubMed

Feng, Wei; Wang, Xiao-Qiang; Zhou, Wei; Liu, Guang-Ying; Wan, Yong-Ji

2011-01-01

The silkworm, Bombyx mori L. (Lepidoptera: Bombycidae), an oligophagous insect that mainly feeds on mulberry leaves, is susceptible to entomopathogen infection when reared with tricuspid cudrania leaves. A total of 56 dominant bacterial strains, classified into 12 phylotypes based on bacteriological properties and analysis of 16S rRNA genes, were isolated from the intestine of the fourth and fifth instar silkworm larvae. Ten and seven phylotypes exist in the intestine of the silkworm larvae reared with mulberry leaves and tricuspid cudrania leaves, respectively. Four of them are common in the intestine of the two treatment groups. By screening their lipolytic ability on a Rhodamine B agar plate, nine lipase-producing bacterial strains were obtained and classified into six genera, including Bacillus, Brevibacterium, Corynebacterium, Staphylococcus, Klebsiella, and Stenotrophomonas. Except for Stenotrophomonas, which is common in both, the other genera only exist in the intestine of the silkworm larvae fed with mulberry leaves. In addition, by culture and fermentation in vitro, the maximum cell density and lipase activity of lipase-producing bacteria were examined at about 48 hours. The results indicate that diet has a significant impact on the gut bacterial community, especially lipase-producing bacteria. We suggest that the difference of lipase-producing bacterial diversity might be related to disease resistance of the silkworm.

A Review of the Implications of Heterozygosity and Inbreeding on Germplasm Biodiversity and Its Conservation in the Silkworm, Bombyx mori

PubMed Central

Jingade, A.H.; Vijayan, K.; Somasundaram, P.; Srivasababu, G.K.; Kamble, C.K.

2011-01-01

Silkworm genebanks assume paramount importance as the reservoirs of biodiversity and source of alleles that can be easily retrieved for genetic enhancement of popular breeds. More than 4000 Bombyx mori L (Lepidoptera: Bombycidae) strains are currently available and these strains are maintained through continuous sibling mating. This repeated sibling mating makes the populations of each strain more homozygous, but leads to loss of unique and valuable genes through the process of inbreeding depression. Hence, it is essential to maintain a minimal degree of heterozygosity within the population of each silkworm strain, especially in the traditional geographic strains, to avoid such loss. As a result, accurate estimation of genetic diversity is becoming more important in silkworm genetic resources conservation. Application of molecular markers help estimate genetic diversity much more accurately than that of morphological traits. Since a minimal amount of heterozygosity in each silkworm strain is essential for better conservation by avoiding inbreeding depression, this article overviews both theoretical and practical importance of heterozygosity together with impacts of inbreeding depression and the merits and demerits of neutral molecular markers for measurements of both heterozygosity and inbreeding depression in the silkworm Bombyx mori. PMID:21521139

A review of the implications of heterozygosity and inbreeding on germplasm biodiversity and its conservation in the silkworm, Bombyx mori.

PubMed

Jingade, A H; Vijayan, K; Somasundaram, P; Srivasababu, G K; Kamble, C K

2011-01-01

Abstract Silkworm genebanks assume paramount importance as the reservoirs of biodiversity and source of alleles that can be easily retrieved for genetic enhancement of popular breeds. More than 4000 Bombyx mori L (Lepidoptera: Bombycidae) strains are currently available and these strains are maintained through continuous sibling mating. This repeated sibling mating makes the populations of each strain more homozygous, but leads to loss of unique and valuable genes through the process of inbreeding depression. Hence, it is essential to maintain a minimal degree of heterozygosity within the population of each silkworm strain, especially in the traditional geographic strains, to avoid such loss. As a result, accurate estimation of genetic diversity is becoming more important in silkworm genetic resources conservation. Application of molecular markers help estimate genetic diversity much more accurately than that of morphological traits. Since a minimal amount of heterozygosity in each silkworm strain is essential for better conservation by avoiding inbreeding depression, this article overviews both theoretical and practical importance of heterozygosity together with impacts of inbreeding depression and the merits and demerits of neutral molecular markers for measurements of both heterozygosity and inbreeding depression in the silkworm Bombyx mori.

2A self-cleaving peptide-based multi-gene expression system in the silkworm Bombyx mori

PubMed Central

Wang, Yuancheng; Wang, Feng; Wang, Riyuan; Zhao, Ping; Xia, Qingyou

2015-01-01

Fundamental and applied studies of silkworms have entered the functional genomics era. Here, we report a multi-gene expression system (MGES) based on 2A self-cleaving peptide (2A), which regulates the simultaneous expression and cleavage of multiple gene targets in the silk gland of transgenic silkworms. First, a glycine-serine-glycine spacer (GSG) was found to significantly improve the cleavage efficiency of 2A. Then, the cleavage efficiency of six types of 2As with GSG was analyzed. The shortest porcine teschovirus-1 2A (P2A-GSG) exhibited the highest cleavage efficiency in all insect cell lines that we tested. Next, P2A-GSG successfully cleaved the artificial human serum albumin (66 kDa) linked with human acidic fibroblast growth factor (20.2 kDa) fusion genes and vitellogenin receptor fragment (196 kD) of silkworm linked with EGFP fusion genes, importantly, vitellogenin receptor protein was secreted to the outside of cells. Furthermore, P2A-GSG successfully mediated the simultaneous expression and cleavage of a DsRed and EGFP fusion gene in silk glands and caused secretion into the cocoon of transgenic silkworms using our sericin1 expression system. We predicted that the MGES would be an efficient tool for gene function research and innovative research on various functional silk materials in medicine, cosmetics, and other biomedical areas. PMID:26537835

Molecular architecture of silk fibroin of Indian golden silkmoth, Antheraea assama.

PubMed

Gupta, Adarsh K; Mita, Kazuei; Arunkumar, Kallare P; Nagaraju, Javaregowda

2015-08-03

The golden silk spun by Indian golden silkmoth Antheraea assama, is regarded for its shimmering golden luster, tenacity and value as biomaterial. This report describes the gene coding for golden silk H-fibroin (AaFhc), its expression, full-length sequence and structurally important motifs discerning the underlying genetic and biochemical factors responsible for its much sought-after properties. The coding region, with biased isocodons, encodes highly repetitious crystalline core, flanked by a pair of 5' and 3' non-repetitious ends. AaFhc mRNA expression is strictly territorial, confined to the posterior silk gland, encoding a protein of size 230 kDa, which makes homodimers making the elementary structural units of the fibrous core of the golden silk. Characteristic polyalanine repeats that make tight β-sheet crystals alternate with non-polyalanine repeats that make less orderly antiparallel β-sheets, β-turns and partial α-helices. Phylogenetic analysis of the conserved N-terminal amorphous motif and the comparative analysis of the crystalline region with other saturniid H-fibroins reveal that AaFhc has longer, numerous and relatively uniform repeat motifs with lower serine content that assume tighter β-crystals and denser packing, which are speculated to be responsible for its acclaimed properties of higher tensile strength and higher refractive index responsible for golden luster.

Transcriptional Profiling of Midgut Immunity Response and Degeneration in the Wandering Silkworm, Bombyx mori

PubMed Central

Xiao, Guohua; Yang, Bing; Zhang, Jie; Li, Xuquan; Guan, Jingmin; Shao, Qimiao; Beerntsen, Brenda T.; Zhang, Peng; Wang, Chengshu; Ling, Erjun

2012-01-01

Background Lepidoptera insects have a novel development process comprising several metamorphic stages during their life cycle compared with vertebrate animals. Unlike most Lepidoptera insects that live on nectar during the adult stage, the Bombyx mori silkworm adults do not eat anything and die after egg-laying. In addition, the midguts of Lepidoptera insects produce antimicrobial proteins during the wandering stage when the larval tissues undergo numerous changes. The exact mechanisms responsible for these phenomena remain unclear. Principal Findings We used the silkworm as a model and performed genome-wide transcriptional profiling of the midgut between the feeding stage and the wandering stage. Many genes concerned with metabolism, digestion, and ion and small molecule transportation were down-regulated during the wandering stage, indicating that the wandering stage midgut loses its normal functions. Microarray profiling, qRT-PCR and western blot proved the production of antimicrobial proteins (peptides) in the midgut during the wandering stage. Different genes of the immune deficiency (Imd) pathway were up-regulated during the wandering stage. However, some key genes belonging to the Toll pathway showed no change in their transcription levels. Unlike butterfly (Pachliopta aristolochiae), the midgut of silkworm moth has a layer of cells, indicating that the development of midgut since the wandering stage is not usual. Cell division in the midgut was observed only for a short time during the wandering stage. However, there was extensive cell apoptosis before pupation. The imbalance of cell division and apoptosis probably drives the continuous degeneration of the midgut in the silkworm since the wandering stage. Conclusions This study provided an insight into the mechanism of the degeneration of the silkworm midgut and the production of innate immunity-related proteins during the wandering stage. The imbalance of cell division and apoptosis induces irreversible

The nicotinic acetylcholine receptor gene family of the silkworm, Bombyx mori

PubMed Central

Shao, Ya-Ming; Dong, Ke; Zhang, Chuan-Xi

2007-01-01

Background Nicotinic acetylcholine receptors (nAChRs) mediate fast synaptic cholinergic transmission in the insect central nervous system. The insect nAChR is the molecular target of a class of insecticides, neonicotinoids. Like mammalian nAChRs, insect nAChRs are considered to be made up of five subunits, coded by homologous genes belonging to the same family. The nAChR subunit genes of Drosophila melanogaster, Apis mellifera and Anopheles gambiae have been cloned previously based on their genome sequences. The silkworm Bombyx mori is a model insect of Lepidoptera, among which are many agricultural pests. Identification and characterization of B. mori nAChR genes could provide valuable basic information for this important family of receptor genes and for the study of the molecular mechanisms of neonicotinoid action and resistance. Results We searched the genome sequence database of B. mori with the fruit fly and honeybee nAChRs by tBlastn and cloned all putative silkworm nAChR cDNAs by reverse transcriptase-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) methods. B. mori appears to have the largest known insect nAChR gene family to date, including nine α-type subunits and three β-type subunits. The silkworm possesses three genes having low identity with others, including one α and two β subunits, α9, β2 and β3. Like the fruit fly and honeybee counterparts, silkworm nAChR gene α6 has RNA-editing sites, and α4, α6 and α8 undergo alternative splicing. In particular, alternative exon 7 of Bmα8 may have arisen from a recent duplication event. Truncated transcripts were found for Bmα4 and Bmα5. Conclusion B. mori possesses a largest known insect nAChR gene family characterized to date, including nine α-type subunits and three β-type subunits. RNA-editing, alternative splicing and truncated transcripts were found in several subunit genes, which might enhance the diversity of the gene family. PMID:17868469

Oak decline and red oak borer outbreak: impact in upland oak-hickory forests of Arkansas, USA

Treesearch

Laurel J. Haavik; Joshua S. Jones; Larry D. Galligan; James M. Guldin; Fred M. Stephen

2012-01-01

Oak-hickory forests in the Ozark and Ouachita Mountains of Arkansas recently experienced an episode of oak mortality in concert with an outbreak of the red oak borer (Enaphalodes rufulus (Haldeman) (Coleoptera: Cerambycidae)). We utilized data from the Forest Inventory and Analysis (FIA) program of the USDA Forest Service to explore changes in percent red oak (Quercus...

Oak Tree Preservation in Thousand Oaks, California

Treesearch

William F. Elmendorf

1991-01-01

The City of Thousand Oaks over the last 20 years has taken aggressive steps to preserve and protect the City's namesake, the oak tree. First adopted in 1972 as an Emergency City Council Proclamation, the City's Oak Tree Ordinance has been considered by some, to be one of the first and toughest municipal native tree preservation ordinances within the State of...

Silvernanotherapy on the viral borne disease of silkworm Bombyx mori L.

NASA Astrophysics Data System (ADS)

Govindaraju, K.; Tamilselvan, S.; Kiruthiga, V.; Singaravelu, G.

2011-12-01

Antiviral assays of chemically and biologically synthesized silver nanoparticles were made against BmNPV ( Bombyx mori Nuclear Polyhedrosis Virus). Reduction of silver ions by sodium citrate and Spirulina platensis led to the formation of spherical silver nanoparticles of 40-60 and 7-16 nm size. Single cell protein ( Spirulina platensis)-synthesized silver nanoparticles showed the strongest antiviral activity. Immunological studies made on the silkworm Bombyx mori disclosed that a significant increase in the total hemocyte count and differential hemocyte count due to S. platensis-synthesized silver nanoparticles supplementation. Improvement in the defense mechanism was noticed from the strengthened peritrophic membrane of the digestive tract and the increased total protein. Overall, the results presented illustrate that single cell protein-synthesized silver nanoparticles supplementation is effective in controlling viral-borne diseases of the silkworm.

Differentially expressed genes in the silk gland of silkworm (Bombyx mori) treated with TiO2 NPs.

PubMed

Xue, Bin; Li, Fanchi; Hu, Jingsheng; Tian, Jianghai; Li, Jinxin; Cheng, Xiaoyu; Hu, Jiahuan; Li, Bing

2017-05-05

Silk gland is a silkworm organ where silk proteins are synthesized and secreted. Dietary supplement of TiO 2 nanoparticles (NPs) promotes silk protein synthesis in silkworms. In this study, digital gene expression (DGE) tag was used to analyze the gene expression profile of the posterior silk gland of silkworms that were fed with TiO 2 NPs. In total, 5,702,823 and 6,150,719 clean tags, 55,096 and 74,715 distinct tags were detected in TiO 2 NPs treated and control groups, respectively. Compared with the control, TiO 2 NPs treated silkworms showed 306 differentially expressed genes, including 137 upregulated genes and 169 downregulated genes. Of these differentially expressed genes, 106 genes were related to silk protein synthesis, among which 97 genes were upregulated and 9 genes were downregulated. Pathway mapping using the Kyoto Encyclopedia of Genes and Genomes (KEGG) showed that 20 pathways were significantly enriched in TiO 2 NPs treated silkworms, and the metabolic pathway-related genes were the most significantly enriched. The DGE results were verified by qRT-PCR analysis of eight differentially expressed genes. The DGE and qRT-PCR results were consistent for all three upregulated genes and three of the five downregulated genes, but the expression trends of the remaining two genes were different between qRT-PCR and DGE analysis. This study enhances our understanding of the mechanism of TiO 2 NPs promoted silk protein synthesis. Copyright © 2017 Elsevier B.V. All rights reserved.

Mechanical properties of cocoons constructed consecutively by a single silkworm caterpillar, Bombyx mori

NASA Astrophysics Data System (ADS)

Huang, S. Q.; Zhao, H. P.; Feng, X. Q.; Cui, W.; Lin, Z.; Xu, M. Q.

2008-04-01

Most animals have the ability to adapt, to some extends and in different ways, the variation or disturbance of environment. In our experiments, we forced a silkworm caterpillar to spin two, three or four thin cocoons by taking it out from the cocoon being constructed. The mechanical properties of these cocoons were studied by static tensile tests and dynamic mechanical thermal analysis. Though external disturbances may cause the decrease in the total weight of silk spun by the silkworm, a gradual enhancement was interestingly found in the mechanical properties of these thin cocoons. Scanning electron microscopy observations of the fractured specimens of the cocoons showed that there exist several different energy dissipation mechanisms occurred simultaneously at macro-, meso-, and micro-scales, yielding a superior capacity of cocoons to adsorb the energy of possible attacks from the outside and to protect efficiently its pupa against damage. Through evolution of millions of years, therefore, the silkworm Bombyx mori seems to have gained the ability to adapt external disturbances and to redesign a new cocoon with optimized protective function when its first cocoon has been damaged for some reasons.

Animal welfare and use of silkworm as a model animal.

PubMed

Sekimizu, N; Paudel, A; Hamamoto, H

2012-08-01

Sacrificing model animals is required for developing effective drugs before being used in human beings. In Japan today, at least 4,210,000 mice and other mammals are sacrificed to a total of 6,140,000 per year for the purpose of medical studies. All the animals treated in Japan, including test animals, are managed under control of "Act on Welfare and Management of Animals". Under the principle of this Act, no person shall kill, injure, or inflict cruelty on animals without due cause. "Animal" addressed in the Act can be defined as a "vertebrate animal". If we can make use of invertebrate animals in testing instead of vertebrate ones, that would be a remarkable solution for the issue of animal welfare. Furthermore, there are numerous advantages of using invertebrate animal models: less space and small equipment are enough for taking care of a large number of animals and thus are cost-effective, they can be easily handled, and many biological processes and genes are conserved between mammals and invertebrates. Today, many invertebrates have been used as animal models, but silkworms have many beneficial traits compared to mammals as well as other insects. In a Genome Pharmaceutical Institute's study, we were able to achieve a lot making use of silkworms as model animals. We would like to suggest that pharmaceutical companies and institutes consider the use of the silkworm as a model animal which is efficacious both for financial value by cost cutting and ethical aspects in animals' welfare.

Evaluation of propiconazole operational treatments of oaks for oak wilt control

Treesearch

Jordan Eggers; Jennifer Juzwik; Shawn Bernick; Lori Mordaunt

2005-01-01

Oaks commercially treated with propiconazole on 29 sites in Minnesota in 1998 were evaluated for efficacy in controlling oak wilt. Root graft spread occurred in 39 percent of preventively treated red oaks over 5 years; spread in white oaks occurred only once. Propiconazole generally prevented further disease symptom development in white oaks.

A comparative analysis of serpin genes in the silkworm genome

PubMed Central

Zou, Zhen; Picheng, Zhao; Weng, Hua; Mita, Kazuei; Jiang, Haobo

2009-01-01

Serine protease inhibitors (serpins) are a superfamily of proteins, most of which control protease-mediated processes by inhibiting their cognate enzymes. Sequencing of the silkworm genome provides an opportunity to investigate serpin structure, function, and evolution at the genome level. There are thirty-four serpin genes in Bombyx mori. Six are highly similar to their Manduca sexta orthologs that regulate innate immunity. Three alternative exons in serpin1 gene and four in serpin28 encode a variable region including the reactive site loop. Splicing of serpin2 pre-mRNA yields variations in serpin2A, 2A′ and 2B. Sequence similarity and intron positions reveal the evolutionary pathway of seven serpin genes in group C. RT-PCR indicates an increase in the mRNA levels of serpin1, 3, 5, 6, 9, 12, 13, 25, 27, 32 and 34 in fat body and hemocytes of larvae injected with bacteria. These results suggest that the silkworm serpins play regulatory roles in defense responses. PMID:19150649

[Effect of fluoride on gut microflora of silkworm (Bombyx mori)].

PubMed

Li, Guannan; Xia, Xuejuan; Sendegeya, Parfait; Zhao, Huanhuan; Long, Yaohang; Zhu, Yong

2015-07-04

We examined the effect of fluoride on gut microflora of silkworm. After DNA extraction and PCR amplification, clone libraries of 16S rRNA gene fragment were constructed. Amplified ribosomal DNA restriction analysis (ARDRA) was performed by digestion of the 16S rRNA gene, and each unique restriction fragment polymorphism pattern was designated as an operational taxonomic unit (OTU). A total of 14 OTUs were identified from intestinal samples of both T6 and 734. Phylogenetic trees of bacterial 16S rRNA nucleotide sequences were constructed and analyzed. Furthermore, the dominant bacteria were studied by the nested polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DDGE) technology. After fluorosis, the flora of Enterococcus and Bacillus reduced. However, the flora of Staphylococcus increased. Fluoride can destroy the balance of microflora in the gut of silkworm by changing the bacteria diversity and proportion, which has bigger effect to 734 than T6.

Production of an active feline interferon in the cocoon of transgenic silkworms using the fibroin H-chain expression system

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

Kurihara, H.; Sezutsu, H.; Tamura, T.

2007-04-20

We constructed the fibroin H-chain expression system to produce recombinant proteins in the cocoon of transgenic silkworms. Feline interferon (FeIFN) was used for production and to assess the quality of the product. Two types of FeIFN fusion protein, each with N- and C-terminal sequences of the fibroin H-chain, were designed to be secreted into the lumen of the posterior silk glands. The expression of the FeIFN/H-chain fusion gene was regulated by the fibroin H-chain promoter domain. The transgenic silkworms introduced these constructs with the piggyBac transposon-derived vector, which produced the normal sized cocoons containing each FeIFN/H-chain fusion protein. Although themore » native-protein produced by transgenic silkworms have almost no antiviral activity, the proteins after the treatment with PreScission protease to eliminate fibroin H-chain derived N- and C-terminal sequences from the products, had very high antiviral activity. This H-chain expression system, using transgenic silkworms, could be an alternative method to produce an active recombinant protein and silk-based biomaterials.« less

BmCyclin B and BmCyclin B3 are required for cell cycle progression in the silkworm, Bombyx mori.

PubMed

Pan, Minhui; Hong, Kaili; Chen, Xiangyun; Pan, Chun; Chen, Xuemei; Kuang, Xiuxiu; Lu, Cheng

2013-04-01

Cyclin B is an important regulator of the cell cycle G2 to M phase transition. The silkworm genomic database shows that there are two Cyclin B genes in the silkworm (Bombyx mori), BmCyclin B and BmCyclin B3. Using silkworm EST data, the cyclin B3 (EU074796) gene was cloned. Its complete cDNA was 1665 bp with an ORF of 1536 bp derived from seven exons and six introns. The BmCyclin B3 gene encodes 511 amino acids, and the predicted molecular weight is 57.8 kD with an isoelectric point of 9.18. The protein contains one protein damage box and two cyclin boxes. RNA interference-mediated reduction of BmCyclin B and BmCyclin B3 expression induced cell cycle arrest in G2 or M phase in BmN-SWU1 cells, thus inhibiting cell proliferation. These results suggest that BmCyclin B and BmCyclin B3 are necessary for completing the cell cycle in silkworm cells.

Diet-consumer nitrogen isotope fractionation for prolonged fasting arthropods.

PubMed

Mizota, Chitoshi; Yamanaka, Toshiro

2011-12-01

Nitrogen acquisition for cellular metabolism during diapause is a primary concern for herbivorous arthropods. Analyses of naturally occurring stable isotopes of nitrogen help elucidate the mechanism. Relevant articles have cited (58 times up to mid-June 2011) anomalously elevated δ(15)N (per mil deviation of (15)N/(14)N, relative to atmospheric nitrogen=0 ‰) values (diet-consumer nitrogen isotope fractionation; up to 12 ‰) for a prolonged fasting raspberry beetle (Byturus tomentosus Degeer (Coleoptera: Byturidae)), which feeds on red raspberries (Rubus idaeus: δ(15)N= ~ +2 ‰). Biologists have hypothesised that extensive recycling of amino acid nitrogen is responsible for the prolonged fasting. Since this hypothesis was proposed in 1995, scientists have integrated biochemical and molecular knowledge to support the mechanism of prolonged diapausing of animals. To test the validity of the recycling hypothesis, we analysed tissue nitrogen isotope ratios for four Japanese arthropods: the shield bug Parastrachia japonensis Scott (Hemiptera: Cydnidae), the burrower bug Canthophorus niveimarginatus Scott (Hemiptera: Cydnidae), leaf beetle Gastrophysa atrocyanea Motschulsky (Coleoptera: Chrysomelidae) and the Japanese oak silkworm Antheraea yamamai (Lepidoptera: Saturniidae), all of which fast for more than 6 months as part of their life-history strategy. Resulting diet-consumer nitrogen isotope discrimination during fasting ranged from 0 to 7‰, as in many commonly known terrestrial arthropods. We conclude that prolonged fasting of arthropods does not always result in anomalous diet-consumer nitrogen isotope fractionation, since the recycling process is closed or nearly closed with respect to nitrogen isotopes.

The genomic underpinnings of apoptosis in the silkworm, Bombyx mori

PubMed Central

2010-01-01

Background Apoptosis is regulated in an orderly fashion by a series of genes, and has a crucial role in important physiological processes such as growth development, immunological response and so on. Recently, substantial studies have been undertaken on apoptosis in model animals including humans, fruit flies, and the nematode. However, the lack of genomic data for silkworms limits their usefulness in apoptosis studies, despite the advantages of silkworm as a representative of Lepidoptera and an effective model system. Herein we have identified apoptosis-related genes in the silkworm Bombyx mori and compared them to those from insects, mammals, and nematodes. Results From the newly assembled genome databases, a genome-wide analysis of apoptosis-related genes in Bombyx mori was performed using both nucleotide and protein Blast searches. Fifty-two apoptosis-related candidate genes were identified, including five caspase family members, two tumor necrosis factor (TNF) superfamily members, one Bcl-2 family member, four baculovirus IAP (inhibitor of apoptosis) repeat (BIR) domain family members and 1 RHG (Reaper, Hid, Grim, and Sickle; Drosophila cell death activators) family member. Moreover, we identified a new caspase family member, BmCaspase-New, two splice variants of BmDronc, and Bm3585, a mammalian TNF superfamily member homolog. Twenty-three of these apoptosis-related genes were cloned and sequenced using cDNA templates isolated from BmE-SWU1 cells. Sequence analyses revealed that these genes could have key roles in apoptosis. Conclusions Bombyx mori possesses potential apoptosis-related genes. We hypothesized that the classic intrinsic and extrinsic apoptotic pathways potentially are active in Bombyx mori. These results lay the foundation for further apoptosis-related study in Bombyx mori. PMID:21040523

Bombykol receptors in the silkworm moth and the fruit fly

PubMed Central

Syed, Zainulabeuddin; Kopp, Artyom; Kimbrell, Deborah A.; Leal, Walter S.

2010-01-01

Male moths are endowed with odorant receptors (ORs) to detect species-specific sex pheromones with remarkable sensitivity and selectivity. We serendipitously discovered that an endogenous OR in the fruit fly, Drosophila melanogaster, is highly sensitive to the sex pheromone of the silkworm moth, bombykol. Intriguingly, the fruit fly detectors are more sensitive than the receptors of the silkworm moth, although its ecological significance is unknown. By expression in the “empty neuron” system, we identified the fruit fly bombykol-sensitive OR as DmelOR7a (= DmOR7a). The profiles of this receptor in response to bombykol in the native sensilla (ab4) or expressed in the empty neuron system (ab3 sensilla) are indistinguishable. Both WT and transgenic flies responded with high sensitivity, in a dose-dependent manner, and with rapid signal termination. In contrast, the same empty neuron expressing the moth bombykol receptor, BmorOR1, demonstrated low sensitivity and slow signal inactivation. When expressed in the trichoid sensilla T1 of the fruit fly, the neuron housing BmorOR1 responded with sensitivity comparable to that of the native trichoid sensilla in the silkworm moth. By challenging the native bombykol receptor in the fruit fly with high doses of another odorant to which the receptor responds with the highest sensitivity, we demonstrate that slow signal termination is induced by overdose of a stimulus. As opposed to the empty neuron system in the basiconic sensilla, the structural, biochemical, and/or biophysical features of the sensilla make the T1 trichoid system of the fly a better surrogate for the moth receptor. PMID:20439725

Sudden oak death disease progression in oaks and tanoaks

Treesearch

Brice A. McPherson; Sylvia R. Mori; David L. Wood; Andrew J. Storer; Pavel Svihra; N. Maggi Kelly; Richard B. Standiford

2006-01-01

In March 2000, we established twenty disease progression plots in Marin County to monitor the progress of sudden oak death symptoms in coast live oak (Quercus agrifolia), California black oak (Q. kelloggii), and tanoak (Lithocarpus densiflorus) (McPherson and others 2005). Plots were located to encompass a...

Roles of silkworm endoplasmic reticulum chaperones in the secretion of recombinant proteins expressed by baculovirus system.

PubMed

Imai, Saki; Kusakabe, Takahiro; Xu, Jian; Li, Zhiqing; Shirai, Shintaro; Mon, Hiroaki; Morokuma, Daisuke; Lee, Jae Man

2015-11-01

Baculovirus expression vector system (BEVS) is widely used for production of recombinant eukaryotic proteins in insect larvae or cultured cells. BEVS has advantages over bacterial expression system in producing post-translationally modified secreted proteins. However, for some unknown reason, it is very difficult for insects to secrete sufficiently for certain proteins of interest. To understand the reasons why insect cells fail to secrete some kinds of recombinant proteins, we here employed three mammalian proteins as targets, EPO, HGF, and Wnt3A, with different secretion levels in BEVS and investigated their mRNA transcriptions from the viral genome, subcellular localizations, and interactions with silkworm ER chaperones. Moreover, we observed that no significantly influence on the secretion amounts of all three proteins when depleting or overexpressing most endogenous ER chaperone genes in cultured silkworm cells. However, among all detected ER chaperones, the depletion of BiP severely decreased the recombinant protein secretion in BEVS, indicating the possible central role of Bip in silkworm secretion pathway.

Efficacy of silkworm (Bombyx mori L.) chrysalis oil as a lipid source in adult Wistar rats.

PubMed

Mentang, Feny; Maita, Masashi; Ushio, Hideki; Ohshima, Toshiaki

2011-08-01

The effects of silkworm chrysalis oil, rich in n-3 α-linolenic acid (ALA), on lipid metabolism in Wistar rats were investigated. The rats were fed diets containing 7% soybean oil (control), silkworm chrysalis oil (SWO), or fish oil (FO) for 8weeks. Plasma triglyceride and glucose levels were significantly lower in the SWO group after 8weeks compared to the control and FO groups. The total cholesterol and blood urea nitrogen levels were higher in the control group than in the SWO and FO groups at 8weeks post-consumption. However, aspartate amino transferase and alanine amino transferase levels were not significantly different among all groups. A higher arachidonic acid (AA) content was detected in the control group, while lower AA levels were observed with the increase in EPA and DHA in the SWO and FO groups. These results suggest that n-3 α-linolenic acid-rich silkworm chrysalis oil can improve hyperlipidaemia and hyperglycaemia. Copyright © 2011 Elsevier Ltd. All rights reserved.

Characterization and expression patterns of let-7 microRNA in the silkworm (Bombyx mori).

PubMed

Liu, Shiping; Xia, Qingyou; Zhao, Ping; Cheng, Tingcai; Hong, Kaili; Xiang, Zhonghuai

2007-07-25

lin-4 and let-7, the two founding members of heterochronic microRNA genes, are firstly confirmed in Caenorhabditis elegans to control the proper timing of developmental programs in a heterochronic pathway. let-7 has been thought to trigger the onset of adulthood across animal phyla. Ecdysone and Broad-Complex are required for the temporal expression of let-7 in Drosophila melanogaster. For a better understanding of the conservation and functions of let-7, we seek to explore how it is expressed in the silkworm (Bombyx mori). One member of let-7 family has been identified in silkworm computationally and experimentally. All known members of this family share the same nucleotides at ten positions within the mature sequences. Sequence logo and phylogenetic tree show that they are not only conserved but diversify to some extent among some species. The bmo-let-7 was very lowly expressed in ova harvested from newborn unmated female adult and in individuals from the first molt to the early third instar, highly expressed after the third molt, and the most abundant expression was observed after mounting, particularly after pupation. The expression levels were higher at the end of each instar and at the beginning of each molt than at other periods, coinciding with the pulse of ecdysone and BR-C as a whole. Using cultured ovary cell line, BmN-SWU1, we examined the effect of altered ecdysone levels on bmo-let-7 expression. The expression was also detected in various tissues of day 3 of the fifth instar and of from day 7 of the fifth to pupa, suggesting a wide distributing pattern with various signal intensities. bmo-let-7 is stage- and tissue-specifically expressed in the silkworm. Although no signals were detected during embryonic development and first larval instar stages, the expression of bmo-let-7 was observed from the first molt, suggesting that it might also function at early larval stage of the silkworm. The detailed expression profiles in the whole life cycle and

Design and optimization of an experimental bioregenerative life support system with higher plants and silkworms

NASA Astrophysics Data System (ADS)

Hu, Enzhu; Bartsev, Sergey I.; Zhao, Ming; Liu, Professor Hong

The conceptual scheme of an experimental bioregenerative life support system (BLSS) for planetary exploration was designed, which consisted of four elements - human metabolism, higher plants, silkworms and waste treatment. 15 kinds of higher plants, such as wheat, rice, soybean, lettuce, mulberry, et al., were selected as regenerative component of BLSS providing the crew with air, water, and vegetable food. Silkworms, which producing animal nutrition for crews, were fed by mulberry-leaves during the first three instars, and lettuce leaves last two instars. The inedible biomass of higher plants, human wastes and silkworm feces were composted into soil like substrate, which can be reused by higher plants cultivation. Salt, sugar and some household material such as soap, shampoo would be provided from outside. To support the steady state of BLSS the same amount and elementary composition of dehydrated wastes were removed periodically. The balance of matter flows between BLSS components was described by the system of algebraic equations. The mass flows between the components were optimized by EXCEL spreadsheets and using Solver. The numerical method used in this study was Newton's method.

Genomic analysis of carboxyl/cholinesterase genes in the silkworm Bombyx mori

PubMed Central

2010-01-01

Background Carboxyl/cholinesterases (CCEs) have pivotal roles in dietary detoxification, pheromone or hormone degradation and neurodevelopment. The recent completion of genome projects in various insect species has led to the identification of multiple CCEs with unknown functions. Here, we analyzed the phylogeny, expression and genomic distribution of 69 putative CCEs in the silkworm, Bombyx mori (Lepidoptera: Bombycidae). Results A phylogenetic tree of CCEs in B. mori and other lepidopteran species was constructed. The expression pattern of each B. mori CCE was also investigated by a search of an expressed sequence tag (EST) database, and the relationship between phylogeny and expression was analyzed. A large number of B. mori CCEs were identified from a midgut EST library. CCEs expressed in the midgut formed a cluster in the phylogenetic tree that included not only B. mori genes but also those of other lepidopteran species. The silkworm, and possibly also other lepidopteran species, has a large number of CCEs, and this might be a consequence of the large cluster of midgut CCEs. Investigation of intron-exon organization in B. mori CCEs revealed that their positions and splicing site phases were strongly conserved. Several B. mori CCEs, including juvenile hormone esterase, not only showed clustering in the phylogenetic tree but were also closely located on silkworm chromosomes. We investigated the phylogeny and microsynteny of neuroligins in detail, among many CCEs. Interestingly, we found the evolution of this gene appeared not to be conserved between B. mori and other insect orders. Conclusions We analyzed 69 putative CCEs from B. mori. Comparison of these CCEs with other lepidopteran CCEs indicated that they had conserved expression and function in this insect order. The analyses showed that CCEs were unevenly distributed across the genome of B. mori and suggested that neuroligins may have a distinct evolutionary history from other insect order. It is possible

Fire effects on Gambel oak in southwestern ponderosa pine-oak forests

Treesearch

Scott R. Abella; Peter Z. Fulé

2008-01-01

Gambel oak (Quercus gambelii) is ecologically and aesthetically valuable in southwestern ponderosa pine (Pinus ponderosa) forests. Fire effects on Gambel oak are important because fire may be used in pine-oak forests to manage oak directly or to accomplish other management objectives. We used published literature to: (1) ascertain...

Oak Symposium Proceedings

Treesearch

Northeastern Forest Experiment Station

1971-01-01

As "tall oaks from little acorns grow", the germ of an idea blossomed into this symposium on the five upland oaks. Called simply the "Oak Symposium", that's what it's all about - a meeting to bring together a summation of the advances made on the silviculture, management, and utilization of the upland oaks. Part of this process is the...

Bombyx mori histone methyltransferase BmAsh2 is essential for silkworm piRNA-mediated sex determination.

PubMed

Li, Zhiqian; You, Lang; Yan, Dong; James, Anthony A; Huang, Yongping; Tan, Anjiang

2018-02-01

Sex determination is a hierarchically-regulated process with high diversity in different organisms including insects. The W chromosome-derived Fem piRNA has been identified as the primary sex determination factor in the lepidopteran insect, Bombyx mori, revealing a distinctive piRNA-mediated sex determination pathway. However, the comprehensive mechanism of silkworm sex determination is still poorly understood. We show here that the silkworm PIWI protein BmSiwi, but not BmAgo3, is essential for silkworm sex determination. CRISPR/Cas9-mediated depletion of BmSiwi results in developmental arrest in oogenesis and partial female sexual reversal, while BmAgo3 depletion only affects oogenesis. We identify three histone methyltransferases (HMTs) that are significantly down-regulated in BmSiwi mutant moths. Disruption one of these, BmAsh2, causes dysregulation of piRNAs and transposable elements (TEs), supporting a role for it in the piRNA signaling pathway. More importantly, we find that BmAsh2 mutagenesis results in oogenesis arrest and partial female-to-male sexual reversal as well as dysregulation of the sex determination genes, Bmdsx and BmMasc. Mutagenesis of other two HMTs, BmSETD2 and BmEggless, does not affect piRNA-mediated sex determination. Histological analysis and immunoprecipitation results support a functional interaction between the BmAsh2 and BmSiwi proteins. Our data provide the first evidence that the HMT, BmAsh2, plays key roles in silkworm piRNA-mediated sex determination.

Conversion of an oak seed orchard to oak silvopasture

Treesearch

K. Connor; L. Dimov; R. Barlow; M. Smith; E. Kirkland

2013-01-01

The potential of hardwood silvopasture has yet to be realized in the Southeastern United States. The decommissioning of the Stauffer Nursery, Opelika, AL, provided the opportunity to intensively research hardwood silvopasture using various oak species. Average crown diameter ranged from 5.9 feet in white oak (Quercus alba) to 10.7 feet in Nuttall oak...

Silkworm Pupa Protein Hydrolysate Induces Mitochondria-Dependent Apoptosis and S Phase Cell Cycle Arrest in Human Gastric Cancer SGC-7901 Cells.

PubMed

Li, Xiaotong; Xie, Hongqing; Chen, Yajie; Lang, Mingzi; Chen, Yuyin; Shi, Liangen

2018-03-28

Silkworm pupae ( Bombyx mori ) are a high-protein nutrition source consumed in China since more than 2 thousand years ago. Recent studies revealed that silkworm pupae have therapeutic benefits to treat many diseases. However, the ability of the compounds of silkworm pupae to inhibit tumourigenesis remains to be elucidated. Here, we separated the protein of silkworm pupae and performed alcalase hydrolysis. Silkworm pupa protein hydrolysate (SPPH) can specifically inhibit the proliferation and provoke abnormal morphologic features of human gastric cancer cells SGC-7901 in a dose- and time-dependent manner. Moreover, flow cytometry indicated that SPPH can induce apoptosis and arrest the cell-cycle in S phase. Furthermore, SPPH was shown to provoke accumulation of reactive oxygen species (ROS) and depolarization of mitochondrial membrane potential. Western blotting analysis indicated that SPPH inhibited Bcl-2 expression and promoted Bax expression, and subsequently induced apoptosis-inducing factor and cytochrome C release, which led to the activation of initiator caspase-9 and executioner caspase-3, cleavage of poly (ADP-ribose) polymerase (PARP), eventually caused cell apoptosis. Moreover, SPPH-induced S-phase arrest was mediated by up-regulating the expression of E2F1 and down-regulating those of cyclin E, CDK2 and cyclin A2. Transcriptome sequencing and gene set enrichment analysis (GSEA) also revealed that SPPH treatment could affect gene expression and pathway regulation related to tumourigenesis, apoptosis and cell cycle. In summary, our results suggest that SPPH could specifically suppress cell growth of SGC-7901 through an intrinsic apoptotic pathway, ROS accumulation and cell cycle arrest, and silkworm pupae have a potential to become a source of anticancer agents in the future.

The homeodomain transcription factors antennapedia and POU-M2 regulate the transcription of the steroidogenic enzyme gene Phantom in the silkworm.

PubMed

Meng, Meng; Cheng, Dao-Jun; Peng, Jian; Qian, Wen-Liang; Li, Jia-Rui; Dai, Dan-Dan; Zhang, Tian-Lei; Xia, Qing-You

2015-10-02

The steroid hormone ecdysone, which controls insect molting and metamorphosis, is synthesized in the prothoracic gland (PG), and several steroidogenic enzymes that are expressed specifically in the PG are involved in ecdysteroidogenesis. In this study, we identified new regulators that are involved in the transcriptional control of the silkworm steroidogenic enzyme genes. In silico analysis predicted several potential cis-regulatory elements (CREs) for the homeodomain transcription factors Antennapedia (Antp) and POU-M2 in the proximal promoters of steroidogenic enzyme genes. Antp and POU-M2 are expressed dynamically in the PG during larval development, and their overexpression in silkworm embryo-derived (BmE) cells induced the expression of steroidogenic enzyme genes. Importantly, luciferase reporter analyses, electrophoretic mobility shift assays, and chromatin immunoprecipitation assays revealed that Antp and POU-M2 promote the transcription of the silkworm steroidogenic enzyme gene Phantom (Phm) by binding directly to specific motifs within overlapping CREs in the Phm promoter. Mutations of these CREs in the Phm promoter suppressed the transcriptional activities of both Antp and POU-M2 in BmE cells and decreased the activities of mutated Phm promoters in the silkworm PG. In addition, pulldown and co-immunoprecipitation assays demonstrated that Antp can interact with POU-M2. Moreover, RNA interference-mediated down-regulation of either Antp or POU-M2 during silkworm wandering not only decreased the ecdysone titer but also led to the failure of metamorphosis. In summary, our results suggest that Antp and POU-M2 coordinate the transcription of the silkworm Phm gene directly, indicating new roles for homeodomain proteins in regulating insect ecdysteroidogenesis. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

TIL-type protease inhibitors may be used as targeted resistance factors to enhance silkworm defenses against invasive fungi.

PubMed

Li, Youshan; Zhao, Ping; Liu, Huawei; Guo, Xiaomeng; He, Huawei; Zhu, Rui; Xiang, Zhonghuai; Xia, Qingyou

2015-02-01

Entomopathogenic fungi penetrate the insect cuticle using their abundant hydrolases. These hydrolases, which include cuticle-degrading proteases and chitinases, are important virulence factors. Our recent findings suggest that many serine protease inhibitors, especially TIL-type protease inhibitors, are involved in insect resistance to pathogenic microorganisms. To clarify the molecular mechanism underlying this resistance to entomopathogenic fungi and identify novel genes to improve the silkworm antifungal capacity, we conducted an in-depth study of serine protease inhibitors. Here, we cloned and expressed a novel silkworm TIL-type protease inhibitor, BmSPI39. In activity assays, BmSPI39 potently inhibited the virulence protease CDEP-1 of Beauveria bassiana, suggesting that it might suppress the fungal penetration of the silkworm integument by inhibiting the cuticle-degrading proteases secreted by the fungus. Phenol oxidase activation studies showed that melanization is involved in the insect immune response to fungal invasion, and that fungus-induced excessive melanization is suppressed by BmSPI39 by inhibiting the fungal cuticle-degrading proteases. To better understand the mechanism involved in the inhibition of fungal virulence by protease inhibitors, their effects on the germination of B. bassiana conidia was examined. BmSPI38 and BmSPI39 significantly inhibited the germination of B. bassiana conidia. Survival assays showed that BmSPI38 and BmSPI39 markedly improved the survival rates of silkworms, and can therefore be used as targeted resistance proteins in the silkworm. These results provided new insight into the molecular mechanisms whereby insect protease inhibitors confer resistance against entomopathogenic fungi, suggesting their potential application in medicinal or agricultural fields. Copyright © 2014 Elsevier Ltd. All rights reserved.

Oak wilt: a potential threat to southern and western oak forests

Treesearch

A. Dan Wilson

2001-01-01

Oak wilt is recognized as one of the most destructive diseases to afflict oak species in the United States. The distribution and development of oak wilt in our eastern and midwestern oak forests has been closely linked to changes in forest stand composition, forest management practices, and pathogen dissemination facilitated by human and vector activity. The potential...

Oak Wilt

Treesearch

Charles O. Rexrode; Daniel Brown

1983-01-01

Oak wilt, caused by the fungus Ceratocystis fagacearum (Bretz) Hunt, kills oak trees. It has been found in 21 States, with considerable damage occurring in the Midwest. It was first recognized as an important disease in 1944 in Wisconsin where, in localized areas (less than 100 acres (40.4 ha)), over half the oaks have been killed. Surveys in eight Wisconsin counties...

Molecular cloning, characterization and expression analysis of ATG1 in the silkworm, Bombyx mori.

PubMed

Casati, Barbara; Terova, Genciana; Cattaneo, Anna Giulia; Rimoldi, Simona; Franzetti, Eleonora; de Eguileor, Magda; Tettamanti, Gianluca

2012-12-15

Atg1 is a Serine/Threonine protein kinase that plays a pivotal role in autophagy. A complete coding sequence of ATG1 is not available for the silkworm, Bombyx mori which is a good model for studying the autophagic process. In the present study we isolated two full-length cDNAs of 2175 (transcript variant A) and 2271 (transcript variant B) bases representing ATG1 in the silkworm. Phylogenetic analysis indicated that BmATG1 was closely related to orthologs of other insects. The encoded BmAtg1 proteins shared extensive homology with orthologs from yeast to mammals, showing high conservation at the N-terminal region where the catalytic domain and ATP- and Mg-binding sites are located. A de novo prediction of the three-dimensional structure for each protein is presented. We used real-time RT-PCR to quantify dynamic changes in mRNA copy number of BmATG1 in the midgut and fat body of fifth instar larvae undergoing starvation, as well as in other tissues of silkworm at the end of last larval instar. Our qPCR results revealed that BmATG1 expression levels at the end of larval life were comparable in the midgut, fat body and Malpighian tubules, while these were higher in the gonads; moreover, the mRNA copy number of ATG1 was very different among the anterior, middle and posterior silk glands. Real-time PCR analysis also showed that starvation significantly influenced BmATG1 mRNA copy number in the fat body of silkworm, inducing an upregulation 24h after food withdrawal, with only a slight effect in the midgut. Low expression levels of BmATG1 were observed in both tissues of control animals up to the second day of spinning phase. Copyright © 2012 Elsevier B.V. All rights reserved.

Variation in flood tolerance of container-grown seedlings of swamp white oak, bur oak, and white oak

Treesearch

Michael P. Walsh; J.W. Van Sambeek; Mark V. Coggeshall

2008-01-01

How much variation in flood tolerance exists among seedlings within oak species, given the flood frequency of sites from which acorns are collected, has been largely unexplored. Our studies examined initial growth and flood tolerance for seedlings of swamp white oak (Quercus bicolor Willd.), bur oak (Q. macrocarpa L.), and white...

Oak Growth and Response to Thinning

Treesearch

Stephen R. Shifley

2004-01-01

Oak growth and yield is simultaneously influenced by tree-, stand-, and landscape-scale factors. At the tree scale oak diameter growth varies by tree species (typically n. red oak >= scarlet oak > black oak > white oak > chestnut oak > chinkapin oak > post oak), but oak diameter growth is even more strongly influenced by crown class. Oak stands go...

Oak mortality associated with crown dieback and oak borer attack in the Ozark Highlands

Treesearch

Zhaofei Fan; John M. Kabrick; Martin A. Spetich; Stephen R. Shifley; Randy G. Jensen

2008-01-01

Oak decline and related mortality have periodically plagued upland oak-hickory forests, particularly oak species in the red oak group, across the Ozark Highlands of Missouri, Arkansas and Oklahoma since the late 1970s. Advanced tree age and periodic drought, as well as Armillaria root fungi and oak borer attack are believed to contribute to oak decline and mortality....

Bombyx mori cyclin-dependent kinase inhibitor is involved in regulation of the silkworm cell cycle.

PubMed

Tang, X-F; Zhou, X-L; Zhang, Q; Chen, P; Lu, C; Pan, M-H

2018-06-01

Cyclin-dependent kinase inhibitors (CKIs) are negative regulators of the cell cycle. They can bind to cyclin-dependent kinase (CDK)-cyclin complexes and inhibit CDK activities. We identified a single homologous gene of the CDK interacting protein/kinase inhibitory protein (Cip/Kip) family, BmCKI, in the silkworm, Bombyx mori. The gene transcribes two splice variants: a 654-bp-long BmCKI-L (the longer splice variant) encoding a protein with 217 amino acids and a 579-bp-long BmCKI-S (the shorter splice variant) encoding a protein with 192 amino acids. BmCKI-L and BmCKI-S contain the Cip/Kip family conserved cyclin-binding domain and the CDK-binding domain. They are localized in the nucleus and have an unconventional bipartite nuclear localization signal at amino acid residues 181-210. Overexpression of BmCKI-L or BmCKI-S affected cell cycle progression; the cell cycle was arrested in the first gap phase of cell cycle (G1). RNA interference of BmCKI-L or BmCKI-S led to cells accumulating in the second gap phase and the mitotic phase of cell cycle (G2/M). Both BmCKI-L and BmCKI-S are involved in cell cycle regulation and probably have similar effects. The transgenic silkworm with BmCKI-L overexpression (BmCKI-L-OE), exhibited embryonic lethal, larva developmental retardation and lethal phenotypes. These results suggest that BmCKI-L might regulate the growth and development of silkworm. These findings clarify the function of CKIs and increase our understanding of cell cycle regulation in the silkworm. © 2018 The Royal Entomological Society.

Induced Hyperproteinemia and Its Effects on the Remodeling of Fat Bodies in Silkworm, Bombyx mori

PubMed Central

Chen, Xue-Dong; Wang, Yong-Feng; Wang, Yu-Long; Li, Qiu-Ying; Ma, Huan-Yu; Wang, Lu; Sima, Yang-Hu; Xu, Shi-Qing

2018-01-01

Hyperproteinemia, which is characterized by an abnormally elevated plasma protein concentration (PPC), is a high-mortality, metabolic complication associated with severe liver and kidney disease. It is difficult to clinically distinguish the difference between the impacts of primary diseases and hyperproteinemia on tissues and organs, and there are no available animal models of hyperproteinemia. Here, we constructed an animal model of hyperproteinemia with a controllable PPC and no primary disease effects in the silkworm Bombyx mori that has attracted interest owing to its potential use in the pathological analysis of model animals. Silkworm have an open circulatory system in which each organ is directly immersed in hemolymph. The fat body (FB) of a silkworm, as a major organ for nutrient storage and energy metabolism, can effectively reflect hyperproteinemia-induced metabolic abnormalities in damaged visceral tissues. A pathogenesis study showed that hyperproteinemia attenuated cell autophagy and apoptosis by attenuating an endocrine hormone, thereby preventing FB remodeling during metamorphosis. Meanwhile, hyperproteinemia increased oxidative stress in the FB and resulted in a dysfunction of amino acid conversion. Supplementation with exogenous 20-hydroxyecdysone effectively mitigated the hyperproteinemia-mediated inhibition of FB remodeling. PMID:29651251

Oak mortality associated with crown dieback and oak borer attack in the Ozark Highlands

Treesearch

Zhaofei Fan; John M. Kabrick; Martin A. Spetich; Stephen R. Shifley; Randy G. Jensen

2008-01-01

Oak decline and related mortality have periodically plagued upland oak–hickory forests, particularly oak species in the red oak group, across the Ozark Highlands of Missouri, Arkansas and Oklahoma since the late 1970s. Advanced tree age and periodic drought, as well as Armillaria root fungi and oak borer attack are believed to contribute to oak decline and mortality....

An efficient strategy for producing a stable, replaceable, highly efficient transgene expression system in silkworm, Bombyx mori

PubMed Central

Long, Dingpei; Lu, Weijian; Zhang, Yuli; Bi, Lihui; Xiang, Zhonghuai; Zhao, Aichun

2015-01-01

We developed an efficient strategy that combines a method for the post-integration elimination of all transposon sequences, a site-specific recombination system, and an optimized fibroin H-chain expression system to produce a stable, replaceable, highly efficient transgene expression system in the silkworm (Bombyx mori) that overcomes the disadvantages of random insertion and post-integration instability of transposons. Here, we generated four different transgenic silkworm strains, and of one the transgenic strains, designated TS1-RgG2, with up to 16% (w/w) of the target protein in the cocoons, was selected. The subsequent elimination of all the transposon sequences from TS1-RgG2 was completed by the heat-shock-induced expression of the transposase in vivo. The resulting transgenic silkworm strain was designated TS3-g2 and contained only the attP-flanked optimized fibroin H-chain expression cassette in its genome. A phiC31/att-system-based recombinase-mediated cassette exchange (RMCE) method could be used to integrate other genes of interest into the same genome locus between the attP sites in TS3-g2. Controlling for position effects with phiC31-mediated RMCE will also allow the optimization of exogenous protein expression and fine gene function analyses in the silkworm. The strategy developed here is also applicable to other lepidopteran insects, to improve the ecological safety of transgenic strains in biocontrol programs. PMID:25739894

Comprehensive profiling of lysine acetylation suggests the widespread function is regulated by protein acetylation in the silkworm, Bombyx mori.

PubMed

Nie, Zuoming; Zhu, Honglin; Zhou, Yong; Wu, Chengcheng; Liu, Yue; Sheng, Qing; Lv, Zhengbing; Zhang, Wenping; Yu, Wei; Jiang, Caiying; Xie, Longfei; Zhang, Yaozhou; Yao, Juming

2015-09-01

Lysine acetylation in proteins is a dynamic and reversible PTM and plays an important role in diverse cellular processes. In this study, using lysine-acetylation (Kac) peptide enrichment coupled with nano HPLC/MS/MS, we initially identified the acetylome in the silkworms. Overall, a total of 342 acetylated proteins with 667 Kac sites were identified in silkworm. Sequence motifs analysis around Kac sites revealed an enrichment of Y, F, and H in the +1 position, and F was also enriched in the +2 and -2 positions, indicating the presences of preferred amino acids around Kac sites in the silkworm. Functional analysis showed the acetylated proteins were primarily involved in some specific biological processes. Furthermore, lots of nutrient-storage proteins, such as apolipophorin, vitellogenin, storage proteins, and 30 K proteins, were highly acetylated, indicating lysine acetylation may represent a common regulatory mechanism of nutrient utilization in the silkworm. Interestingly, Ser2 proteins, the coating proteins of larval silk, were found to contain many Kac sites, suggesting lysine acetylation may be involved in the regulation of larval silk synthesis. This study is the first to identify the acetylome in a lepidoptera insect, and expands greatly the catalog of lysine acetylation substrates and sites in insects. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Sulfuryl fluoride fumigation of red oak logs eradicates the oak wilt fungus

Treesearch

Elmer L. Schmidt; Jennifer Juzwik; Brian Schneider

1997-01-01

Preliminary field trials using red oak logs from trees dying from oak wilt disease were successful in eliminating oak wilt fungus from sapwood after fumigation with sulfuryl fluoride for 72 h under tarp. These results support earlier laboratory data on the fungitoxicity of sulfuryl fluoride as a potential replacement for methyl bromide of exported red oak veneer logs....

Oak wilt and oak decline in the upper midwest USA

Treesearch

Jennifer Juzwik; Thomas L. Schmidt

2000-01-01

Oaks are a significant component of the hardwood forests of the Upper Midwest USA. Numerous species occur over vast areas in the region and are highly valued for a variety of reasons. Oak wilt caused by C. fagacearum, and oak decline associated with several factors are the major causes of the species, deterioration and death in the region....

Role of cholesterol 10-methyl group and effect of "extra" 14-methyl group on silkworm growth and development.

PubMed

Mamiya, M; Takahashi, K; Eguchi, S; Morisaki, M

1989-07-01

In order to establish the functional importance of the 10-methyl group of cholesterol and the planarity of the steroid ring, silkworms (Bombyx mori) were reared on an artificial diet containing 19-norcholesterol (1), 14 alpha-methylcholesterol (3) or 19,19-difluorocholesterol (2). The former two sterols (1 and 3) only partially satisfied the silkworm sterol requirement; growth and development were seriously retarded. The fluorinated sterol (2) was much more deleterious and was totally inadequate in meeting the sterol requirement.

Insect damage to oaks

Treesearch

Charles O. Rexrode

1971-01-01

In terms of mortality caused by insects, defoliators are the most serious enemies of oaks at the present time. An oak leaf tier, Croesia semipurprana, is one of the principal defoliators of trees in the red oak group. Oak leaf rollers, primarily Archips semiferana, have been responsible for widespread mortality in white and...

Response of white oak and black oak seedlings to a mid-story removal

Treesearch

Dylan N. Dillaway; Jeff Stringer

2005-01-01

White oak (Quercus alba L.) and black oak (Quercus velutina Lam.) often dominate stands on intermediate to high quality sites. In these stands there is often a bank of advanced oak regeneration (>1 ft. tall) in place. However, this advanced oak regeneration rarely achieves a co-dominant or dominant status when a regeneration...

Effects of BmCPV Infection on Silkworm Bombyx mori Intestinal Bacteria

PubMed Central

Zhang, Hao; Kumar, Dhiraj; Liu, Bo; Gong, Yongchang; Zhu, Min; Zhu, Liyuan; Liang, Zi; Kuang, Sulan; Chen, Fei; Hu, Xiaolong; Cao, Guangli; Xue, Renyu; Gong, Chengliang

2016-01-01

The gut microbiota has a crucial role in the growth, development and environmental adaptation in the host insect. The objective of our work was to investigate the microbiota of the healthy silkworm Bombyx mori gut and changes after the infection of B. mori cypovirus (BmCPV). Intestinal contents of the infected and healthy larvae of B. mori of fifth instar were collected at 24, 72 and 144 h post infection with BmCPV. The gut bacteria were analyzed by pyrosequencing of the 16S rRNA gene. 147(135) and 113(103) genera were found in the gut content of the healthy control female (male) larvae and BmCPV-infected female (male) larvae, respectively. In general, the microbial communities in the gut content of healthy larvae were dominated by Enterococcus, Delftia, Pelomonas, Ralstonia and Staphylococcus, however the abundance change of each genus was depended on the developmental stage and gender. Microbial diversity reached minimum at 144 h of fifth instar larvae. The abundance of Enterococcus in the females was substantially lower and the abundance of Delftia, Aurantimonas and Staphylococcus was substantially higher compared to the males. Bacterial diversity in the intestinal contents decreased after post infection with BmCPV, whereas the abundance of both Enterococcus and Staphylococcus which belongs to Gram-positive were increased. Therefore, our findings suggested that observed changes in relative abundance was related to the immune response of silkworm to BmCPV infection. Relevance analysis of plenty of the predominant genera showed the abundance of the Enterococcus genus was in negative correlation with the abundance of the most predominant genera. These results provided insight into the relationship between the gut microbiota and development of the BmCPV-infected silkworm. PMID:26745627

Effects of BmCPV Infection on Silkworm Bombyx mori Intestinal Bacteria.

PubMed

Sun, Zhenli; Lu, Yahong; Zhang, Hao; Kumar, Dhiraj; Liu, Bo; Gong, Yongchang; Zhu, Min; Zhu, Liyuan; Liang, Zi; Kuang, Sulan; Chen, Fei; Hu, Xiaolong; Cao, Guangli; Xue, Renyu; Gong, Chengliang

2016-01-01

The gut microbiota has a crucial role in the growth, development and environmental adaptation in the host insect. The objective of our work was to investigate the microbiota of the healthy silkworm Bombyx mori gut and changes after the infection of B. mori cypovirus (BmCPV). Intestinal contents of the infected and healthy larvae of B. mori of fifth instar were collected at 24, 72 and 144 h post infection with BmCPV. The gut bacteria were analyzed by pyrosequencing of the 16S rRNA gene. 147(135) and 113(103) genera were found in the gut content of the healthy control female (male) larvae and BmCPV-infected female (male) larvae, respectively. In general, the microbial communities in the gut content of healthy larvae were dominated by Enterococcus, Delftia, Pelomonas, Ralstonia and Staphylococcus, however the abundance change of each genus was depended on the developmental stage and gender. Microbial diversity reached minimum at 144 h of fifth instar larvae. The abundance of Enterococcus in the females was substantially lower and the abundance of Delftia, Aurantimonas and Staphylococcus was substantially higher compared to the males. Bacterial diversity in the intestinal contents decreased after post infection with BmCPV, whereas the abundance of both Enterococcus and Staphylococcus which belongs to Gram-positive were increased. Therefore, our findings suggested that observed changes in relative abundance was related to the immune response of silkworm to BmCPV infection. Relevance analysis of plenty of the predominant genera showed the abundance of the Enterococcus genus was in negative correlation with the abundance of the most predominant genera. These results provided insight into the relationship between the gut microbiota and development of the BmCPV-infected silkworm.

Production of recombinant Bombyx mori nucleopolyhedrovirus in silkworm by intrahaemocoelic injection with invasive diaminopimelate auxotrophic Escherichia coli containing BmNPV-Bacmid.

PubMed

Sun, Jingchen; Yao, Lunguang; Yao, Ning; Xu, Hua; Jin, Pengfei; Kan, Yunchao

2010-12-01

The present study elaborates a cost-effective and transfectant-free method for generating recombinant Bombyx mori (silkworm) nucleopolyhedrovirus in silkworm larvae and pupae by injecting invasive Escherichia coli carrying BmBacmid [BmNPV (B. mori nucleopolyhedrovirus)-Bacmid] into larval haemocoel. Up to 109 PFU (plaque-forming units)/ml of infective recombinant baculovirus was generated in the silkworm by intrahaemocoelic injection with 106 DAP (diaminopimelic acid) auxotrophic and BmBacmid containing E. coli cells expressing both invasin and listeriolysin. Thus 1 ml of overnight culture of E. coli is sufficient to inject more than 2000 larvae, while DAP costing up to $1 is enough to inject about 4000 larvae. Recombinant proteins can be controlled to be expressed mainly in pupae by adjusting the injection dose, too. In this new method, many original manipulations have been eliminated, including BmBacmid preparation and the subsequent complex transfection procedures. Hence it is a time- and cost-saving means for large-scale injection of B. mori for recombinant baculovirus production in comparison with the traditional transfection methods, which may play an important role in the industrial development of the BmNPV-silkworm bioreactor.

Identification and Characterization of Novel Chitin-Binding Proteins from the Larval Cuticle of Silkworm, Bombyx mori.

PubMed

Dong, Zhaoming; Zhang, Weiwei; Zhang, Yan; Zhang, Xiaolu; Zhao, Ping; Xia, Qingyou

2016-05-06

Cuticle is mainly made of chitin filaments embedded in a matrix of cuticular proteins (CPs). Cuticular chitins have minor differences, whereas CPs are widely variable with respect to their sequences and structures. To understand the molecular basis underlying the mechanical properties of cuticle, it is necessary to know which CPs interact with chitin and how they are assembled into the cuticle structure. In the present study, a chitin-binding assay was performed followed by liquid chromatography-tandem mass spectrometry to identify the extracted proteins from the larval cuticle of silkworm, Bombyx mori. There were 463 proteins identified from the silkworm larval cuticle, 200 of which were recovered in the chitin-binding fraction. A total of 103 proteins were annotated as CPs, which were classified into 11 CP families based on their conserved motifs, including CPR, CPAP, CPT, CPF and CPFL, CPCFC, chitin_bind 3, BmCPH2 homologues, BmCPH9 homologues, BmCPG1 homologues, BmCPG20 homologues, and BmCPG21 homologues. A total of five CP families were newly identified in the chitin-binding fraction, thereby providing new information and insight into the composition, structure, and function of the silkworm larval cuticle.

Aspartate Decarboxylase is Required for a Normal Pupa Pigmentation Pattern in the Silkworm, Bombyx mori.

PubMed

Dai, Fangyin; Qiao, Liang; Cao, Cun; Liu, Xiaofan; Tong, Xiaoling; He, Songzhen; Hu, Hai; Zhang, Li; Wu, Songyuan; Tan, Duan; Xiang, Zhonghuai; Lu, Cheng

2015-06-16

The pigmentation pattern of Lepidoptera varies greatly in different development stages. To date, the effects of key genes in the melanin metabolism pathway on larval and adult body color are distinct, yet the effects on pupal pigmentation remains unclear. In the silkworm, Bombyx mori, the black pupa (bp) mutant is only specifically melanized at the pupal stage. Using positional cloning, we found that a mutation in the Aspartate decarboxylase gene (BmADC) is causative in the bp mutant. In the bp mutant, a SINE-like transposon with a length of 493 bp was detected ~2.2 kb upstream of the transcriptional start site of BmADC. This insertion causes a sharp reduction in BmADC transcript levels in bp mutants, leading to deficiency of β-alanine and N-β-alanyl dopamine (NBAD), but accumulation of dopamine. Following injection of β-alanine into bp mutants, the color pattern was reverted that of the wild-type silkworms. Additionally, melanic pupae resulting from knock-down of BmADC in the wild-type strain were obtained. These findings show that BmADC plays a crucial role in melanin metabolism and in the pigmentation pattern of the silkworm pupal stage. Finally, this study contributes to a better understanding of pupa pigmentation patterns in Lepidoptera.

Aspartate Decarboxylase is Required for a Normal Pupa Pigmentation Pattern in the Silkworm, Bombyx mori

PubMed Central

Dai, Fangyin; Qiao, Liang; Cao, Cun; Liu, Xiaofan; Tong, Xiaoling; He, Songzhen; Hu, Hai; Zhang, Li; Wu, Songyuan; Tan, Duan; Xiang, Zhonghuai; Lu, Cheng

2015-01-01

The pigmentation pattern of Lepidoptera varies greatly in different development stages. To date, the effects of key genes in the melanin metabolism pathway on larval and adult body color are distinct, yet the effects on pupal pigmentation remains unclear. In the silkworm, Bombyx mori, the black pupa (bp) mutant is only specifically melanized at the pupal stage. Using positional cloning, we found that a mutation in the Aspartate decarboxylase gene (BmADC) is causative in the bp mutant. In the bp mutant, a SINE-like transposon with a length of 493 bp was detected ~2.2 kb upstream of the transcriptional start site of BmADC. This insertion causes a sharp reduction in BmADC transcript levels in bp mutants, leading to deficiency of β-alanine and N-β-alanyl dopamine (NBAD), but accumulation of dopamine. Following injection of β-alanine into bp mutants, the color pattern was reverted that of the wild-type silkworms. Additionally, melanic pupae resulting from knock-down of BmADC in the wild-type strain were obtained. These findings show that BmADC plays a crucial role in melanin metabolism and in the pigmentation pattern of the silkworm pupal stage. Finally, this study contributes to a better understanding of pupa pigmentation patterns in Lepidoptera. PMID:26077025

Combined toxicity of chlorantraniliprole, lambda-cyhalothrin, and imidacloprid to the silkworm Bombyx mori (Lepidoptera: Bombycidae).

PubMed

Liu, Yanmei; Zhang, Hui; He, Fengmei; Li, Xuesheng; Tan, Huihua; Zeng, Dongqiang

2018-05-29

Insecticides with different modes of action may act in combination, in ways such as drifting, spray equipment residual, or utilizing concurrently in mulberry orchards or nearby agricultural fields. Silkworms may suffer from a diverse impact on the survival. In this study, the toxicity of chlorantraniliprole, lambda-cyhalothrin, and imidacloprid and their combinations to the second instar of silkworms (Bombyx mori (L.)(Lepidoptera: Bombycidae)) were evaluated after 48 and 72 h treatment by the leaf-dipping method and the combination index (CI)-isobologram equation. After 48 h treatment, results indicated that (1) the increasing order of toxicity was imidacloprid < chlorantraniliprole < lambda-cyhalothrin, and that (2) synergism was predominated in most combinations excepted for the lambda-cyhalothrin + imidacloprid combination which displayed an additive effect at f a value 0.5. Then, after 72 h treatment, results exhibited that (1) the increasing order of toxicity was imidacloprid < lambda-cyhalothrin < chlorantraniliprole, and that (2) only the chlorantraniliprole + imidacloprid mixture yielded antagonism at f a value 0.5; the other combinations performed an additive effect at least. Consequently, combined toxicity of mixtures may pose a worse effect on silkworm than single toxicity of insecticides. Therefore, we suggest that insecticide mixtures should be added into ecotoxicological risk assessment.

A discovery of novel microRNAs in the silkworm (Bombyx mori) genome.

PubMed

Yu, Xiaomin; Zhou, Qing; Cai, Yimei; Luo, Qibin; Lin, Hongbin; Hu, Songnian; Yu, Jun

2009-12-01

MicroRNAs (miRNAs) are pivotal regulators involved in various physiological and pathological processes via their post-transcriptional regulation of gene expressions. We sequenced 14 libraries of small RNAs constructed from samples spanning the life cycle of silkworms, and discovered 50 novel miRNAs previously not known in animals and verified 43 of them using stem-loop RT-PCR. Our genome-wide analyses of 27 species-specific miRNAs suggest they arise from transposable elements, protein-coding genes duplication/transposition and random foldback sequences; which is consistent with the idea that novel animal miRNAs may evolve from incomplete self-complementary transcripts and become fixed in the process of co-adaptation with their targets. Computational prediction suggests that the silkworm-specific miRNAs may have a preference of regulating genes that are related to life-cycle-associated traits, and these genes can serve as potential targets for subsequent studies of the modulating networks in the development of Bombyx mori.

Comparative transcriptome profiling of a thermal resistant vs. sensitive silkworm strain in response to high temperature under stressful humidity condition

PubMed Central

Xiao, Jinshu; Wang, La; Liu, Taihang; Wu, Yunfei; Dong, Feifan; Jiang, Yaming; Pan, Minhui; Zhang, Youhong; Lu, Cheng

2017-01-01

Thermotolerance is important particularly for poikilotherms such as insects. Understanding the mechanisms by which insects respond to high temperatures can provide insights into their adaptation to the environment. Therefore, in this study, we performed a transcriptome analysis of two silkworm strains with significantly different resistance to heat as well as humidity; the thermo-resistant strain 7532 and the thermos-sensitive strain Knobbed. We identified in total 4,944 differentially expressed genes (DEGs) using RNA-Seq. Among these, 4,390 were annotated and 554 were novel. Gene Ontology (GO) analysis of 747 DEGs identified between RT_48h (Resistant strain with high-temperature Treatment for 48 hours) and ST_48h (Sensitive strain with high-temperature Treatment for 48 hours) showed significant enrichment of 12 GO terms including metabolic process, extracellular region and serine-type peptidase activity. Moreover, we discovered 12 DEGs that may contribute to the heat-humidity stress response in the silkworm. Our data clearly showed that 48h post-exposure may be a critical time point for silkworm to respond to high temperature and humidity. These results provide insights into the genes and biological processes involved in high temperature and humidity tolerance in the silkworm, and advance our understanding of thermal tolerance in insects. PMID:28542312

Comparative transcriptome profiling of a thermal resistant vs. sensitive silkworm strain in response to high temperature under stressful humidity condition.

PubMed

Xiao, Wenfu; Chen, Peng; Xiao, Jinshu; Wang, La; Liu, Taihang; Wu, Yunfei; Dong, Feifan; Jiang, Yaming; Pan, Minhui; Zhang, Youhong; Lu, Cheng

2017-01-01

Thermotolerance is important particularly for poikilotherms such as insects. Understanding the mechanisms by which insects respond to high temperatures can provide insights into their adaptation to the environment. Therefore, in this study, we performed a transcriptome analysis of two silkworm strains with significantly different resistance to heat as well as humidity; the thermo-resistant strain 7532 and the thermos-sensitive strain Knobbed. We identified in total 4,944 differentially expressed genes (DEGs) using RNA-Seq. Among these, 4,390 were annotated and 554 were novel. Gene Ontology (GO) analysis of 747 DEGs identified between RT_48h (Resistant strain with high-temperature Treatment for 48 hours) and ST_48h (Sensitive strain with high-temperature Treatment for 48 hours) showed significant enrichment of 12 GO terms including metabolic process, extracellular region and serine-type peptidase activity. Moreover, we discovered 12 DEGs that may contribute to the heat-humidity stress response in the silkworm. Our data clearly showed that 48h post-exposure may be a critical time point for silkworm to respond to high temperature and humidity. These results provide insights into the genes and biological processes involved in high temperature and humidity tolerance in the silkworm, and advance our understanding of thermal tolerance in insects.

Reducing blood glucose levels in TIDM mice with an orally administered extract of sericin from hIGF-I-transgenic silkworm cocoons.

PubMed

Song, Zuowei; Zhang, Mengyao; Xue, Renyu; Cao, Guangli; Gong, Chengliang

2014-05-01

In previous studies, we reported that the blood glucose levels of mice with type I diabetes mellitus (TIDM) was reduced with orally administered silk gland powder from silkworms transgenic for human insulin-like growth factor-I (hIGF-I). However, potential safety hazards could not be eliminated because the transgenic silk gland powder contained heterologous DNA, including the green fluorescent protein (gfp) and neomycin resistance (neo) genes. These shortcomings might be overcome if the recombinant hIGF-I were secreted into the sericin layer of the cocoon. In this study, silkworm eggs were transfected with a novel piggyBac transposon vector, pigA3GFP-serHS-hIGF-I-neo, containing the neo, gfp, and hIGF-I genes controlled by the sericin-1 (ser-1) promoter with the signal peptide DNA sequence of the fibrin heavy chain (Fib-H) and a helper plasmid containing the piggyBac transposase sequence under the control of the Bombyx mori actin 3 (A3) promoter, using sperm-mediated gene transfer to generate the transformed silkworms. The hIGF-I content estimated by enzyme-linked immunosorbent assay was approximately 162.7 ng/g. To estimate the biological activity of the expressed hIGF-I, streptozotocin-induced TIDM mice were orally administered sericin from the transgenic silkworm. The blood glucose levels of the mice were significantly reduced, suggesting that the extract from the transgenic hIGF-I silkworm cocoons can be used as an orally administered drug. Copyright © 2014 Elsevier Ltd. All rights reserved.

Impacts on silkworm larvae midgut proteomics by transgenic Trichoderma strain and analysis of glutathione S-transferase sigma 2 gene essential for anti-stress response of silkworm larvae.

PubMed

Li, Yingying; Dou, Kai; Gao, Shigang; Sun, Jianan; Wang, Meng; Fu, Kehe; Yu, Chuanjin; Wu, Qiong; Li, Yaqian; Chen, Jie

2015-08-03

Lepidoptera is a large order of insects that have major impacts on humans as agriculture pests. The midgut is considered an important target for insect control. In the present study, 10 up-regulated, 18 down-regulated, and one newly emerged protein were identified in the transgenic Trichoderma-treated midgut proteome. Proteins related to stress response, biosynthetic process, and metabolism process were further characterized through quantitative real-time PCR (qPCR). Of all the identified proteins, the glutathione S-transferase sigma 2 (GSTs2) gene displayed enhanced expression when larvae were fed with Trichoderma wild-type or transgenic strains. Down regulation of GSTs2 expression by RNA interference (RNAi) resulted in inhibition of silkworm growth when larvae were fed with mulberry leaves treated with the transgenic Trichoderma strain. Weight per larva decreased by 18.2%, 11.9%, and 10.7% in the untreated control, ddH2O, and GFP dsRNA groups, respectively, at 24h, while the weight decrease was higher at 42.4%, 28.8% and 32.4% at 72 h after treatment. Expression of glutathione S-transferase omega 2 (GSTo2) was also enhanced when larvae were fed with mulberry leaves treated with the transgenic Trichoderma strain. These results indicated that there was indeed correlation between enhanced expression of GSTs2 and the anti-stress response of silkworm larvae against Trichoderma. This study represents the first attempt at understanding the effects of transgenic organisms on the midgut proteomic changes in silkworm larvae. Our findings could not only broaden the biological control targets of insect at the molecular level, but also provide a theoretical foundation for biological safety evaluation of the transgenic Trichoderma strain. Copyright © 2015 Elsevier B.V. All rights reserved.

Bioengineered silkworms with butterfly cytotoxin-modified silk glands produce sericin cocoons with a utility for a new biomaterial.

PubMed

Otsuki, Ryosuke; Yamamoto, Masafumi; Matsumoto, Erika; Iwamoto, Shin-Ichi; Sezutsu, Hideki; Suzui, Masumi; Takaki, Keiko; Wakabayashi, Keiji; Mori, Hajime; Kotani, Eiji

2017-06-27

Genetically manipulated organisms with dysfunction of specific tissues are crucial for the study of various biological applications and mechanisms. However, the bioengineering of model organisms with tissue-specific dysfunction has not progressed because the challenges of expression of proteins, such as cytotoxins, in living cells of individual organisms need to be overcome first. Here, we report the establishment of a transgenic silkworm ( Bombyx mori ) with posterior silk glands (PSGs) that was designed to express the cabbage butterfly ( Pieris rapae ) cytotoxin pierisin-1A (P1A). P1A, a homolog of the apoptosis inducer pierisin-1, had relatively lower DNA ADP ribosyltransferase activity than pierisin-1; it also induced the repression of certain protein synthesis when expressed in B. mori -derived cultured cells. The transgene-derived P1A domain harboring enzymatic activity was successfully expressed in the transgenic silkworm PSGs. The glands showed no apoptosis-related morphological changes; however, an abnormal appearance was evident. The introduced truncated P1A resulted in the dysfunction of PSGs in that they failed to produce the silk protein fibroin. Cocoons generated by the silkworms solely consisted of the glue-like glycoprotein sericin, from which soluble sericin could be prepared to form hydrogels. Embryonic stem cells could be maintained on the hydrogels in an undifferentiated state and proliferated through stimulation by the cytokines introduced into the hydrogels. Thus, bioengineering with targeted P1A expression successfully produced silkworms with a biologically useful trait that has significant application potential.

Effects of added CeCl3 on resistance of fifth-instar larvae of silkworm to Bombyx mori nucleopolyhedrovirus infection.

PubMed

Li, Bing; Xie, Yi; Cheng, Zhe; Cheng, Jie; Hu, Rengping; Cui, Yaling; Gong, Xiaolan; Shen, Weide; Hong, Fashui

2012-06-01

One of the most important agents causing lethal disease in the silkworm is the Bombyx mori nucleopolyhedrovirus (BmNPV), while low-dose rare earths are demonstrated to increase immune capacity in animals. However, very little is known about the effects of added CeCl(3) on decreasing BmNPV infection of silkworm. The present study investigated the effects of added CeCl(3) to an artificial diet on resistance of fifth-instar larvae of silkworm to BmNPV infection. Our findings indicated that added CeCl(3) significantly decreased inhibition of growth and mortality of fifth-instar larvae caused by BmNPV infection. Furthermore, the added CeCl(3) obviously decreased lipid peroxidation level and accumulation of reactive oxygen species such as O(2)(-), H(2)O(2), (·)OH, and NO and increased activities of the antioxidant enzymes including superoxide dismutase, catalase, ascorbate peroxidase, glutathione peroxidase, ascorbate, and glutathione contents in the BmNPV-infected fifth-instar larvae. In addition, the added CeCl(3) could significantly promote acetylcholine esterase activity and attenuate the activity of inducible nitric oxide synthase in the BmNPV-infected fifth-instar larvae. These findings suggested that added CeCl(3) may relieve oxidative damage and neurotoxicity of silkworm caused by BmNPV infection via increasing antioxidant capacity and acetylcholine esterase activity.

Conceptual design of a bioregenerative life support system containing crops and silkworms

NASA Astrophysics Data System (ADS)

Hu, Enzhu; Bartsev, Sergey I.; Liu, Hong

2010-04-01

This article summarizes a conceptual design of a bioregenerative life support system for permanent lunar base or planetary exploration. The system consists of seven compartments - higher plants cultivation, animal rearing, human habitation, water recovery, waste treatment, atmosphere management, and storages. Fifteen kinds of crops, such as wheat, rice, soybean, lettuce, and mulberry, were selected as main life support contributors to provide the crew with air, water, and vegetable food. Silkworms fed by crop leaves were designated to produce partial animal nutrition for the crew. Various physical-chemical and biological methods were combined to reclaim wastewater and solid waste. Condensate collected from atmosphere was recycled into potable water through granular activated carbon adsorption, iodine sterilization, and trace element supplementation. All grey water was also purified though multifiltration and ultraviolet sterilization. Plant residue, human excrement, silkworm feces, etc. were decomposed into inorganic substances which were finally absorbed by higher plants. Some meat, ingredients, as well as nitrogen fertilizer were prestored and resupplied periodically. Meanwhile, the same amount and chemical composition of organic waste was dumped to maintain the steady state of the system. A nutritional balanced diet was developed by means of the linear programming method. It could provide 2721 kcal of energy, 375.5 g of carbohydrate, 99.47 g of protein, and 91.19 g of fat per capita per day. Silkworm powder covered 12.54% of total animal protein intakes. The balance of material flows between compartments was described by the system of stoichiometric equations. Basic life support requirements for crews including oxygen, food, potable and hygiene water summed up to 29.68 kg per capita per day. The coefficient of system material closure reached 99.40%.

People and oaks

Treesearch

Paul F. Starrs

2015-01-01

While technical knowledge of oaks, acorns, habitat, wildlife, and woodland environments is evolving and a sought-after field of study, there are profound linkages, at once humanistic and artistic, where it comes to people and oaks. Looking at six distinct facets of humans and oak woodlands, this essay suggests that the bonds of people to place can be mediated by the...

Development of advanced antimicrobial and sterilized plasma polypropylene grafted muga (Antheraea assama) silk as suture biomaterial.

PubMed

Gogoi, Dolly; Choudhury, Arup Jyoti; Chutia, Joyanti; Pal, Arup Ratan; Khan, Mojibur; Choudhury, Manash; Pathak, Pallabi; Das, Gouranga; Patil, Dinkar S

2014-04-01

Surface modification of silk fibroin (SF) materials using environmentally friendly and non-hazardous process to tailor them for specific application as biomaterials has drawn a great deal of interest in the field of biomedical research. To further explore this area of research, in this report, polypropylene (PP) grafted muga (Antheraea assama) SF (PP-AASF) suture is developed using plasma treatment and plasma graft polymerization process. For this purpose, AASF is first sterilized in argon (Ar) plasma treatment followed by grafting PP onto its surface. AASF is a non-mulberry variety having superior qualities to mulberry SF and is still unexplored in the context of suture biomaterial. AASF, Ar plasma treated AASF (AASFAr) and PP-AASF are subjected to various characterization techniques for better comparison and the results are attempted to correlate with their observed properties. Excellent mechanical strength, hydrophobicity, antibacterial behavior, and remarkable wound healing activity of PP-AASF over AASF and AASFAr make it a promising candidate for application as sterilized suture biomaterial. Copyright © 2013 Wiley Periodicals, Inc.

GC/MS-based metabolomic studies reveal key roles of glycine in regulating silk synthesis in silkworm, Bombyx mori.

PubMed

Chen, Quanmei; Liu, Xinyu; Zhao, Ping; Sun, Yanhui; Zhao, Xinjie; Xiong, Ying; Xu, Guowang; Xia, Qingyou

2015-02-01

Metabolic profiling of silkworm, especially the factors that affect silk synthesis at the metabolic level, is little known. Herein, metabolomic method based on gas chromatography-mass spectrometry was applied to identify key metabolic changes in silk synthesis deficient silkworms. Forty-six differential metabolites were identified in Nd group with the defect of silk synthesis. Significant changes in the levels of glycine and uric acid (up-regulation), carbohydrates and free fatty acids (down-regulation) were observed. The further metabolomics of silk synthesis deficient silkworms by decreasing silk proteins synthesis using knocking out fibroin heavy chain gene or extirpating silk glands operation showed that the changes of the metabolites were almost consistent with those of the Nd group. Furthermore, the increased silk yields by supplying more glycine or its related metabolite confirmed that glycine is a key metabolite to regulate silk synthesis. These findings provide important insights into the regulation between metabolic profiling and silk synthesis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Microwave-assisted extraction of silkworm pupal oil and evaluation of its fatty acid composition, physicochemical properties and antioxidant activities.

PubMed

Hu, Bin; Li, Cheng; Zhang, Zhiqing; Zhao, Qing; Zhu, Yadong; Su, Zhao; Chen, Yizi

2017-09-15

Microwave-assisted extraction (MAE) of oil from silkworm pupae was firstly performed in the present research. The response surface methodology was applied to optimize the parameters for MAE. The yield of oil by MAE was 30.16% under optimal conditions of a mixed solvent consisting of ethanol and n-hexane (1:1, v/v), microwave power (360W), liquid to solid ratio (7.5/1mL/g), microwave time (29min). Moreover, oil extracted by MAE was quantitatively (yield) and qualitatively (fatty acid profile) similar to those obtained using Soxhlet extraction (SE), but oil extracted by MAE exhibited favourable physicochemical properties and oxidation stability. Additionally, oil extracted by MAE had a higher content of total phenolic, and it showed stronger antioxidant activities. Scanning electron microscopy revealed that microwave technique efficiently promoted the release of oil by breaking down the cell structure of silkworm pupae. Therefore, MAE can be an effective method for the silkworm pupal oil extraction. Copyright © 2017 Elsevier Ltd. All rights reserved.

Osiris9a is a major component of silk fiber in lepidopteran insects.

PubMed

Liu, Chun; Hu, Wenbo; Cheng, Tingcai; Peng, Zhangchuan; Mita, Kazuei; Xia, Qingyou

2017-10-01

In a previous high-throughput proteomics study, it was found that the silkworm cocoon contains hundreds of complex proteins, many of which have unknown functions, in addition to fibroins, sericins, and some protease inhibitors. Osiris was one of the proteins with no known function. In this study, we identified the Osiris gene family members and constructed a phylogenetic tree based on the sequences from different species. Our results indicate that the Osiris9 gene subfamily contains six members; it is specifically expressed in lepidopteran insects and has evolved by gene duplication. An Osiris gene family member from Bombyx mori was designated as BmOsiris9a (BmOsi9a) on the basis of its homology to Drosophila melanogaster Osiris9. The expression pattern of BmOsi9a showed that it was highly expressed only in the middle silk gland of silkworm larvae, similar to Sericin1 (Ser1). BmOsi9a was visualized as two bands in western blot analysis, implying that it probably undergoes post-translational modifications. Immunohistochemistry analysis revealed that BmOsi9a was synthesized and secreted into the lumen of the middle silk gland, and was localized in the sericin layer in the silk fiber. BmOsi9a was found in the silk fibers of not only three Bombycidae species, viz. B. mori, B. mandarina, and B. huttoni, but also in the fibers collected from Saturniidae species, including Antheraea assama, Antheraea mylitta, and Samia cynthia. Although the exact biological function of Osi9a in the silk fibers is unknown, our results are important because they demonstrate that Osi9a is a common structural component of silk fiber and is expressed widely among the silk-producing Bombycidae and Saturniidae insects. Our results should help in understanding the role of Osi9a in silk fibers. Copyright © 2017 Elsevier Ltd. All rights reserved.

Great oaks from little acorns grow: planting native oak in the Pacific Northwest

Treesearch

Gail Wells; Warren Devine; Connie Harrington

2010-01-01

The decline of oak woodlands is an urgent conservation challenge in the Pacific Northwest. Prior to settlement by Euro-Americans, prairies, oak-dominated savannas, and oak woodlands were abundant in the low-lying areas of the region. Now it’s estimated that 1 to 5 percent of that native oak savanna remains. The rest has been supplanted by pastures, fields, Douglas-fir...

Red Oak Borer

Treesearch

D. E. Donley; R.E. Acciavatti

1980-01-01

The red oak borer, Enaphalodes rufulus (Haldeman)3, is an important member of the oak borer complex that permanently damages the wood of living oak trees and causes a decrease in lumber grade. The loss in grade can amount to 40 percent of the current tree value, which, at today's prices, is about $80 per thousand board feet for factory grade lumber in terms of...

Experimental RNomics and genomic comparative analysis reveal a large group of species-specific small non-message RNAs in the silkworm Bombyx mori

PubMed Central

Li, Dandan; Wang, Yanhong; Zhang, Kun; Jiao, Zhujin; Zhu, Xiaopeng; Skogerboe, Geir; Guo, Xiangqian; Chinnusamy, Viswanathan; Bi, Lijun; Huang, Yongping; Dong, Shuanglin; Chen, Runsheng; Kan, Yunchao

2011-01-01

Accumulating evidences show that small non-protein coding RNAs (ncRNAs) play important roles in development, stress response and other cellular processes. The silkworm is an important model for studies on insect genetics and control of lepidopterous pests. Here, we have performed the first systematic identification and analysis of intermediate size ncRNAs (50–500 nt) in the silkworm. We identified 189 novel ncRNAs, including 141 snoRNAs, six snRNAs, three tRNAs, one SRP and 38 unclassified ncRNAs. Forty ncRNAs showed significantly altered expression during silkworm development or across specific stage transitions. Genomic comparisons revealed that 123 of these ncRNAs are potentially silkworm-specific. Analysis of the genomic organization of the ncRNA loci showed that 32.62% of the novel snoRNA loci are intergenic, and that all the intronic snoRNAs follow the pattern of one-snoRNA-per-intron. Target site analysis predicted a total of 95 2′-O-methylation and pseudouridylation modification sites of rRNAs, snRNAs and tRNAs. Together, these findings provide new clues for future functional study of ncRNA during insect development and evolution. PMID:21227919

Risk analysis and guidelines for harvest activities in wisconsin oak timberlands to minimize oak wilt threat

Treesearch

Jennifer Juzwik; Jane Cummings-Carlson; Kyoko Scanlon

2010-01-01

Oaks (Quercus spp.) are an important species group in the forests of Wisconsin. The State’s timberland typed as oak-hickory forest was estimated at 2.9 million acres in 1996. Growing stock volume for red oak was estimated at 2.4 billion cubic feet, whereas select white oak volume was estimated to be 927 million cubic feet. Oak wilt, the oak disease...

Antheraea pernyi (Lepidoptera: Saturniidae) and Its Importance in Sericulture, Food Consumption, and Traditional Chinese Medicine.

PubMed

Li, Wenli; Zhang, Zhengyao; Lin, Lan; Terenius, Olle

2017-08-01

Sericulture was developed in China in ancient times. Antheraea pernyi Guérin-Méneville was domesticated at least 2,000 yr ago, and Chinese farmers developed artificial rearing of A. pernyi before the 17th century. Today, >60,000 tons of cocoons are produced in China each year, which accounts for 90% of the world production. Despite the widespread utilization of A. pernyi in China and a long history of domestic research, the knowledge of A. pernyi outside China is limited. Therefore, we have in this paper summarized the production, usage, and breeding of A. pernyi. The foremost usage of A. pernyi is as silk producers; however, about 55-70% is used for other purposes. In this paper, we give examples of how the different developmental stages are used as a food source for human consumption and in traditional Chinese medicine, both directly in different preparations and also as a nutrient source for rearing medicinal fungi. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Silvical characteristics of the five upland oaks

Treesearch

Earl L. Core

1971-01-01

The five most important upland oaks of eastern North America are white oak (Quercus alba), chestnut oak (Q. prinus), northern red oak (Q. rubra), black oak (Q. velutina), and scarlet oak (Q. coccinea). Of these, white oak and northern red oak are most characteristic of...

Thromboelastometric and platelet responses to silk biomaterials.

PubMed

Kundu, Banani; Schlimp, Christoph J; Nürnberger, Sylvia; Redl, Heinz; Kundu, S C

2014-05-13

Silkworm's silk is natural biopolymer with unique properties including mechanical robustness, all aqueous base processing and ease in fabrication into different multifunctional templates. Additionally, the nonmulberry silks have cell adhesion promoting tri-peptide (RGD) sequences, which make it an immensely potential platform for regenerative medicine. The compatibility of nonmulberry silk with human blood is still elusive; thereby, restricts its further application as implants. The present study, therefore, evaluate the haematocompatibility of silk biomaterials in terms of platelet interaction after exposure to nonmulberry silk of Antheraea mylitta using thromboelastometry (ROTEM). The mulberry silk of Bombyx mori and clinically used Uni-Graft W biomaterial serve as references. Shortened clotting time, clot formation times as well as enhanced clot strength indicate the platelet mediated activation of blood coagulation cascade by tested biomaterials; which is comparable to controls.

Bioengineered silkworms with butterfly cytotoxin-modified silk glands produce sericin cocoons with a utility for a new biomaterial

PubMed Central

Otsuki, Ryosuke; Yamamoto, Masafumi; Matsumoto, Erika; Iwamoto, Shin-ichi; Sezutsu, Hideki; Suzui, Masumi; Takaki, Keiko; Wakabayashi, Keiji; Mori, Hajime; Kotani, Eiji

2017-01-01

Genetically manipulated organisms with dysfunction of specific tissues are crucial for the study of various biological applications and mechanisms. However, the bioengineering of model organisms with tissue-specific dysfunction has not progressed because the challenges of expression of proteins, such as cytotoxins, in living cells of individual organisms need to be overcome first. Here, we report the establishment of a transgenic silkworm (Bombyx mori) with posterior silk glands (PSGs) that was designed to express the cabbage butterfly (Pieris rapae) cytotoxin pierisin-1A (P1A). P1A, a homolog of the apoptosis inducer pierisin-1, had relatively lower DNA ADP ribosyltransferase activity than pierisin-1; it also induced the repression of certain protein synthesis when expressed in B. mori-derived cultured cells. The transgene-derived P1A domain harboring enzymatic activity was successfully expressed in the transgenic silkworm PSGs. The glands showed no apoptosis-related morphological changes; however, an abnormal appearance was evident. The introduced truncated P1A resulted in the dysfunction of PSGs in that they failed to produce the silk protein fibroin. Cocoons generated by the silkworms solely consisted of the glue-like glycoprotein sericin, from which soluble sericin could be prepared to form hydrogels. Embryonic stem cells could be maintained on the hydrogels in an undifferentiated state and proliferated through stimulation by the cytokines introduced into the hydrogels. Thus, bioengineering with targeted P1A expression successfully produced silkworms with a biologically useful trait that has significant application potential. PMID:28607081

BmRobo2/3 is required for axon guidance in the silkworm Bombyx mori.

PubMed

Li, Xiao-Tong; Yu, Qi; Zhou, Qi-Sheng; Zhao, Xiao; Liu, Zhao-Yang; Cui, Wei-Zheng; Liu, Qing-Xin

2016-02-15

Axon guidance is critical for proper wiring of the nervous system. During the neural development, the axon guidance molecules play a key role and direct axons to choose the correct way to reach the target. Robo, as the receptor of axon guidance molecule Slit, is evolutionarily conserved from planarians to humans. However, the function of Robo in the silkworm, Bombyx mori, remained unknown. In this study, we cloned robo2/3 from B. mori (Bmrobo2/3), a homologue of robo2/3 in Tribolium castaneum. Moreover, BmRobo2/3 was localized in the neuropil, and RNAi-mediated knockdown of Bmrobo2/3 resulted in the longitudinal connectives forming closer to the midline. These data demonstrate that BmRobo2/3 is required for axon guidance in the silkworm. Copyright © 2015 Elsevier B.V. All rights reserved.

Biological and molecular characterization of silkworm strains from the Brazilian germplasm bank of Bombyx mori.

PubMed

Pereira, N C; Munhoz, R E F; Bignotto, T S; Bespalhuk, R; Garay, L B; Saez, C R N; Fassina, V A; Nembri, A; Fernandez, M A

2013-06-28

Brazil has only one public genetic pool of Bombyx mori strains, which was established in 2005 at Universidade Estadual de Maringá, Maringá, Paraná State. This genetic bank has been maintained, and the strains have been characterized using genetic and morphological tools. The quantitative and qualitative traits, directly or indirectly related to productivity, were evaluated in 14 silkworm strains. In addition to biological and productivity analyses, DNA markers related to susceptibility to the B. mori nucleopolyhedrovirus (BmNPV) were analyzed. BmNPV is a major cause of production loss and is a serious problem for Paraná sericulture. The silkworm strains from diverse geographic origins were found to have different characteristics, including body weight, larval stage duration, cocoon weight, and other biological traits. In terms of productivity, the raw silk percentages were almost uniform, with an overall average of 16.28%. Overall, the Chinese strain C37 gave the best performance in many of the quantitative traits, and it surpassed the other strains in productivity traits. Therefore, it can be used as one of the strains that compose the elite germplasm for silkworm breeding programs. Additionally, genetic molecular markers were efficient in discriminating between B. mori strains that had been identified based on their geographical origin. We found that all Japanese strains produced a 400-bp molecular marker that has been associated with susceptibility to BmNPV.

Assessing Methods to Protect Susceptible Oak and Tanoak Stands from Sudden Oak Death

Treesearch

Tedmund Swiecki; Elizabeth Bernhardt

2010-01-01

Landowners and managers have been seeking ways to protect susceptible oak (Quercus) species and tanoak (Lithocarpus densiflorus) from sudden oak death (SOD) caused by Phytophthora ramorum. Because disease epidemiology differs between tanoaks and susceptible oaks, we are testing different control strategies...

Genome-Wide Transcriptional Response of Silkworm (Bombyx mori) to Infection by the Microsporidian Nosema bombycis

PubMed Central

Pan, Guoqing; Li, Zhihong; Han, Bing; Xu, Jinshan; Lan, Xiqian; Chen, Jie; Yang, Donglin; Chen, Quanmei; Sang, Qi; Ji, Xiaocun; Li, Tian; Long, Mengxian; Zhou, Zeyang

2013-01-01

Microsporidia have attracted much attention because they infect a variety of species ranging from protists to mammals, including immunocompromised patients with AIDS or cancer. Aside from the study on Nosema ceranae, few works have focused on elucidating the mechanism in host response to microsporidia infection. Nosema bombycis is a pathogen of silkworm pébrine that causes great economic losses to the silkworm industry. Detailed understanding of the host (Bombyx mori) response to infection by N. bombycis is helpful for prevention of this disease. A genome-wide survey of the gene expression profile at 2, 4, 6 and 8 days post-infection by N. bombycis was performed and results showed that 64, 244, 1,328, 1,887 genes were induced, respectively. Up to 124 genes, which are involved in basal metabolism pathways, were modulated. Notably, B. mori genes that play a role in juvenile hormone synthesis and metabolism pathways were induced, suggesting that the host may accumulate JH as a response to infection. Interestingly, N. bombycis can inhibit the silkworm serine protease cascade melanization pathway in hemolymph, which may be due to the secretion of serpins in the microsporidia. N. bombycis also induced up-regulation of several cellular immune factors, in which CTL11 has been suggested to be involved in both spore recognition and immune signal transduction. Microarray and real-time PCR analysis indicated the activation of silkworm Toll and JAK/STAT pathways. The notable up-regulation of antimicrobial peptides, including gloverins, lebocins and moricins, strongly indicated that antimicrobial peptide defense mechanisms were triggered to resist the invasive microsporidia. An analysis of N. bombycis-specific response factors suggested their important roles in anti-microsporidia defense. Overall, this study primarily provides insight into the potential molecular mechanisms for the host-parasite interaction between B. mori and N. bombycis and may provide a foundation for

Oak Dispersal Syndromes: Do Red and White Oaks Exhibit Different Dispersal Srategies?

Treesearch

Michael Steele; Peter Smallwood; William B. Terzaghi; John E. Carlson; Thomas conteras; Amy McEuen

2004-01-01

We provide an overview of the ecological and evolutionary interactions between oaks and several of their dispersal agents, and review a series of studies that demonstrate how various acorn characteristics affect feeding and caching decisions of these animals, which in turn may influence oak dispersal and establishment. We demonstrate that acorns of red oak species show...

Dietary sterol preference in the silkworm, Bombyx mori.

PubMed

Nagata, Shinji; Omori, Yukie; Nagasawa, Hiromichi

2006-12-01

Since insects are unable to biosynthesize sterols de novo, sterols must be obtained from dietary sources. Although it has been reported that beta-sitosterol is crucial for larval growth in the silkworm, Bombyx mori, little has been investigated concerning the dietary selection of sterols by Bombyx larvae. Here, we demonstrate that Bombyx larvae have the following sterol preference: beta-sitosterol > ergosterol > cholesterol = stigmasterol. Interestingly, Bombyx larvae preferred ergosterol, an inhibitory sterol on larval growth, indicating that sterol selection following first contact of the diet with the mouth part might be different from the sterol recognition mechanism present in sterol metabolism.

Systematic cloning and analysis of autophagy-related genes from the silkworm Bombyx mori

PubMed Central

Zhang, Xuan; Hu, Zhan-Ying; Li, Wei-Fang; Li, Qing-Rong; Deng, Xiao-Juan; Yang, Wan-Ying; Cao, Yang; Zhou, Cong-Zhao

2009-01-01

Background Through the whole life of eukaryotes, autophagy plays an important role in various biological events including development, differentiation and determination of lifespan. A full set of genes and their encoded proteins of this evolutionarily conserved pathway have been identified in many eukaryotic organisms from yeast to mammals. However, this pathway in the insect model organism, the silkworm Bombyx mori, remains poorly investigated. Results Based on the autophagy pathway in several model organisms and a series of bioinformatic analyses, we have found more than 20 autophagy-related genes from the current database of the silkworm Bombyx mori. These genes could be further classified into the signal transduction pathway and two ubiquitin-like pathways. Using the mRNA extracted from the silkgland, we cloned the full length cDNA fragments of some key genes via reverse transcription PCR and 3' rapid amplification of cDNA ends (RACE). In addition, we found that the transcription levels of two indicator genes BmATG8 and BmATG12 in the silkgland tend to be increased from 1st to 8th day of the fifth instar larvae. Conclusion Bioinformatics in combination with RT-PCR enable us to remodel a preliminary pathway of autophagy in the silkworm. Amplification and cloning of most autophagy-related genes from the silkgland indicated autophagy is indeed an activated process. Furthermore, the time-course transcriptional profiles of BmATG8 and BmATG12 revealed that both genes are up-regulated along the maturation of the silkgland during the fifth instar. These findings suggest that the autophagy should play an important role in Bombyx mori silkgland. PMID:19470186

Fitting Fire into Oak Management

Treesearch

Patrick Brose

2004-01-01

In the past decade, the use of prescribed fire in the mixed-oak forests of the eastern United States has markedly increased to help overcome the chronic lack of abundant, vigorous oak regeneration (Yaussy 2000). However, pre- scribed burns implemented under inappropriate circum- stances can result in failure to establish oak regeneration and/or loss of existing oak...

Foliar nutrients explain goldspotted oak borer, Agrilus auroguttatus, adult feeding preference among four California oak species

Treesearch

Yigen Chen; Tom. W. Coleman; Michael. I. Jones; Mary. L. Flint; Steven. J. Seybold

2013-01-01

Adults of the invasive goldspotted oak borer, Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), consumed foliar weight in no-choice feeding tests of, in descending order, California black oak Quercus kelloggii Newb., Engelmann oak, Quercus engelmannii Greene, coast live oak, Quercus...

Oak Tatters

Treesearch

Linda Haugen; Phil Marshall; Jane Cummings Carlson; Mark Vitosh; Ed Hayes

2000-01-01

Oak tatters is a relatively new condition that affects emerging oak leaves, causing them to appear lacy or tattered. It has been observed throughout the Midwestern United States, including Minnesota, Michigan, Wisconsin, Iowa, Illinois, Indiana, Ohio, and Missouri. This disorder was first reported during the 1980's in Iowa, Indiana and Ohio, but has been observed...

Sudden Oak Death - Western (Pest Alert)

Treesearch

Susan Frankel

2002-01-01

Tens of thousands of tanoak (Lithocarpus densiflorus), coast live oak (Quercus agrifolia), California black oak (Quercus kelloggii), Shreve oak (Quercus parvula var. shrevei), and madrone (Arbutus menziesii) have been killed by a newly identified species, Phytophthora ramorum, which causes Sudden Oak Death. Sudden Oak Death was first reported in 1995 in central coastal...

Sustaining northern red oak forests: managing oak from regeneration to canopy dominance in mature stands

Treesearch

Daniel C. Dey; Gary W. Miller; John M. Kabrick

2008-01-01

Across the range of northern red oak, managers have problems sustaining current stocking of northern red oak in forests. Oak species are adapted to frequent stand disturbances that reduce the abundance of shade tolerant competitors and control fast-growing pioneer species. A widely recommended approach to regenerating northern red oak is to develop relatively large...

Cherrybark Oaks From Perforated Containers Planted as Bareroots With Open-Grown Oak Bareroots

Treesearch

Kirk D. Howell

2002-01-01

Large Cherrybark oak (Q. pagoda Raf.) grown for two years (1997 and 1998) were hoedad planted in bottomlands near Columbia, South Carolina. Successful oak plantations exist from planted bareroot cherrybark oak seedlings with heights below 50 centimeters, but costly efforts were often employed to ensure success. To overcome competing vegetation,...

Oaks and Environmental Education

Treesearch

Kay Antunez de Mayolo

1991-01-01

A number of educational projects which focus on youth awareness and involvement with California oaks have been developed during the last five years. Primarily used in urban areas where oak populations have declined, many of these programs promote seedling propagation, tree planting and help to develop student understanding of environmental issues involving oaks while...

The paleohistory of California oaks

Treesearch

Scott Mensing

2015-01-01

Oak woodlands are a fixture of California geography, yet as recently as 10,000 years ago oaks were only a minor element in the landscape. The first fossil evidence for California's oaks is in the early Miocene (~20 million years ago) when oaks were present across the west, intermixed with deciduous trees typical of eastern North America. As climate became drier,...

Oak Tree Planting Project

Treesearch

Sherryl L. Nives; William D. Tietje; William H. Weitkamp

1991-01-01

An Oak Tree Planting Project was conducted during 1989/90 in San Luis Obispo County by the Integrated Hardwood Range Management Program (IHRMP)/Central Coast. The local media and an IHRMP workshop were used to publicize the Planting Project and give information on the status of oaks (Quercus spp.) in California and oak planting techniques. Outreach...

Comparative proteomics analysis of silkworm hemolymph during the stages of metamorphosis via liquid chromatography and mass spectrometry.

PubMed

Hou, Yong; Zhang, Yan; Gong, Jing; Tian, Sha; Li, Jianwei; Dong, Zhaoming; Guo, Chao; Peng, Li; Zhao, Ping; Xia, Qingyou

2016-05-01

The silkworm is a lepidopteran insect that has an open circulatory system with hemolymph consisting of blood and lymph fluid. Hemolymph is not only considered as a depository of nutrients and energy, but it also plays a key role in substance transportation, immunity response, and proteolysis. In this study, we used LC-MS/MS to analyze the hemolymph proteins of four developmental stages during metamorphosis. A total of 728 proteins were identified from the hemolymph of the second day of wandering stage, first day of pupation, ninth day of pupation, and first day as an adult moth. GO annotations and categories showed that silkworm hemolymph proteins were enriched in carbohydrate metabolism, proteolysis, protein binding, and antibacterial humoral response. The levels of nutrient, immunity-related, and structural proteins changed significantly during development and metamorphosis. Some, such as cuticle, odorant-binding, and chemosensory proteins, showed stage-specific expression in the hemolymph. In addition, the expression of several antimicrobial peptides exhibited their highest level of abundance in the hemolymph of the early pupal stage. These findings provide a comprehensive proteomic insight of the silkworm hemolymph and suggest additional molecular targets for studying insect metamorphosis. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The crucial role of cyclic GMP in the eclosion hormone mediated signal transduction in the silkworm metamorphoses.

PubMed

Shibanaka, Y; Hayashi, H; Okada, N; Fujita, N

1991-10-31

The signal transduction of the peptide, eclosion hormone, in the silkworm Bombyx mori appears to be mediated via the second messenger cyclic GMP throughout their life cycle. Injection of 8-bromo-cGMP induced the ecdysis behavior in pharate adults with similar latency to eclosion hormone-induced ecdysis; the moulting occurred 50-70 min after the injection. The potency of 8Br-cGMP was 10(2) fold higher than that of cGMP and the efficacy was increased by the co-injection of the phosphodiesterase inhibitor IBMX. On the other hand, in the silkworm pupal ecdysis the eclosion hormone and also 8Br-cGMP induced the moulting behavior in a dose-dependent manner. The adult development of the ability to respond to 8Br-cGMP took place concomitantly with the response to the eclosion hormone. Both the developmental time courses were shifted by a shift of light and dark cycles. Accordingly, the sensitivities to the peptide and cyclic nucleotide developed correspondently under the light and dark circadian rhythm. Thus throughout the silkworm life cycle, eclosion hormone is effective to trigger the ecdysis behavior and cGMP plays a crucial role as the second messenger in the eclosion hormone-mediated signal transduction.

The OakMapper WebGIS: improved access to sudden oak death spatial data

Treesearch

K. Tuxen; M. Kelly

2008-01-01

Access to timely and accurate sudden oak death (SOD) location data is critical for SOD monitoring, management and research. Several websites (hereafter called the OakMapper sites) associated with sudden oak death monitoring efforts have been maintained with up-todate SOD location information for over five years, providing information and maps of the most current...

Insect food for astronauts: gas exchange in silkworms fed on mulberry and lettuce and the nutritional value of these insects for human consumption during deep space flights.

PubMed

Tong, L; Yu, X; Liu, H

2011-10-01

In this study, silkworm moth (Bombyx mori L.) larvae were regarded as an animal protein source for astronauts in the bioregenerative life support system during long-term deep space exploration in the future. They were fed with mulberry and stem lettuce leaves during the first three instars and the last two instars, respectively. In addition, this kind of environmental approach, which utilised inedible biomass of plants to produce animal protein of high quality, can likewise be applied terrestrially to provide food for people living in extreme environments and/or impoverished agro-ecosystems, such as in polar regions, isolated military bases, ships, submarines, etc. Respiration characteristics of the larvae during development under two main physiological conditions, namely eating and not-eating of leaves, were studied. Nutrient compositions of silkworm powder (SP), ground and freeze-dried silkworms on the 3rd day of the 5th instar larvae, including protein, fat, vitamins, minerals and fatty acids, were measured using international standard methods. Silkworms' respiration rates, measured when larvae were eating mulberry leaves, were higher than those of similar larvae that hadn't eaten such leaves. There was a significant difference between silkworms fed on mulberry leaves and those fed on stem lettuce in the 4th and 5th instars (P<0.01). Amounts of CO2 exhaled by the silkworms under the two physiological regimes differed from each other (P<0.01). There was also a significant difference between the amount of O2 inhaled when the insects were under the two physiological statuses (P<0.01). Moreover, silkworms' respiration quotient under the eating regime was larger than when under the not-eating regime. The SP was found to be rich in protein and amino acids in total; 12 essential vitamins, nine minerals and twelve fatty acids were detected. Moreover, 359 kcal could be generated per 100 gram of SP (dry weight).

Hormonal regulation and developmental role of Krüppel homolog 1, a repressor of metamorphosis, in the silkworm Bombyx mori.

PubMed

Kayukawa, Takumi; Murata, Mika; Kobayashi, Isao; Muramatsu, Daisuke; Okada, Chieko; Uchino, Keiro; Sezutsu, Hideki; Kiuchi, Makoto; Tamura, Toshiki; Hiruma, Kiyoshi; Ishikawa, Yukio; Shinoda, Tetsuro

2014-04-01

Juvenile hormone (JH) has an ability to repress the precocious metamorphosis of insects during their larval development. Krüppel homolog 1 (Kr-h1) is an early JH-inducible gene that mediates this action of JH; however, the fine hormonal regulation of Kr-h1 and the molecular mechanism underlying its antimetamorphic effect are little understood. In this study, we attempted to elucidate the hormonal regulation and developmental role of Kr-h1. We found that the expression of Kr-h1 in the epidermis of penultimate-instar larvae of the silkworm Bombyx mori was induced by JH secreted by the corpora allata (CA), whereas the CA were not involved in the transient induction of Kr-h1 at the prepupal stage. Tissue culture experiments suggested that the transient peak of Kr-h1 at the prepupal stage is likely to be induced cooperatively by JH derived from gland(s) other than the CA and the prepupal surge of ecdysteroid, although involvement of unknown factor(s) could not be ruled out. To elucidate the developmental role of Kr-h1, we generated transgenic silkworms overexpressing Kr-h1. The transgenic silkworms grew normally until the spinning stage, but their development was arrested at the prepupal stage. The transgenic silkworms from which the CA were removed in the penultimate instar did not undergo precocious pupation or larval-larval molt but fell into prepupal arrest. This result demonstrated that Kr-h1 is indeed involved in the repression of metamorphosis but that Kr-h1 alone is incapable of implementing normal larval molt. Moreover, the expression profiles and hormonal responses of early ecdysone-inducible genes (E74, E75, and Broad) in transgenic silkworms suggested that Kr-h1 is not involved in the JH-dependent modulation of these genes, which is associated with the control of metamorphosis. Copyright © 2014 Elsevier Inc. All rights reserved.

GSOB ≠ SOD. Tree mortality from the goldspotted oak borer in oak woodlands of southern California.

Treesearch

Tom W. Coleman; Steven J. Seybold

2010-01-01

A new threat to oaks (Quercus spp.) in California was identified in June 2008 following years of misdiagnosis. The goldspotted oak borer (GSOB), Agrilus coxalis auroguttatus Schaeffer (Coleoptera: Buprestidae), is aggressively attacking and killing three species of oaks in oak woodlands in San Diego County. About 20,000...

AmeriFlux US-Oho Oak Openings

DOE Data Explorer

Chen, Jiquan [University of Toledo / Michigan State University

2016-01-01

This is the AmeriFlux version of the carbon flux data for the site US-Oho Oak Openings. Site Description - The Ohio Oak Openings site is located within the Oak Openings Preserve Metropark of northwest Ohio, one of the few remaining oak woodlands/savanna/prairie complexes in the Midwest. Declared one of the "One of America's Last Great Places" by the Nature Conservancy the area consists of four main vegetation types: Oak Woodlands, Oak Savanna, Floodplain Forests and Wet Prairies. The stand surrounding the tower is mainly Oak Woodlands dominated by red, white and black oaks with a relatively abundant population of red maples indicating high soil moisture retention and a history of limited fire disturbances. Most of the area was cleared for agriculture at the time of Euro-American settlements in the mid to late-19th century. A large fraction of the cleared land was later abandoned due to the poor sandy soils. These areas reverted to Oak Savannas and in cases where fire was limited progressively made the transition to Oak Woodlands. Today patches of the forest are burned every few years as part of prescribed burning cycle to control stand density.

Site Index Predictions for Red Oaks and White Oak in the Boston Mountains of Arkansas

Treesearch

D.L. Graney

1977-01-01

The relationship of soil and topography to site indices of northern red (Quercus rubra L. ), black (Q. uelutina Lam.) and white (Q. alba L.) oaks in the Boston Mountains indicates that white oaks should be favored for management on the finer-textured soils and on good south and west slope sites. Both red oaks and white oak could be managed on north- and east-facing...

When oak ordinances fail: unaddressed issues of oak conservation

Treesearch

Rudolph H. Light; Linda E. Pedroni

2002-01-01

The mandate by the California Board of Forestry in 1993 required each of the 41 counties which have significant oak woodlands to develop programs for the ultimate protection of this resource. As of 2001, a few counties have planned for the sustainability of their oak woodlands, but some counties may not be addressing the key components that will determine the overall...

Effects of midstory removal on underplanted black oak and white oak in the western Cumberland Plateau

Treesearch

David L. Parrott; John M. Lhotka; Jeffrey W. Stringer

2011-01-01

Difficulties in successful oak regeneration have led to the examination of various techniques to increase oak recruitment. To ensure sufficient regeneration, oak seedlings can be underplanted and used in conjunction with intermediate treatments, such as midstory removal, that create a light environment favorable to oak advance reproduction. This study examines the 5-...

Characterization of feeding-delaying factors from the silkworm Bombyx mori.

PubMed

Nagata, Shinji; Morooka, Nobukatsu; Matsumoto, Sumihiro; Nagasawa, Hiromichi

2009-04-01

In several phytophagous insects, feeding behavior occurs regularly. Recently, we demonstrated that feeding behavior in larvae of the silkworm Bombyx mori had a regular frequency. To address the control of the feeding cycle in B. mori, we aimed to characterize factors influencing feeding initiation and termination. Injection of extracts of the midgut, foregut, and fat body into starved Bombyx larvae delayed the initiation of feeding. This result indicates the presence in these tissues of factors capable of decreasing the likelihood of feeding initiation.

The effect of calorie restriction on growth and development in silkworm, Bombyx mori.

PubMed

Li, Yijia; Chen, Keping; Yao, Qin; Li, Jun; Wang, Yong; Liu, Haijun; Zhang, Chiyu; Huang, Guoping

2009-07-01

Caloric restriction (CR) is known to extend the life span in different species from yeast to mammals. In this report, a simple organism silkworm (Bombyx mori) was used to study the effect of moderate CR on the growth and development processes of insects. Here we show that an extension of life span upon moderate CR was observed in the silkworm. The total protein level in the 5th instar larvae hemolymph appeared to decline significantly under CR. SDS-PAGE analysis showed that the influence of CR was sex-dependent. The CR effects on female animals were much more significant than on the males. The MALDI-TOF MS study identified 16 proteins that expressed differentially among six groups of the male or female larvae fed at different time frequencies. Four of them, storage protein 1 (SP1), arylphorin (SP2), imaginal disk growth factor (IDGF), and 30-kDa lipoprotein, showed significant differences. It was demonstrated that these four proteins were up-regulated when the larvae were over-fed and down-regulated when the larvae were less-fed. (c) 2009 Wiley Periodicals, Inc.

Influence of clove oil and eugenol on muscle contraction of silkworm (Bombyx mori).

PubMed

Kheawfu, Kantaporn; Pikulkaew, Surachai; Hamamoto, Hiroshi; Sekimizu, Kazuhisa; Okonogi, Siriporn

2017-05-30

Clove oil is used in fish anesthesia and expected to have a mechanism via glutamic receptor. The present study explores the activities of clove oil and its major compound, eugenol, in comparison with L-glutamic acid on glutamic receptor of silkworm muscle and fish anesthesia. It was found that clove oil and eugenol had similar effects to L-glutamic acid on inhibition of silkworm muscle contraction after treated with D-glutamic acid and kainic acid. Anesthetic activity of the test samples was investigated in goldfish. The results demonstrated that L-glutamic acid at 20 and 40 mM could induce the fish to stage 3 of anesthesia that the fish exhibited total loss of equilibrium and muscle tone, whereas clove oil and eugenol at 60 ppm could induce the fish to stage 4 of anesthesia that the reflex activity of the fish was lost. These results suggest that clove oil and eugenol have similar functional activities and mechanism to L-glutamic acid on muscle contraction and fish anesthesia.

Can the silkworm (Bombyx mori) be used as a human disease model?

PubMed

Tabunoki, Hiroko; Bono, Hidemasa; Ito, Katsuhiko; Yokoyama, Takeshi

2016-02-01

Bombyx mori (silkworm) is the most famous lepidopteran in Japan. B. mori has long been used in the silk industry and also as a model insect for agricultural research. In recent years, B. mori has attracted interest in its potential for use in pathological analysis of model animals. For example, the human macular carotenoid transporter was discovered using information of B. mori carotenoid transporter derived from yellow-cocoon strain. The B. mori carotenoid transport system is useful in human studies. To develop a human disease model, we characterized the human homologs of B. mori, and by constructing KAIKO functional annotation pipeline, and to analyze gene expression profile of a unique B. mori mutant strain using microarray analysis. As a result, we identified a novel molecular network involved in Parkinson's disease. Here we describe the potential use of a spontaneous mutant silkworm strain as a human disease model. We also summarize recent progress in the application of genomic information for annotation of human homologs in B. mori. The B. mori mutant will provide a clue to pathological mechanisms, and the findings will be helpful for the development of therapies and for medical drug discovery.

Molecular characterization of a peritrophic membrane protein from the silkworm, Bombyx mori.

PubMed

Hu, Xiaolong; Chen, Lin; Yang, Rui; Xiang, Xingwei; Wu, Xiaofeng

2013-02-01

The peritrophic membrane lines the gut of most insects at one or more stages of their life cycles. It facilitates the digestive processes in the guts and protects from invasion by pathogens or food particles. In the current study, a novel PM protein, designated as BmMtch, was identified from the silkworm, Bombyx mori. The open reading frame of BmMtch is 888 bp in length, encoding 295 amino acid residues consisting of two domains (Mito_carr domains) and three transmembrane regions. They are localized on the 11th chromosome as single copy with one exon only. Quantitative real time PCR analysis (qRT-PCR) revealed that BmMtch was mainly expressed in larval fat bodies, Malpighian tubules, testis and ovaries, and could be detected through all stages of the life cycle of silkworm. Immuno-fluorescence analysis indicated that BmMtch was localized within the goblet cell of larval midgut. Western blotting analysis showed that BmMtch were detected in total proteins of PM and larval midgut. The characteristics of BmMtch indicated that BmMtch represents a novel member of insect PM proteins, without chitin-binding domains.

Oak regeneration why big is better

Treesearch

Paul P. Kormanik; Shi-Jean S. Sung; T.L. Kormanik; Stanley J. Zarnoch

1995-01-01

It is generally accepted that large preharvest advanced oak regeneration is required for maintaining a significant oak component in future stands. However, developing advanced oak regeneration on productive sites has been difficult because stand prescriptions encouraging oak regeneration are the same conditions that favor development of potentially faster growing...

Comparative analysis of the integument transcriptomes of the black dilute mutant and the wild-type silkworm Bombyx mori

PubMed Central

Wu, Songyuan; Tong, Xiaoling; Peng, Chenxing; Xiong, Gao; Lu, Kunpeng; hu, Hai; Tan, Duan; Li, Chunlin; Han, Minjin; Lu, Cheng; Dai, Fangyin

2016-01-01

The insect cuticle is a critical protective shell that is composed predominantly of chitin and various cuticular proteins and pigments. Indeed, insects often change their surface pigment patterns in response to selective pressures, such as threats from predators, sexual selection and environmental changes. However, the molecular mechanisms underlying the construction of the epidermis and its pigmentation patterns are not fully understood. Among Lepidoptera, the silkworm is a favorable model for color pattern research. The black dilute (bd) mutant of silkworm is the result of a spontaneous mutation; the larval body color is notably melanized. We performed integument transcriptome sequencing of the wild-type strain Dazao and the mutant strains +/bd and bd/bd. In these experiments, during an early stage of the fourth molt, a stage at which approximately 51% of genes were expressed genome wide (RPKM ≥1) in each strain. A total of 254 novel transcripts were characterized using Cuffcompare and BLAST analyses. Comparison of the transcriptome data revealed 28 differentially expressed genes (DEGs) that may contribute to bd larval melanism, including 15 cuticular protein genes that were remarkably highly expressed in the bd/bd mutant. We suggest that these significantly up-regulated cuticular proteins may promote melanism in silkworm larvae. PMID:27193628

Real-Time Mass Spectrometry Monitoring of Oak Wood Toasting: Elucidating Aroma Development Relevant to Oak-aged Wine Quality

NASA Astrophysics Data System (ADS)

Farrell, Ross R.; Wellinger, Marco; Gloess, Alexia N.; Nichols, David S.; Breadmore, Michael C.; Shellie, Robert A.; Yeretzian, Chahan

2015-11-01

We introduce a real-time method to monitor the evolution of oak aromas during the oak toasting process. French and American oak wood boards were toasted in an oven at three different temperatures, while the process-gas was continuously transferred to the inlet of a proton-transfer-reaction time-of-flight mass spectrometer for online monitoring. Oak wood aroma compounds important for their sensory contribution to oak-aged wine were tentatively identified based on soft ionization and molecular mass. The time-intensity profiles revealed toasting process dynamics illustrating in real-time how different compounds evolve from the oak wood during toasting. Sufficient sensitivity was achieved to observe spikes in volatile concentrations related to cracking phenomena on the oak wood surface. The polysaccharide-derived compounds exhibited similar profiles; whilst for lignin-derived compounds eugenol formation differed from that of vanillin and guaiacol at lower toasting temperatures. Significant generation of oak lactone from precursors was evident at 225 oC. Statistical processing of the real-time aroma data showed similarities and differences between individual oak boards and oak wood sourced from the different origins. This study enriches our understanding of the oak toasting process and demonstrates a new analytical approach for research on wood volatiles.

Silkworm cocoons inspire models for random fiber and particulate composites

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

Chen Fujia; Porter, David; Vollrath, Fritz

The bioengineering design principles evolved in silkworm cocoons make them ideal natural prototypes and models for structural composites. Cocoons depend for their stiffness and strength on the connectivity of bonding between their constituent materials of silk fibers and sericin binder. Strain-activated mechanisms for loss of bonding connectivity in cocoons can be translated directly into a surprisingly simple yet universal set of physically realistic as well as predictive quantitative structure-property relations for a wide range of technologically important fiber and particulate composite materials.

Silkworm cocoons inspire models for random fiber and particulate composites

NASA Astrophysics Data System (ADS)

Chen, Fujia; Porter, David; Vollrath, Fritz

2010-10-01

The bioengineering design principles evolved in silkworm cocoons make them ideal natural prototypes and models for structural composites. Cocoons depend for their stiffness and strength on the connectivity of bonding between their constituent materials of silk fibers and sericin binder. Strain-activated mechanisms for loss of bonding connectivity in cocoons can be translated directly into a surprisingly simple yet universal set of physically realistic as well as predictive quantitative structure-property relations for a wide range of technologically important fiber and particulate composite materials.

A practical guide to oak release.

Treesearch

Constance A. Harrington; Warren D. Devine

2006-01-01

Oregon white oak savannas and woodlands represent a biological and cultural legacy in the Pacific Northwest. Many Oregon white oak stands are deteriorating owing to invasion and eventual overtopping by Douglas-fir or other conifers. Releasing the shade-intolerant oak trees from overtopping conifers can often restore these oak stands. When planning a release operation,...

Scarlet Oak Sawfly (Pest Alert)

Treesearch

USDA Forest Service

1998-01-01

The scarlet oak sawfly, Caliroa quercuscoccineae (Dyar) skeletonizes leaves of scarlet, black, pin, and white oaks in eastern North America. It is also called the oak slug sawfly because of the fact that the larvae are covered with a coat of slime that helps them adhere to foliage.

Effects of Shade on Blue Oak and Coast Live Oak Regeneration in California Annual Grasslands

Treesearch

Pamela C. Muick

1991-01-01

Canopy effects and annual vegetation have been shown to strongly influence oak seedling survival. From the many elements composing canopy, shade was selected for experimental manipulation. A split-plot, multifactorial experiment was designed to test whether blue oak (Quercus douglasii) and coast live oak (Q. agrifolia) could...

Two Geminin homologs regulate DNA replication in silkworm, Bombyx mori.

PubMed

Tang, Xiao-Fang; Chen, Xiang-Yun; Zhang, Chun-Dong; Li, Yao-Feng; Liu, Tai-Hang; Zhou, Xiao-Lin; Wang, La; Zhang, Qian; Chen, Peng; Lu, Cheng; Pan, Min-Hui

2017-05-03

DNA replication is rigorously controlled in cells to ensure that the genome duplicates exactly once per cell cycle. Geminin is a small nucleoprotein, which prevents DNA rereplication by directly binding to and inhibiting the DNA replication licensing factor, Cdt1. In this study, we have identified 2 Geminin genes, BmGeminin1 and BmGeminn2, in silkworm, Bombyx mori. These genes contain the Geminin conserved coiled-coil domain and are periodically localized in the nucleus during the S-G2 phase but are degraded at anaphase in mitosis. Both BmGeminin1 and BmGeminin2 are able to homodimerize and interact with BmCdt1 in cells. In addition, BmGeminin1 and BmGeminin2 can interact with each other. Overexpression of BmGeminin1 affects cell cycle progression: cell cycle is arrested in S phase, and RNA interference of BmGeminin1 leads to rereplication. In contrast, overexpression or knockdown of BmGeminin2 with RNAi did not significantly affect cell cycle, while more rereplication occurred when BmGeminin1 and BmGeminin2 together were knocked down in cells than when only BmGeminin1 was knocked down. These data suggest that both BmGeminin1 and BmGeminin2 are involved in the regulation of DNA replication. These findings provide insight into the function of Geminin and contribute to our understanding of the regulation mechanism of cell cycle in silkworm.

Two Geminin homologs regulate DNA replication in silkworm, Bombyx mori

PubMed Central

Tang, Xiao-Fang; Chen, Xiang-Yun; Zhang, Chun-Dong; Li, Yao-Feng; Liu, Tai-Hang; Zhou, Xiao-Lin; Wang, La; Zhang, Qian; Chen, Peng; Lu, Cheng; Pan, Min-Hui

2017-01-01

ABSTRACT DNA replication is rigorously controlled in cells to ensure that the genome duplicates exactly once per cell cycle. Geminin is a small nucleoprotein, which prevents DNA rereplication by directly binding to and inhibiting the DNA replication licensing factor, Cdt1. In this study, we have identified 2 Geminin genes, BmGeminin1 and BmGeminn2, in silkworm, Bombyx mori. These genes contain the Geminin conserved coiled-coil domain and are periodically localized in the nucleus during the S-G2 phase but are degraded at anaphase in mitosis. Both BmGeminin1 and BmGeminin2 are able to homodimerize and interact with BmCdt1 in cells. In addition, BmGeminin1 and BmGeminin2 can interact with each other. Overexpression of BmGeminin1 affects cell cycle progression: cell cycle is arrested in S phase, and RNA interference of BmGeminin1 leads to rereplication. In contrast, overexpression or knockdown of BmGeminin2 with RNAi did not significantly affect cell cycle, while more rereplication occurred when BmGeminin1 and BmGeminin2 together were knocked down in cells than when only BmGeminin1 was knocked down. These data suggest that both BmGeminin1 and BmGeminin2 are involved in the regulation of DNA replication. These findings provide insight into the function of Geminin and contribute to our understanding of the regulation mechanism of cell cycle in silkworm. PMID:28379781

Upland Oak Regeneration and Management

Treesearch

David L. Loftis

2004-01-01

In oak-dominated plant communities and in other communities where oaks are important, the keys to natural regeneration of upland oak components are (1) to ensure presence of competitive regeneration sources, and (2) to provide timely, sufficient release of these sources. Regeneration sources vary significantly among different types of plant communities and disturbance...

INSECT SPECIES ON VEGETATION OF THE WHITE OAK LAKE BED, OAK RIDGE, TENNESSEE

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

Howden, H.F.; Crossley, D.A. Jr.

White Oak Lake, Oak Ridge, Tennessee, received lowlevel radioactive wastes from Oak Ridge National Laboratory for 12 years prior to draining in 1955. Studies on the insects inhabiting the vegetation on White Oak Lake bed revealed 401 species present during 1956 and 1957. Most numerous were members of the insect Orders Hymenoptera, Diptera, and Coleoptera. In the summer of 1956, the first summer following draining of the lake, there were relatively fewer species of insects represented by large numbers of individuals. In 1957, there were relatively more species of insects but fewer individuals were present. By the end of themore » summer of 1957, only two years after the lake was drained, the vegetation supported a rich and varied insect fauna. (C.H.)« less

Potential effects of sudden oak death on the oak woodland bird community of coastal California

Treesearch

William B. Monahan; Walter D. Koenig

2006-01-01

Oak-dependent birds are expected to suffer severe population declines as a result of sudden oak death (SOD). We investigated how the disappearance of two highly SOD-sensitive tree species, tanoak (Lithocarpus densiflorus) and coast live oak (Quercus agrifolia), may in turn affect levels of bird species richness, diversity, and...

Immune function of a Rab-related protein by modulating the JAK-STAT signaling pathway in the silkworm, Bombyx mori.

PubMed

Chen, Chen; Eldein, Salah; Zhou, Xiaosan; Sun, Yu; Gao, Jin; Sun, Yuxuan; Liu, Chaoliang; Wang, Lei

2018-01-01

The Rab-family GTPases mainly regulate intracellular vesicle transport, and play important roles in the innate immune response in invertebrates. However, the function and signal transduction of Rab proteins in immune reactions remain unclear in silkworms. In this study, we analyzed a Rab-related protein of silkworm Bombyx mori (BmRABRP) by raising antibodies against its bacterially expressed recombinant form. Tissue distribution analysis showed that BmRABRP mRNA and protein were high expressed in the Malpighian tubule and fat body, respectively. However, among the different stages, only the fourth instar larvae and pupae showed significant BmRABRP levels. After challenge with four pathogenic microorganisms (Escherichia coli, BmNPV, Beauveria bassiana, Micrococcus luteus), the expression of BmRABRP mRNA in the fat body was significantly upregulated. In contrast, the BmRABRP protein was significantly upregulated after infection with BmNPV, while it was downregulated by E. coli, B. bassiana, and M. luteus. A specific dsRNA was used to explore the immune function and relationship between BmRABRP and the JAK-STAT signaling pathway. After BmRABRP gene interference, significant reduction in the number of nodules and increased mortality suggested that BmRABRP plays an important role in silkworm's response to bacterial challenge. In addition, four key genes (BmHOP, BmSTAT, BmSOCS2, and BmSOCS6) of the JAK-STAT signaling pathway showed significantly altered expressions after BmRABRP silencing. BmHOP and BmSOCS6 expressions were significantly decreased, while BmSTAT and BmSOCS2 were significantly upregulated. Our results suggested that BmRABRP is involved in the innate immune response against pathogenic microorganisms through the JAK-STAT signaling pathway in silkworm. © 2017 Wiley Periodicals, Inc.

Vegetative characteristics of oak savannas in the southwestern United States: a comparative analysis with oak woodlands in the region

Treesearch

Peter F. Ffolliott; Gerald J. Gottfried

2005-01-01

Much has been learned about the oak woodlands of the Southwestern United States in recent years. However, comparable characterizations of the companion oak savannas are needed to help in enhancing the knowledge of all oak ecosystems in the Madrean Archipelago region. Oak savannas differ from oak woodlands in that they are more open in their structure with fewer trees...

Status of oak seedlings and saplings in the northern United States: implications for sustainability of oak forests

Treesearch

Chris W. Woodall; Randall S. Morin; Jim R. Steinman; Charles H. Perry

2008-01-01

Oak species are a substantial component of forest ecosystems in a 24-state region spanning the northern U.S. During recent decades, it has been documented that the health of oak forests has been experiencing large-scale decline. To further evaluate the sustainability of oak forests in nearly half the states of the U.S., the current status of oak seedlings and saplings...

MicroRNA profile of silk gland reveals different silk yields of three silkworm strains.

PubMed

Qin, Sheng; Danso, Blessing; Zhang, Jing; Li, Juan; Liu, Na; Sun, Xia; Hou, Chengxiang; Luo, Heng; Chen, Keping; Zhang, Guozheng; Li, Muwang

2018-05-05

Silk proteins are synthesized and secreted by the silk gland. The differential gene expression in it leads to different silk yield among various silkworm strains. As crucial factors, microRNAs (miRNAs) regulate protein synthesis at post-transcriptional level in silk gland. MiRNAs expression level in the silk gland of three silkworm strains (Jingsong, Lan10 and Dazao) was analyzed and 33 differentially expressed miRNAs (DEMs) were discovered between JingSong (JS) and Lan10 (L10), 60 DEMs between JS and Dazao, 54 DEMs between L10 and Dazao respectively. The DEMs target genes were predicted combing with two different methods and their functions were annotated according to gene ontology. Our previous studies showed that a batch of genes related to silk yield were identified in JS and L10 strains by comparative transcriptome and quantitative trait loci (QTL) method. Thirteen DEMs whose target genes are related to protein biosynthesis processes were screened by combining with these researches. Twelve DEMs potentially regulate nineteen genes which exist in our QTL results. Six common DEMs potentially regulate the genes in both of previous results. Finally, five DEMs were selected to verify their expression levels between JS and L10 by qRT-PCR, which showed similar difference as the results of small RNA-sequencing. MiRNAs in the silk gland may directly affect silk protein biosynthesis in different silkworm strains. In current work, we identified a batch of DEMs which potentially regulate the genes related to silk yield. Further functionally study of these miRNAs will contribute to improve varieties and boost the silk yield. Our research provides a basis for studying these miRNAs and their functions in silk production. Copyright © 2018 Elsevier B.V. All rights reserved.

The red oak - white oak forests of the Anthracite Region

Treesearch

C. F. Burnham; M. J. Ferree; F. E. Cunningham

1947-01-01

The red oak - white oak forests of the Anthracite Region occupy as substantial portion - 28.6 percent or 915,200 acres - of the region's 3,198,400 acres of forest land. These forests have been so heavily cut for lumber and mine timbers during the past 100 years and have been so badly ravaged by fire following these heavy cuttings that in their present condition...

Goldspotted oak borer

Treesearch

M.L. Flint; M. I. Jones; T. W. Coleman; S.J. Seybold

2013-01-01

The goldspotted oak borer (GSOB), Agrilus auroguttatus (Coleoptera: Buprestidae), is a flatheaded borer introduced to San Diego County, California, in the late 1990s or early 2000s and also detected at one site in Riverside County in 2012. It was likely brought into the state on oak firewood collected and transported from the insect's native...

Artificial “ping-pong” cascade of PIWI-interacting RNA in silkworm cells

PubMed Central

Shoji, Keisuke; Suzuki, Yutaka; Sugano, Sumio; Shimada, Toru; Katsuma, Susumu

2017-01-01

PIWI-interacting RNAs (piRNAs) play essential roles in the defense system against selfish elements in animal germline cells by cooperating with PIWI proteins. A subset of piRNAs is predicted to be generated via the “ping-pong” cascade, which is mainly controlled by two different PIWI proteins. Here we established a cell-based artificial piRNA production system using a silkworm ovarian cultured cell line that is believed to possess a complete piRNA pathway. In addition, we took advantage of a unique silkworm sex-determining one-to-one ping-pong piRNA pair, which enabled us to precisely monitor the behavior of individual artificial piRNAs. With this novel strategy, we successfully generated artificial piRNAs against endogenous protein-coding genes via the expected back-and-forth traveling mechanism. Furthermore, we detected “primary” piRNAs from the upstream region of the artificial “ping-pong” site in the endogenous gene. This artificial piRNA production system experimentally confirms the existence of the “ping-pong” cascade of piRNAs. Also, this system will enable us to identify the factors involved in both, or each, of the “ping” and “pong” cascades and the sequence features that are required for efficient piRNA production. PMID:27777367

Cathepsin O is involved in the innate immune response and metamorphosis of Antheraea pernyi.

PubMed

Sun, Yu-Xuan; Zhu, Bao-Jian; Tang, Lin; Sun, Yu; Chen, Chen; Nadeem Abbas, Muhammad; Wang, Lei; Qian, Cen; Wei, Guo-Qing; Liu, Chao-Liang

2017-11-01

Cathepsins are key members of mammalian papain-like cysteine proteases that play an important role in the immune response. In this study, a fragment of cDNA encoding cathepsin O proteinase (ApCathepsin O) was cloned from Antheraea pernyi. It contains an open reading frame of 1170bp and encodes a protein with 390 amino acid residues, including a conserved I29 inhibitor domain and a peptidase C1A (clan CA of cysteine proteases, papain family C1 subfamily) domain. Comparison with other previously reported cathepsin O proteins showed identity ranging from 45% to 79%. Quantitative real-time PCR (qRT-PCR) and Western blot analysis revealed that ApCathepsin O was highly expressed in the fat body; furthermore, the high expression during the pupal stage indicated that it might be involved during metamorphosis. After exposure to four different heat-killed pathogens (Escherichia coli, Beauveria bassiana, Micrococcus luteus, and A. pernyi nucleopolyhedrovirus), the expression levels of ApCathepsin O mRNA significantly increased and showed variable expression patterns. This indicates that ApCathepsin O is potentially involved in the innate immune system of A. pernyi. Interestingly, ApCathepsin O expression was upregulated after 20-hydroxyecdysone (20E) injection, which suggested that it might be regulated by 20E. In conclusion, ApCathepsin O is a protease that may play an important role in the innate immune response and metamorphosis of A. pernyi. Copyright © 2017. Published by Elsevier Inc.

Antheraea pernyi silk fibroin for targeted gene delivery of VEGF165-Ang-1 with PEI.

PubMed

Ma, Caili; Lv, Linlin; Liu, Yu; Yu, Yanni; You, Renchuan; Yang, Jicheng; Li, Mingzhong

2014-06-01

Vascularization is a crucial challenge in tissue engineering. One solution for this problem is to implant scaffolds that contain functional genes that promote vascularization by providing angiogenic growth factors via a gene delivery carrier. Poly(ethylenimine) (PEI) is a gene delivery carrier with high transfection efficiency but with cytotoxicity. To solve this problem, we utilized Antheraea pernyi silk fibroin (ASF), which has favorable cytocompatibility and biodegradability, RGD sequences and a negative charge, in conjunction with PEI, as the delivery vector for vascular endothelial growth factor (VEGF) 165-angiopoietin-1 (Ang-1) dual gene simultaneous expression plasmid, creating an ASF/PEI/pDNA complex. The results suggested that the zeta potential of the ASF/PEI/pDNA complex was significantly lower than that of the PEI/pDNA complex. Decreased nitrogen and increased oxygen on the surface of the complex demonstrated that the ASF had successfully combined with the surface of the PEI/pDNA. Furthermore, the complexes resisted digestion by nucleic acid enzymes and degradation by serum. L929 cells were cultured and transfected in vitro and improved cytotoxicity was found when the cells were transfected with ASF/PEI/pDNA compared with PEI/pDNA. In addition, the transfection efficiency and VEGF secretion increased. In general, this study provides a novel method for decreasing the cytotoxicity of PEI gene delivery vectors and increasing transfection efficiency of angiogenesis-related genes.

Silvicultural methods for regenerating oaks

Treesearch

F. Bryan Clark; Richard F. Watt

1971-01-01

Advance reproduction is the key to forming the new oak stand. However, the size or strength of the advance stems is just as important as number. Most oak stands approaching maturity have enough advance reproduction, but many do not. In such cases, harvest cuttings must be delayed and overstory densities regulated to favor the establishment and development of new oaks...

The historical significance of oak

Treesearch

J. V. Thirgood

1971-01-01

A brief history of the importance of oak in Europe, contrasting the methods used in France and Britain to propagate the species and manage the forests for continued productivity. The significance of oak as a strategic resource during the sailing-ship era is stressed, and mention is made of the early development of oak management in North America. The international...

Silkworm dropping extract ameliorate trimellitic anhydride-induced allergic contact dermatitis by regulating Th1/Th2 immune response.

PubMed

Choi, Dae Woon; Kwon, Da-Ae; Jung, Sung Keun; See, Hye-Jeong; Jung, Sun Young; Shon, Dong-Hwa; Shin, Hee Soon

2018-05-26

Allergic contact dermatitis (ACD) is an inflammatory skin disease caused by hapten-specific immune response. Silkworm droppings are known to exert beneficial effects during the treatment of inflammatory diseases. Here, we studied whether topical treatment and oral administration of silkworm dropping extract (SDE) ameliorate trimellitic anhydride (TMA)-induced ACD. In ACD mice model, SDE treatment significantly suppressed the increase in both ear thickness and serum IgE levels. Furthermore, IL-1β and TNF-α levels were reduced by SDE. In allergic responses, SDE treatment significantly attenuated the production of the Th2-associated cytokine IL-4 in both ear tissue and draining lymph nodes. However, it increased the production of the Th1-mediated cytokine IL-12. Thus, these results showed that SDE attenuated TMA-induced ACD symptoms through regulation of Th1/Th2 immune response. Taken together, we suggest that SDE treatment might be a potential agent in the prevention or therapy of Th2-mediated inflammatory skin diseases such as ACD and atopic dermatitis. ACD: allergic contact dermatitis; AD: atopic dermatitis; APC: antigen presenting cells; CCL: chemokine (C-C motif) ligand; CCR: C-C chemokine receptor; Dex: dexamethasone; ELISA: enzyme-linked immunosorbent assay; IFN: interferon; Ig: immunoglobulin; IL: interleukin; OVA: ovalbumin; PS: prednisolone; SDE: silkworm dropping extract; Th: T helper; TMA: trimellitic anhydride; TNF: tumor necrosis factor.

Propagation of Southern Red Oak and Water Oak by Rooted Cuttings

Treesearch

Horace J. Duncan; Fred R. Matthews

1969-01-01

Southern red oak and water oak, needed in studies of fusiform rust of southern pines, were propagated from cuttings of rooted stump sprouts and mature tree branches placed in outdoor propagation beds in June. Root strike and root development were increased when cuttings with basal wounds were treated with both the hormone IBA and the fungicide folpet. Cuttings from...

Quantitative proteomic and transcriptomic analyses of molecular mechanisms associated with low silk production in silkworm Bombyx mori.

PubMed

Wang, Shao-Hua; You, Zheng-Ying; Ye, Lu-Peng; Che, Jiaqian; Qian, Qiujie; Nanjo, Yohei; Komatsu, Setsuko; Zhong, Bo-Xiong

2014-02-07

To investigate the molecular mechanisms underlying the low fibroin production of the ZB silkworm strain, we used both SDS-PAGE-based and gel-free-based proteomic techniques and transcriptomic sequencing technique. Combining the data from two different proteomic techniques was preferable in the characterization of the differences between the ZB silkworm strain and the original Lan10 silkworm strain. The correlation analysis showed that the individual protein and transcript were not corresponded well, however, the differentially changed proteins and transcripts showed similar regulated direction in function at the pathway level. In the ZB strain, numerous ribosomal proteins and transcripts were down-regulated, along with the transcripts of translational related elongation factors and genes of important components of fibroin. The proteasome pathway was significantly enhanced in the ZB strain, indicating that protein degradation began on the third day of fifth instar when fibroin would have been produced in the Lan10 strain normally and plentifully. From proteome and transcriptome levels of the ZB strain, the energy-metabolism-related pathways, oxidative phosphorylation, glycolysis/gluconeogenesis, and citrate cycle were enhanced, suggesting that the energy metabolism was vigorous in the ZB strain, while the silk production was low. This may due to the inefficient energy employment in fibroin synthesis in the ZB strain. These results suggest that the reason for the decreasing of the silk production might be related to the decreased ability of fibroin synthesis, the degradation of proteins, and the inefficiency of the energy exploiting.

Shotgun proteomics approach to characterizing the embryonic proteome of the silkworm, Bombyx mori, at labrum appearance stage.

PubMed

Li, J-Y; Chen, X; Hosseini Moghaddam, S H; Chen, M; Wei, H; Zhong, B-X

2009-10-01

The shotgun approach has gained considerable acknowledgement in recent years as a dominant strategy in proteomics. We observed a dramatic increase of specific protein spots in two-dimensional electrophoresis (2-DE) gels of the silkworm (Bombyx mori) embryo at labrum appearance, a characteristic stage during embryonic development of silkworm which is involved with temperature increase by silkworm raiser. We employed shotgun liquid chromatography tandem mass spectrometry (LC-MS/MS) technology to analyse the proteome of B. mori embryos at this stage. A total of 2168 proteins were identified with an in-house database. Approximately 47% of them had isoelectric point (pI) values distributed theoretically in the range pI 5-7 and approximately 60% of them had molecular weights of 15-45 kDa. Furthermore, 111 proteins had an pI greater than 10 and were difficult to separate by 2-DE. Many important functional proteins related to embryonic development, stress response, DNA transcription/translation, cell growth, proliferation and differentiation, organogenesis and reproduction were identified. Among them proteins related to nervous system development were noticeable. All known heat shock proteins (HSPs) were detected in this developmental stage of B. mori embryo. In addition, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed energetic metabolism at this stage. These results were expected to provide more information for proteomic monitoring of the insect embryo and better understanding of the spatiotemporal expression of genes during embryonic developmental processes.

The Wye Oaks on Campus | Poster

Cancer.gov

The Wye Oak tree—a towering white oak that lived for nearly 500 years in Talbot County, Maryland—was the nation’s largest white oak tree as well as the State Tree of Maryland until it was destroyed in a severe thunderstorm in 2002. Today, several clones of the Wye Oak, as well as a few of the Wye Oak’s progeny, still exist—including two on the NCI at Frederick campus.

Purple martins in oak woodlands

Treesearch

Brian D. C. Williams

2002-01-01

Purple martins are cavity-nesting swallows that once nested fairly widely in California’s oak woodlands but are now rare in that habitat. The old oaks of the Tehachapi Range (southern Sierra Nevada) may now host the last martins that nest in oak woodlands, with approximately 100-200 pairs or about 15 percent of the California population. In summer of 2000, we found 57...

Insect-oak interactions with coast live oak (Quercus agrifolia) and Engelmann oak (Q. engelmannii) at the acorn and seedling stage

Treesearch

Connell E. Dunning; Timothy D. Paine; Richard A. Redak

2002-01-01

We determined the impact of insects on both acorns and seedlings of coast live oak (Quercus agrifolia Nee) and Engelmann oak (Quercus engelmannii E. Greene). Our goals were to (1) identify insects feeding on acorns and levels of insect damage, and (2) measure performance and preference of a generalist leaf-feeding insect herbivore...

How to Distinguish Oak LEAFTIERS From LEAFROLLERS

Treesearch

Parker Snowden

1990-01-01

Oak leaftiers and oak leafrollers defoliate oaks throughout the northeastern United States and adjoining Canadian provinces. In recent years, scattered but severe outbreaks of oak leaftier have occurred in Connecticut, Massachusetts, New Jersey, New York, Pennsylvania, and West Virginia. In 1978 more than 100,000 acres were defoliated in these states....

Oak mortality risk factors and mortality estimation

Treesearch

Stephen R. Shifley; Zhaofei Fan; John M. Kabrick; Randy G. Jensen

2006-01-01

Managers are often concerned about oak mortality in maturing mixed-oak forests, but they often lack explicit information about mortality risk for oaks that differ in species, size, crown class, competitive status, and growth rate. In eastern North America, tree species in the red oak group (Quercus Section Lobatae) are typically...

Structure and physical properties of silkworm cocoons

PubMed Central

Chen, Fujia; Porter, David; Vollrath, Fritz

2012-01-01

Silkworm cocoons have evolved a wide range of different structures and combinations of physical and chemical properties in order to cope with different threats and environmental conditions. We present our observations and measurements on 25 diverse types of cocoons in a first attempt to correlate physical properties with the structure and morphology of the cocoons. These two architectural parameters appear to be far more important than the material properties of the silk fibres themselves. We consider tensile and compressive mechanical properties and gas permeation of the cocoon walls, and in each case identify mechanisms or models that relate these properties to cocoon structure, usually based upon non-woven fibre composites. These properties are of relevance also for synthetic non-woven composite materials and our studies will help formulate bio-inspired design principles for new materials. PMID:22552916

Spermidine enhances the silk production by mulberry silkworm.

PubMed

Lattala, Gayatri Manogna; Kandukuru, Kasturaiah; Gangupantula, Shamitha; Mamillapalli, Anitha

2014-01-01

Polyamines are ubiquitous low molecular weight polycationic aliphatic amines involved in diverse cellular processes. Spermidine (Spd), a polyamine, has been proved to be crucial for cell survival in various organisms. Our study reports the effect of Spd on the growth of Bombyx mori. Silkworms showed improved silk gland weight and economic parameters in the fifth instar larval stage when treated with different concentrations of Spd, in the range of 25-75 µM. The worms treated with Spd produced 31% more silk when compared with the control worms. Altogether, this study establishes that Spd-treated leaves can be fed into the larvae for better silk production. © The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.

The Physiology and Biochemistry of Desiccating White Oak and Cherrybark Oak Acorns

Treesearch

Kristina F. Connor; Sharon Sowa

2004-01-01

The recalcitrant behavior of white oak (Quercus alba L.) and cherrybark oak (Q. pagoda Raf.) acorns was examined in terms of effects of moisture content on seed longevity, viability, and biochemistry. Acorns of both species were fully hydrated and then subjected to drying under ambient conditions of temperature and relative...

Stress induction of Bm1 RNA in silkworm larvae: SINEs, an unusual class of stress genes

PubMed Central

Kimura, Richard H.; Choudary, Prabhakara V.; Stone, Koni K.; Schmid, Carl W.

2001-01-01

This study surveys the induction of RNA polymerase III (Pol III)–directed expression of short interspersed element (SINE) transcripts by various stresses in an animal model, silkworm larvae. Sublethal heat shock and exposure to several toxic compounds increase the level of Bm1 RNA, the silkworm SINE transcript, while also transiently increasing expression of a well-characterized stress-induced transcript, Hsp70 messenger RNA (mRNA). In certain cases, the Bm1 RNA response coincides with that of Hsp70 mRNA, but more often Bm1 RNA responds later in recovery. Baculovirus infection and exposure to certain toxic compounds increase Bm1 RNA but not Hsp70 mRNA, showing that SINE induction is not necessarily coupled to transcription of this particular heat shock gene. SINEs behave as an additional class of stress-inducible genes in living animals but are unusual as stress genes because of their high copy number, genomic dispersion, and Pol III–directed transcription. PMID:11599568

A novel immune-related gene HDD1 of silkworm Bombyx mori is involved in bacterial response.

PubMed

Zhang, Kui; Pan, Guangzhao; Zhao, Yuzu; Hao, Xiangwei; Li, Chongyang; Shen, Li; Zhang, Rui; Su, Jingjing; Cui, Hongjuan

2017-08-01

Insects have evolved an effective immune system to respond to various challenges. In this study, a novel immune-related gene, called BmHDD1, was first charactered in silkworm, Bombyx mori. BmHDD1 contained an ORF of 837bp and encoding a deduced protein of 278 amino acids. BmHDD1 was specifically expressed in hemocytes, and highly expressed at the molting and metamorphosis stages under normal physiological conditions. Our results suggested that BmHDD1 was mainly generated by hemocytes and secreted into hemolymph. Our results also showed that the expression level of BmHDD1 was significantly increased after 20E injection, which indicated that BmHDD1 might be regulated by ecdysone. More importantly, BmHDD1 was dramatically induced after injected with different types of PAMPs or bacteria, either in hemocytes or fat body. Those results suggested that BmHDD1 plays a role in developing and immunity system in silkworm, Bombyx mori. Copyright © 2017. Published by Elsevier Ltd.

Change in soil quality due to grazing and oak tree removal in California blue oak woodlands

Treesearch

Trina J. Camping; Randy A. Dahlgren; Kenneth W. Tate; William R. Horwath

2002-01-01

The effects of grazing and oak tree removal on soil quality and fertility were examined in a blue oak (Quercus douglasii) woodland in the northern Sierra Nevada foothills. Low to moderate grazing intensity has little affect on soil quality; however, oak tree removal resulted in a decrease in most soil quality parameters investigated (carbon, nitrogen...

HOW to Distinguish Oak LEAFTIERS From LEAFROLLERS

Treesearch

Parker Snowden

1990-01-01

Oak leaftiers and oak leafrollers defoliate oaks throughout the northeastern United States and adjoining Canadian provinces. In recent years, scattered but severe outbreaks of oak Leaftier have occurred in Connecticut, Massachusetts, New Jersey, New York, Pennsylvania, and West Virginia. In 1978 more than 100,000 acres were defoliated in these states. Outbreaks of the...

A Crown Cover Chart for Oak Savannas

Treesearch

Jay Law; Paul Johnson; Gary Houf

1994-01-01

Although oak savannas have been defined in many ways, they are characterized by scattered trees, largely comprised of oaks, and a sparse ground layer rich in grasses and forbs (Haney and Apfelbaum 1990). Nuzzo (1986, p. 11) more specifically defined oak savannas as plant communities "...dominated by oaks having between 10 and 80 percent canopy, with or without a...

Quercus kelloggii Newb., California black oak

Treesearch

P.M. McDonald

1990-01-01

California black oak (Quercus kelloggii) exceeds all other California oaks in volume, distribution, and altitudinal range. Yet this deciduous hardwood has had little sustained commercial use and almost no management, even though its wood closely resembles that of its valuable, managed, and heavily used counterpart-northern red oak (...

Five southern California oaks: identification and postfire management

Treesearch

Timothy R. Plumb; Anthony P. Gomez

1983-01-01

Oak trees in California are subject to periodic burning by fire, but their trunks and crowns vary in tolerance to fire. And once burned, oaks are difficult to identify by species. Fifteen oak species grow in California. This report provides keys to identifying five species of southern California oaks: coast live oak (Quercus agrifolia Née...

Effect of phosphate treatments on sudden oak death in tanoak and Shreve's oak

Treesearch

Doug Schmidt; Matteo Garbelotto; Dave Chambers; Steve Tjosvold

2006-01-01

Field experiments were conducted to evaluate the effectiveness of phosphonate chemical treatments for control of sudden oak death in tanoak (Lithocarpus densiflorus) and Shreve's oak (Quercus parvula var. Shrevei). Native stands of mature trees were preventatively treated with Agrifos® systemic fungicide and...

Effect of acorn moisture content at sowing on germination and seedling growth of white oak and northern red oak

Treesearch

Shi-Jean Susana Sung; Paul P. Kormanik; Catharine D. Cook; Stanley J. Zarnoch; Taryn L. Kormanik

2006-01-01

White oak (Quercus alba L.) and northern red oak (Q. rubra L.) acorns were collected locally or from seed orchards in October 2002. Mean acorn moisture content (MC) was 48 percent for white oak and 39 percent for northern red oak. These acorns were air dried to different MCs before being sown into nursery beds in early December...

Restoring Native California Oaks on Grazed Rangelands

Treesearch

Douglas D. McCreary; Jerry Tecklin

2005-01-01

Efforts to regenerate oaks on California’s oak woodlands often must address how to establish seedlings in areas grazed by livestock. Research indicates that damage to young oak seedlings from cattle varies by season, with less damage during the winter when deciduous oaks do not have leaves. While exclusion of cattle from planted areas does result in reduced damage, the...

Developing a stand hazard index for oak decline in upland Oak forests of the Ozark Highlands, Missouri

Treesearch

Fan Zhaofei; Fan Xiuli; Martin A. Spetich; Stephen R. Shifley; W. Keith Moser; Randy G. Jensen; John M. Kabrick

2011-01-01

Black oak (Quercus velutina Lam.) and scarlet oak (Quercus coccinea Muenchh.)--two major components (44% of total stand basal area) of upland oak forests--are suffering severe decline and mortality in the Ozark Highlands, Missouri. However, factors influencing their survival (mortality) are not well understood. In this study we...

De novo transcriptome assembly and analysis of differential gene expression following peptidoglycan (PGN) challenge in Antheraea pernyi.

PubMed

Liu, Yu; Xin, Zhao-Zhe; Zhang, Dai-Zhen; Zhu, Xiao-Yu; Wang, Ying; Chen, Li; Tang, Bo-Ping; Zhou, Chun-Lin; Chai, Xin-Yue; Tian, Ji-Wu; Liu, Qiu-Ning

2018-06-01

Antheraea pernyi is not only an important economic insect, it is increasingly employed as a model organism due to a variety of advantages, including ease of rearing and experimental manipulation compared with other Lepidoptera. Peptidoglycan (PGN) is a major component of the bacterial cell wall, and interactions between PGN and A. pernyi cause a series of physiological changes in the insect. In the present study, we constructed cDNA libraries from a A. pernyi PGN-infected group and a control group stimulated with phosphate-buffered saline (PBS). The transcriptome was de novo assembled using the Trinity platform, and 1698 differentially expressed genes (DEGs) were identified, comprising 894 up-regulated and 804 down-regulated genes. To further investigate immune-related DEGs, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment were performed. GO analysis identified major immune-related GO terms and KEGG enrichment indicated gene responses to three pathways related to the insect immune system. Several homologous genes related to the immune response of the A. pernyi fat body post-PGN infection were identified and categorised. Taken together, the results provide insight into the complex molecular mechanisms of the responses to bacterial infection at the transcriptional level. Copyright © 2018 Elsevier B.V. All rights reserved.

Oak savanna restoration: Oak response to fire and thinning through 28 years

Treesearch

Ronald E. Masters; Jack R. Waymire

2012-01-01

We used a small plot study on Pushmataha Wildlife Management Area in southeast Oklahoma to determine the efficacy of fire frequency and thinning as management tools for restoration of oak savanna, oak woodlands, pine-bluestem woodlands, and pine savanna for application on a landscape scale. On selected experimental units, we initially reduced stand density to favor...

Bombyx mori P-element Somatic Inhibitor (BmPSI) Is a Key Auxiliary Factor for Silkworm Male Sex Determination

PubMed Central

Chen, Shuqing; Zeng, Baosheng; James, Anthony A.; Tan, Anjiang; Huang, Yongping

2017-01-01

Manipulation of sex determination pathways in insects provides the basis for a wide spectrum of strategies to benefit agriculture and public health. Furthermore, insects display a remarkable diversity in the genetic pathways that lead to sex differentiation. The silkworm, Bombyx mori, has been cultivated by humans as a beneficial insect for over two millennia, and more recently as a model system for studying lepidopteran genetics and development. Previous studies have identified the B. mori Fem piRNA as the primary female determining factor and BmMasc as its downstream target, while the genetic scenario for male sex determination was still unclear. In the current study, we exploite the transgenic CRISPR/Cas9 system to generate a comprehensive set of knockout mutations in genes BmSxl, Bmtra2, BmImp, BmImpM, BmPSI and BmMasc, to investigate their roles in silkworm sex determination. Absence of Bmtra2 results in the complete depletion of Bmdsx transcripts, which is the conserved downstream factor in the sex determination pathway, and induces embryonic lethality. Loss of BmImp or BmImpM function does not affect the sexual differentiation. Mutations in BmPSI and BmMasc genes affect the splicing of Bmdsx and the female reproductive apparatus appeared in the male external genital. Intriguingly, we identify that BmPSI regulates expression of BmMasc, BmImpM and Bmdsx, supporting the conclusion that it acts as a key auxiliary factor in silkworm male sex determination. PMID:28103247

Fire effects in northeastern forests: oak.

Treesearch

Cary Rouse

1986-01-01

Effects of fire on the oak timber type are reviewed. Many oak stands of today originated under severe fire regimes. Fire can ill or injure oak trees. Factors determining direct injury or mortality from fire include: season of year; bark characteristics; size, vigor and form of tree; fire characteristics and stocking level.

Conifer encroachment in California oak woodlands

Treesearch

Matthew I. Cocking; J. Morgan Varner; Eamon A. Engber

2015-01-01

California deciduous oak woodlands provide many ecological, cultural, and economic benefits, and often represent unique plant communities that harbor native rare and declining species. Oak woodlands have suffered substantial losses in area and ecological integrity in the post-settlement era due to land conversion and widespread fire exclusion. Remnant oak woodlands in...

An oak wilt primer

Treesearch

Jennifer Juzwik

2000-01-01

Oak wilt, caused by the fungus Ceratocystis fagacearum {Bretz} Hunt, is an important disease of oaks (Quercus spp.) in the eastern United States. the disease occurs in 22 states and is considered the most important forest disease problem in Illinois, Iowa, Minnesota, Texas and Wisconsin. The pathogen causes mortality of thousands...

Variations in juvenile oak

Treesearch

Peter W. Garrett; Harry C. Kettlewood

1975-01-01

Data from research on 13-year-old trees in an oak planting in southeastern Pennsylvania indicate that survival and growth are not correlated with source latitude within all species tested. A complete listing of species and seed origins, along with performance of progenies, is presented for persons interested in oak improvement.

Reconstituted products from oak

Treesearch

W. C. Lewis; B. G. Heebink

1971-01-01

"Reconstituted" describes a family of panel products made from fractionated oak, bonded with either a synthetic resin or a natural lignin bond. Several current commercial fiber panel products from oak are described, and the status of research on experimental products and processes is presented. Recent technological developments are removing the stigma...

California oaks: a bibliography

Treesearch

James R. Griffin; Philip M. McDonald; Pamela C. Muick

1987-01-01

Among natural resource professionals, California oaks continue to attract considerable attention. This report provides a comprehensive bibliography of the extensive but scattered oak literature. The 768 references are organized into two systems: (a) a topical outline, in which references are displayed under key word headings and subheadings, and author-date entries...

Functional Loss of Bmsei Causes Thermosensitive Epilepsy in Contractile Mutant Silkworm, Bombyx mori

PubMed Central

Nie, Hongyi; Cheng, Tingcai; Huang, Xiaofeng; Zhou, Mengting; Zhang, Yinxia; Dai, Fangyin; Mita, Kazuei; Xia, Qingyou; Liu, Chun

2015-01-01

The thermoprotective mechanisms of insects remain largely unknown. We reported the Bombyx mori contractile (cot) behavioral mutant with thermo-sensitive seizures phenotype. At elevated temperatures, the cot mutant exhibit seizures associated with strong contractions, rolling, vomiting, and a temporary lack of movement. We narrowed a region containing cot to ~268 kb by positional cloning and identified the mutant gene as Bmsei which encoded a potassium channel protein. Bmsei was present in both the cell membrane and cytoplasm in wild-type ganglia but faint in cot. Furthermore, Bmsei was markedly decreased upon high temperature treatment in cot mutant. With the RNAi method and injecting potassium channel blockers, the wild type silkworm was induced the cot phenotype. These results demonstrated that Bmsei was responsible for the cot mutant phenotype and played an important role in thermoprotection in silkworm. Meanwhile, comparative proteomic approach was used to investigate the proteomic differences. The results showed that the protein of Hsp-1 and Tn1 were significantly decreased and increased on protein level in cot mutant after thermo-stimulus, respectively. Our data provide insights into the mechanism of thermoprotection in insect. As cot phenotype closely resembles human epilepsy, cot might be a potential model for the mechanism of epilepsy in future. PMID:26198671

Functional Loss of Bmsei Causes Thermosensitive Epilepsy in Contractile Mutant Silkworm, Bombyx mori

NASA Astrophysics Data System (ADS)

Nie, Hongyi; Cheng, Tingcai; Huang, Xiaofeng; Zhou, Mengting; Zhang, Yinxia; Dai, Fangyin; Mita, Kazuei; Xia, Qingyou; Liu, Chun

2015-07-01

The thermoprotective mechanisms of insects remain largely unknown. We reported the Bombyx mori contractile (cot) behavioral mutant with thermo-sensitive seizures phenotype. At elevated temperatures, the cot mutant exhibit seizures associated with strong contractions, rolling, vomiting, and a temporary lack of movement. We narrowed a region containing cot to ~268 kb by positional cloning and identified the mutant gene as Bmsei which encoded a potassium channel protein. Bmsei was present in both the cell membrane and cytoplasm in wild-type ganglia but faint in cot. Furthermore, Bmsei was markedly decreased upon high temperature treatment in cot mutant. With the RNAi method and injecting potassium channel blockers, the wild type silkworm was induced the cot phenotype. These results demonstrated that Bmsei was responsible for the cot mutant phenotype and played an important role in thermoprotection in silkworm. Meanwhile, comparative proteomic approach was used to investigate the proteomic differences. The results showed that the protein of Hsp-1 and Tn1 were significantly decreased and increased on protein level in cot mutant after thermo-stimulus, respectively. Our data provide insights into the mechanism of thermoprotection in insect. As cot phenotype closely resembles human epilepsy, cot might be a potential model for the mechanism of epilepsy in future.

Reducing borer damage in oak regeneration and sawtimber

Treesearch

Jimmy R. Galford

1989-01-01

Borers cause millions of dollars in damaged wood annually to oak stands, and adversely affect the form and vigor of oak regeneration. A moth and four species of beetles cause most of the damage; the carpenterworm moth, the oak timberworm, the red oak borer, the living-beech borer, and the white oak borer. The larvae of these insects chew holes in the wood ranging from...

Fabrication and Characterization of Conductive Conjugated Polymer-Coated Antheraea mylitta Silk Fibroin Fibers for Biomedical Applications.

PubMed

Gh, Darshan; Kong, Dexu; Gautrot, Julien; Vootla, Shyam Kumar

2017-07-01

Conductive polymers are interesting materials for a number of biological and medical applications requiring electrical stimulation of cells or tissues. Highly conductive polymers (polypyrrole and polyaniline)/Antheraea mylitta silk fibroin coated fibers are fabricated successfully by in situ polymerization without any modification of the native silk fibroin. Coated fibers characterized by scanning electron microscopy confirm the silk fiber surface is covered by conductive polymers. Thermogravimetric analysis reveals preserved thermal stability of silk fiber after coating process. X-ray diffraction of degummed fiber diffraction peaks at around 2θ = 20.4 and 16.5 confirms the preservation of the β-sheet structure typical of degummed silk II fibers. This phenomenon implies that both polypyrrole and polyaniline chains form interactions with peptide linkages in degummed fiber macromolecules, without significantly disrupting protein assembly. Fourier transform infrared spectroscopy of coated fibers indicates hydrogen bonding and electrostatic interactions exist between silk fibroin macromolecules and conductive polymers. Resulting fibers display good conductive properties compared to corresponding conjugated polymers. In vitro analysis (live/dead assay) of the behavior of human immortalized keratinocytes (HaCaTs) on coated fibers demonstrates improved cell-adhesive properties and viability after polymers coating. Hence, polypyrrole- and polyaniline-coated A. mylitta silk fibers are suitable for application in cell culture and for tissue engineering, where electrical conduction properties are required. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Silkworm larvae plasma (SLP) assay for detection of bacteria: False positives secondary to inflammation in vivo.

PubMed

Ma, Michelle; Rice, Tyler A; Percopo, Caroline M; Rosenberg, Helene F

2017-01-01

The silkworm larvae plasma (SLP) assay has been developed as a means to detect bacterial peptidoglycan as a surrogate for live bacteria. Here, we present results that indicate that generation of melanin by this assay is not fully reliable as a surrogate marker for bacterial count. Published by Elsevier B.V.

How to identify and manage oak wilt in Texas

Treesearch

D.N. Appel; R.S. Cameron; A.D. Wilson; J.D. Johnson

2008-01-01

Transporting unseasoned firewood from diseased red oaks is a potential means of spreading the oak wilt fungus. Oak wilt cannot be transmitted by burning infected firewood, but fungal mats may form on firewood in storage. Presently, no vectors have been proven to transmit the fungus from live oaks to other oak trees, but diseased wood fromany oak species should never be...

Sudden Oak Death - Eastern (Pest Alert)

Treesearch

Joseph O' Brien; Manfred Mielke; Steve Oak; Bruce Moltzan

2002-01-01

A phenomenon known as Sudden Oak Death was first reported in 1995 in central coastal California. Since then, tens of thousands of tanoaks (Lithocarpus densiflorus), coast live oaks (Quercus agrifolia), and California black oaks (Quercus kelloggii) have been killed by a newly identified fungus, Phytophthora ramorum. On these hosts, the fungus causes a bleeding canker on...

Regenerating oaks with the shelterwood system

Treesearch

Ivan L. Sander

1979-01-01

It is well known that a new reproduction stand that follows complete overstory removal will contain oaks in proportion to the numbers and size of advance oak reproduction present before the overstory was removed. Furthermore, the individual advance oaks must be relatively large with well-established root systems before they will compete successfully and be dominant in...

Accelerating the kiln drying of oak

Treesearch

William T. Simpson

1980-01-01

Reducing kiln-drying time for oak lumber can reduce energy requirements as well as reduce lumber inventories. In this work, l-inch northern red oak and white oak were kiln dried from green by a combination of individual accelerating techniques– presurfacing, presteaming, accelerated and smooth schedule, and high-temperature drying below 18 percent moisture content....

Mammal caching of oak acorns in a red pine and a mixed oak stand

Treesearch

E.R. Thorn; W.M. Tzilkowski

1991-01-01

Small mammal caching of oak (Quercus spp.) acorns in adjacent red pine (Pinus resinosa) and mixed-oak stands was investigated at The Penn State Experimental Forest, Huntingdon Co., Pennsylvania. Gray squirrels (Sciurus carolinensis) and mice (Peromyscus spp.) were the most common acorn-caching...

Protecting Trees from Sudden Oak Death before Infection

Treesearch

C. Lee; Y. Valachovic; M. Garbelotto

2010-01-01

Phytophthora ramorum, an introduced invasive plant pathogen that causes sudden oak death, has killed over a million tanoak, coast live oak, Shreve oak, and California black oak trees along the California coastal region from Monterey through Humboldt Counties. Most trees infected with P. ramorum will eventually die, including...

Coast live oak, Quercus agrifolia, susceptibility and response to goldspotted oak borer, Agrilus auroguttatus, injury in southern California

Treesearch

Tom W. Coleman; Nancy E. Grulke; Miles Daly; Cesar Godinez; Susan L. Schilling; Philip J. Riggan; Steven J. Seybold

2011-01-01

Oak mortality is often associated with a complex of decline factors. We describe the morphological and physiological responses of coast live oak, Quercus agrifolia Née, in California to an invasive insect, the goldspotted oak borer (GSOB), Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), and evaluate drought as a...

Working and Learning Among California Oaks

NASA Astrophysics Data System (ADS)

Tietje, B.; Gingg, B.; Zingo, J.; Huntsinger, L.

2009-04-01

With tremendous support from collaborators and enthusiastic volunteers, "Learning Among the Oaks" at the historic Santa Margarita Ranch has become a favorite outdoor learning experience for hundreds of Santa Margarita School students, along with their teachers and families. Oaks are at the center of this unique and cost effective public education program. From getting to know local oaks to exploring conservation issues within the context of a historic working cattle ranch, students take pride in expanding their awareness and knowledge of the local oak woodland community. Santa Margarita School families representing the varied demographics of the community come together on the trail. For many, the program provides a first opportunity to get to know those who make a living on the land and to understand that this land around their school is more than a pretty view. "Learning Among the Oaks" also addresses the need for quality, hands-on science activities and opportunities to connect children with the outdoor world. Using a thematic approach and correlating lessons with State Science Standards, we've engaged students in a full-spectrum of exciting outdoor learning adventures. As students progress through the grades, they find new challenges within the oak trail environment. We've succeeded in establishing an internship program that brings highly qualified, enthusiastic university students out to practice their science teaching skills while working with elementary school students. In the future, these university student interns may assist with the development of interpretive displays, after-school nature activities and monitoring projects. We've benefited from proximity to Cal Poly State University and its "learn-by-doing" philosophy. We've also succeeded in building a dedicated network of volunteers and collaborators, each with a special interest satisfied through participation in the oak trail program. While "Learning Among the Oaks" has focused on educating school

MicroRNA expression profiling during the life cycle of the silkworm (Bombyx mori)

PubMed Central

Liu, Shiping; Zhang, Liang; Li, Qibin; Zhao, Ping; Duan, Jun; Cheng, Daojun; Xiang, Zhonghuai; Xia, Qingyou

2009-01-01

Background MicroRNAs (miRNAs) are expressed by a wide range of eukaryotic organisms, and function in diverse biological processes. Numerous miRNAs have been identified in Bombyx mori, but the temporal expression profiles of miRNAs corresponding to each stage transition over the entire life cycle of the silkworm remain to be established. To obtain a comprehensive overview of the correlation between miRNA expression and stage transitions, we performed a whole-life test and subsequent stage-by-stage examinations on nearly one hundred miRNAs in the silkworm. Results Our results show that miRNAs display a wide variety of expression profiles over the whole life of the silkworm, including continuous expression from embryo to adult (miR-184), up-regulation over the entire life cycle (let-7 and miR-100), down-regulation over the entire life cycle (miR-124), expression associated with embryogenesis (miR-29 and miR-92), up-regulation from early 3rd instar to pupa (miR-275), and complementary pulses in expression between miR-34b and miR-275. Stage-by-stage examinations revealed further expression patterns, such as emergence at specific time-points during embryogenesis and up-regulation of miRNA groups in late embryos (miR-1 and bantam), expression associated with stage transition between instar and molt larval stages (miR-34b), expression associated with silk gland growth and spinning activity (miR-274), continuous high expression from the spinning larval to pupal and adult stages (miR-252 and miR-31a), a coordinate expression trough in day 3 pupae of both sexes (miR-10b and miR-281), up-regulation in pupal metamorphosis of both sexes (miR-29b), and down-regulation in pupal metamorphosis of both sexes (miR-275). Conclusion We present the full-scale expression profiles of miRNAs throughout the life cycle of Bombyx mori. The whole-life expression profile was further investigated via stage-by-stage analysis. Our data provide an important resource for more detailed functional

MicroRNA expression profiling during the life cycle of the silkworm (Bombyx mori).

PubMed

Liu, Shiping; Zhang, Liang; Li, Qibin; Zhao, Ping; Duan, Jun; Cheng, Daojun; Xiang, Zhonghuai; Xia, Qingyou

2009-09-28

MicroRNAs (miRNAs) are expressed by a wide range of eukaryotic organisms, and function in diverse biological processes. Numerous miRNAs have been identified in Bombyx mori, but the temporal expression profiles of miRNAs corresponding to each stage transition over the entire life cycle of the silkworm remain to be established. To obtain a comprehensive overview of the correlation between miRNA expression and stage transitions, we performed a whole-life test and subsequent stage-by-stage examinations on nearly one hundred miRNAs in the silkworm. Our results show that miRNAs display a wide variety of expression profiles over the whole life of the silkworm, including continuous expression from embryo to adult (miR-184), up-regulation over the entire life cycle (let-7 and miR-100), down-regulation over the entire life cycle (miR-124), expression associated with embryogenesis (miR-29 and miR-92), up-regulation from early 3rd instar to pupa (miR-275), and complementary pulses in expression between miR-34b and miR-275. Stage-by-stage examinations revealed further expression patterns, such as emergence at specific time-points during embryogenesis and up-regulation of miRNA groups in late embryos (miR-1 and bantam), expression associated with stage transition between instar and molt larval stages (miR-34b), expression associated with silk gland growth and spinning activity (miR-274), continuous high expression from the spinning larval to pupal and adult stages (miR-252 and miR-31a), a coordinate expression trough in day 3 pupae of both sexes (miR-10b and miR-281), up-regulation in pupal metamorphosis of both sexes (miR-29b), and down-regulation in pupal metamorphosis of both sexes (miR-275). We present the full-scale expression profiles of miRNAs throughout the life cycle of Bombyx mori. The whole-life expression profile was further investigated via stage-by-stage analysis. Our data provide an important resource for more detailed functional analysis of miRNAs in this animal.

Establishment patterns of Oregon white oak and California black oak woodlands in northwestern California

Treesearch

Madelinn Schriver; Rosemary Sherriff

2015-01-01

Mixed-Oregon white oak (Quercus garryana) and California black oak (Q. kelloggii) woodlands are unique ecosystems that support high biodiversity in the Pacific Northwest, yet little is known about their current and historical stand establishment patterns in northwestern California. With concerns of local extirpation due to...

Transpiration of oak trees in the oak savannas of the Southwestern Borderlands region

Treesearch

Peter F. Ffolliott; Cody L. Stropki; Aaron T. Kauffman; Gerald J. Gottfried

2008-01-01

Transpiration of oak trees on the Cascabel watersheds in the savannas on the eastern slope of the Peloncillo Mountains in southwestern New Mexico has been estimated by the sap-flow method. Transpiration represents the largest loss of gross precipitation falling on a watershed in approximations of water budgets for the more densely stocked oak woodlands of the...

Diversity in copy number and structure of a silkworm morphogenetic gene as a result of domestication.

PubMed

Sakudoh, Takashi; Nakashima, Takeharu; Kuroki, Yoko; Fujiyama, Asao; Kohara, Yuji; Honda, Naoko; Fujimoto, Hirofumi; Shimada, Toru; Nakagaki, Masao; Banno, Yutaka; Tsuchida, Kozo

2011-03-01

The carotenoid-binding protein (CBP) of the domesticated silkworm, Bombyx mori, a major determinant of cocoon color, is likely to have been substantially influenced by domestication of this species. We analyzed the structure of the CBP gene in multiple strains of B. mori, in multiple individuals of the wild silkworm, B. mandarina (the putative wild ancestor of B. mori), and in a number of other lepidopterans. We found the CBP gene copy number in genomic DNA to vary widely among B. mori strains, ranging from 1 to 20. The copies of CBP are of several types, based on the presence of a retrotransposon or partial deletion of the coding sequence. In contrast to B. mori, B. mandarina was found to possess a single copy of CBP without the retrotransposon insertion, regardless of habitat. Several other lepidopterans were found to contain sequences homologous to CBP, revealing that this gene is evolutionarily conserved in the lepidopteran lineage. Thus, domestication can generate significant diversity of gene copy number and structure over a relatively short evolutionary time. © 2011 by the Genetics Society of America

Diversity in Copy Number and Structure of a Silkworm Morphogenetic Gene as a Result of Domestication

PubMed Central

Sakudoh, Takashi; Nakashima, Takeharu; Kuroki, Yoko; Fujiyama, Asao; Kohara, Yuji; Honda, Naoko; Fujimoto, Hirofumi; Shimada, Toru; Nakagaki, Masao; Banno, Yutaka; Tsuchida, Kozo

2011-01-01

The carotenoid-binding protein (CBP) of the domesticated silkworm, Bombyx mori, a major determinant of cocoon color, is likely to have been substantially influenced by domestication of this species. We analyzed the structure of the CBP gene in multiple strains of B. mori, in multiple individuals of the wild silkworm, B. mandarina (the putative wild ancestor of B. mori), and in a number of other lepidopterans. We found the CBP gene copy number in genomic DNA to vary widely among B. mori strains, ranging from 1 to 20. The copies of CBP are of several types, based on the presence of a retrotransposon or partial deletion of the coding sequence. In contrast to B. mori, B. mandarina was found to possess a single copy of CBP without the retrotransposon insertion, regardless of habitat. Several other lepidopterans were found to contain sequences homologous to CBP, revealing that this gene is evolutionarily conserved in the lepidopteran lineage. Thus, domestication can generate significant diversity of gene copy number and structure over a relatively short evolutionary time. PMID:21242537

HOW to Identify, Prevent, and Control Oak Wilt

Treesearch

Joseph O' Brien; Manfred Mielke; Dale Starkey; Jennifer Juzwik

2000-01-01

Oak wilt is an aggressive disease that affects many species of oak (Quercus spp.). It is one of the most serious tree diseases in the eastern United States, killing thousands of oaks each year in forests, woodlots, and home landscapes. Oak wilt was first identified in 1944. The fungal pathogen that causes the disease, Ceratocystis fagacearum, is thought by...

Response of chestnut oak and red oak to drought and fertilization: growth and physiology

Treesearch

M.D. Kleiner; M.D. Abrams; J.C. Schultz

1991-01-01

Chestnut oak (Quercus prinus L.) and red oak (Quercus rubra L.) seedlings were grown for two seasons under two nutrient regimes: fertilizer + (NPK) and fertilizer - (No NPK). Beginning two weeks after budbreak, water was withheld for 10 weeks during the second growing season. Leaf water potentials, gas exchange measurements and...

New relationships among the sudden oak death pathogen, bark and ambrosia beetles, and fungi colonizing coast live oaks

Treesearch

Nadir Erbilgin; Brice A. McPherson; Pierluigi Bonello; David L. Wood; Andrew J. Nelson

2008-01-01

Sudden oak death (SOD) has had devastating effects on several oak species in many California coastal forests. Phytophthora ramorum has been identified as the primary causal agent of sudden oak death. While the pathogen may be capable of killing mature trees, it is likely that in nature opportunistic organisms play significant roles in the decline and...

Interrelations of green oak leaf roller population and common oak: results of 30-year monitoring and mathematical modeling

Treesearch

V. V. Rubtsov; I. A. Utkina

2003-01-01

Long-term monitoring followed by mathematical modeling was used to describe the population dynamics of the green oak leaf roller Tortrix viridana L. over a period of 30 years and to study reactions of oak stands to different levels of defoliation. The mathematical model allows us to forecast the population dynamics of the green oak leaf roller and...

A meta-analysis of the fire-oak hypothesis: Does prescribed burning promote oak reproduction in eastern North America

Treesearch

Patrick H. Brose; Daniel C. Dey; Ross J. Phillips; Thomas A. Waldrop

2013-01-01

The fire-oak hypothesis asserts that the current lack of fire is a reason behind the widespread oak (Quercus spp.) regeneration difficulties of eastern North America, and use of prescribed burning can help solve this problem. We performed a meta-analysis on the data from 32 prescribed fire studies conducted in mixed-oak forests to test whether they...

The Use of Soil Scarification to Enhance Oak Regeneration in a Mixed-Oak Bottomland Forest of Southern Illinois

Treesearch

John M. Lhotka; James J. Zaczek

2002-01-01

The purpose of the study was to investigate whether soil scarification following seed fall can be used to increase the density of oak regeneration in a mixed-oak stand. The study area was a 4.5-hectare stand dominated by cherrybark oak (Quercus pagoda Eli.). The understory had a high percent cover of poison ivy (Toxicodendron radicans...

Absorption of mulberry root urease to the hemolymph of the silkworm, Bombyx mori.

PubMed

Kurahashi, Hitoshi; Atiwetin, Panida; Nagaoka, Sumiharu; Miyata, Seiji; Kitajima, Sakihito; Sugimura, Yukio

2005-09-01

Mulberry leaves are the sole diet of the silkworm, Bombyx mori. The host urease is incorporated into the larval hemolymph and involved in nitrogen metabolism in the insect. To investigate the selective absorption of the host urease to the larvae, crude urease was prepared from mulberry leaves and roots. Root urease was identical to leaf urease on the basis of electrophoretic analyses: (1) the urease activity appeared in the same migration position in a native gel; (2) There was no difference in molecular mass of the subunit. The root urease was orally injected to the fifth instar larvae of the silkworm. Just before spinning, the larvae absorbed intact urease from the midgut lumen to the hemolymph without the loss of activity. The capacity to absorb urease occurred only at the specific stage. Localization of host urease in midgut tissue was observed using confocal laser scanning microscopy and transmission electron microscopy. Based on spatial distribution of immunofluorescent signals and immunogold particles, host urease specifically attached to the surfaces of microvilli existing in the apical side of columnar cells and appeared in the cytoplasm of the cells for transport to the hemolymph. The incorporation efficiency of root urease into the hemolymph was significantly higher than for ureases from jack bean seeds and Bacillus pasteurii. The urease that was transported to the hemolymph was electrophoretically altered, compared with the host urease extracted.

Resistance to BmNPV via Overexpression of an Exogenous Gene Controlled by an Inducible Promoter and Enhancer in Transgenic Silkworm, Bombyx mori

PubMed Central

Jiang, Liang; Cheng, Tingcai; Zhao, Ping; Yang, Qiong; Wang, Genhong; Jin, Shengkai; Lin, Ping; Xiao, Yang; Xia, Qingyou

2012-01-01

The hycu-ep32 gene of Hyphantria cunea NPV can inhibit Bombyx mori nucleopolyhedrovirus (BmNPV) multiplication in co-infected cells, but it is not known whether the overexpression of the hycu-ep32 gene has an antiviral effect in the silkworm, Bombyx mori. Thus, we constructed four transgenic vectors, which were under the control of the 39 K promoter of BmNPV (39 KP), Bombyx mori A4 promoter (A4P), hr3 enhancer of BmNPV combined with 39 KP, and hr3 combined with A4P. Transgenic lines were created via embryo microinjection using practical diapause silkworm. qPCR revealed that the expression level of hycu-ep32 could be induced effectively after BmNPV infection in transgenic lines where hycu-ep32 was controlled by hr3 combined with 39 KP (i.e., HEKG). After oral inoculation of BmNPV with 3 × 105 occlusion bodies per third instar, the mortality with HEKG-B was approximately 30% lower compared with the non-transgenic line. The economic characteristics of the transgenic lines remained unchanged. These results suggest that overexpression of an exogenous antiviral gene controlled by an inducible promoter and enhancer is a feasible method for breeding silkworms with a high antiviral capacity. PMID:22870254

Effects of Ag Nanoparticles on Growth and Fat Body Proteins in Silkworms (Bombyx mori).

PubMed

Meng, Xu; Abdlli, Nouara; Wang, Niannian; Lü, Peng; Nie, Zhichao; Dong, Xin; Lu, Shuang; Chen, Keping

2017-12-01

Ag nanoparticles (AgNPs), a widely used non-antibiotic, antibacterial material, have shown toxic and other potentially harmful effects in mammals. However, the deleterious effects of AgNPs on insects are still unknown. Here, we studied the effects of AgNPs on the model invertebrate organism Bombyx mori. After feeding silkworm larvae different concentrations of AgNPs, we evaluated the changes of B. mori body weights, survival rates, and proteomic differences. The results showed that low concentrations (<400 mg/L) of AgNPs promoted the growth and cocoon weights of B. mori. Although high concentrations (≥800 mg/L) of AgNPs also improved B. mori growth, they resulted in silkworm death. An analysis of fat body proteomic differences revealed 13 significant differences in fat body protein spots, nine of which exhibited significantly downregulated expression, while four showed significantly upregulated expression. Reverse transcription-polymerase chain reaction results showed that at an AgNP concentration of 1600 mg/L, the expression levels of seven proteins were similar to the transcription levels of their corresponding genes. Our results suggest that AgNPs lowered the resistance to oxidative stress, affected cell apoptosis, and induced cell necrosis by regulating related protein metabolism and metabolic pathways in B. mori.

Molecular and Physiological Characterization of Two Novel Multirepeat β-Thymosins from Silkworm, Bombyx mori

PubMed Central

Lü, Peng; Yang, Yanhua; Yao, Qin; Xia, Hengchuan; Chen, Keping

2015-01-01

β-thymosin plays important roles in the development of the lymphatic system and the central nervous system in vertebrates. However, its role and function in invertebrates remain much less explored. Here, we firstly isolated a gene encoding β-thymosin in silkworm (Bombyx mori L.). Interestingly, this gene encodes two polypeptides, named as BmTHY1 and BmTHY2, via two different modes of RNA splicing. The recombinant proteins fused with an N-term GST tag were over-expressed in Escherichia coli (E. coli) and further purified to near homogenity to prepare mouse antibodies. The Western blot analysis showed that these proteins were expressed in various tissues and organs, as well as in different developmental stages. Amazingly, the expression of BmTHY2 was hugely increased during the pupae stage, indicating a specialized role in this period. The expression of these proteins was gradually decreased in BmN cells infected by BmNPV, suggesting they may play different roles in the virus infection. In addition, both BmTHY1 and BmTHY2 can interact with 14-3-3 of silkworm and Ubiquitin of BmNPV as shown by GST pull down and Co-IP assays, consistent with their roles in the regulation of the development of nervous system. PMID:26474303

Efficacy of Alamo for prophylactic and therapeutic treatment of oak wilt in red oaks, 2004

Treesearch

K. Ward; J. Juzwik; S. Bernick

2004-01-01

An experiment (prophylactic study) to determine the efficacy of Alamo in preventing spread of C. fagacearum through grafted roots of oak wilt-affected and of apparently healthy red oaks was initiated in eight locations in east-central and southeastern Minnesota in Jul 2002.

Auger planting of oak seedlings in northern Arkansas

Treesearch

Eric Heitzman; Adrian Grell

2003-01-01

Planting oak seedlings to regenerate upland oak forests is a promising but untested silvicultural practice in the Ozark Mountains of northern Arkansas. The stony (cherty) soils of the region make it difficult to dig deep planting holes using conventional hand planting tools. In 2001, we planted 1-0 northern red oak and white oak seedlings in 0.5 to 1 acre group...

The supply and demand situation for oak timber

Treesearch

Kenneth L. Quigley

1971-01-01

Twenty oak species in the eastern United States account for one-third of the hardwood sawtimber volume and almost 10 percent of both hardwood and softwood growing-stock volume. The oak-hickory and oak-pine forest types occupy about 38 percent of the forest land in the eastern United States. Oak timber volume is increasing. Annual growth exceeds annual removals by about...

Relative susceptibility of oaks to seven species of Phytophthora isolated from oak forest soils

Treesearch

Y. Balci; S. Balci; W.L. MacDonald; K.W. Gottschalk

2008-01-01

Isolates of Phytophthora cambivora, P. cinnamomi, P. citricola, P. europaea, P. quercetorum and two unidentified species were tested for their pathogenicity to eastern US oak species by root and stem inoculations. Experiments were conducted during two different periods and included 1-, 2- and 20- year-old oaks grown under greenhouse and field...

Comprehensive integrated planning: A process for the Oak Ridge Reservation, Oak Ridge, Tennessee

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

NONE

1998-05-01

The Oak Ridge Comprehensive Integrated Plan is intended to assist the US Department of Energy (DOE) and contractor personnel in implementing a comprehensive integrated planning process consistent with DOE Order 430.1, Life Cycle Asset Management and Oak Ridge Operations Order 430. DOE contractors are charged with developing and producing the Comprehensive Integrated Plan, which serves as a summary document, providing information from other planning efforts regarding vision statements, missions, contextual conditions, resources and facilities, decision processes, and stakeholder involvement. The Comprehensive Integrated Plan is a planning reference that identifies primary issues regarding major changes in land and facility use andmore » serves all programs and functions on-site as well as the Oak Ridge Operations Office and DOE Headquarters. The Oak Ridge Reservation is a valuable national resource and is managed on the basis of the principles of ecosystem management and sustainable development and how mission, economic, ecological, social, and cultural factors are used to guide land- and facility-use decisions. The long-term goals of the comprehensive integrated planning process, in priority order, are to support DOE critical missions and to stimulate the economy while maintaining a quality environment.« less

Understanding the nano- and macromechanical behaviour, the failure and fatigue mechanisms of advanced and natural polymer fibres by Raman/IR microspectrometry

NASA Astrophysics Data System (ADS)

Colomban, Philippe

2013-03-01

The coupled mechanical and Raman/infrared (IR) analysis of the (nano)structure and texture of synthetic and natural polymer fibres (polyamides (PA66), polyethylene terephthalate (PET), polypropylene (PP), poly(paraphenylene benzobisoxazole) (PBO), keratin/hair, Bombyx mori, Gonometa rufobrunea/postica Antheraea/Tussah silkworms and Nephila Madagascarensis spider silks) is applied so as to differentiate between crystalline and amorphous macromolecules. Bonding is very similar in the two cases but a broader distribution of conformations is observed for the amorphous macromolecules. These conclusions are then used to discuss the modifications induced by the application of a tensile or compressive stress, including the effects of fatigue. Detailed attention is paid to water and the inter-chain coupling for which the importance of hydrogen bonding is reconsidered. The significant role of the ‘amorphous’ bonds/domains in the process of fracture/fatigue is shown. Invited talk at the 6th International Workshop on Advanced Materials Science and Nanotechnology IWAMSN2012, 30 October-2 November 2012, Ha Long, Vietnam.

Iowa's oldest oaks. [Quercus alba

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

Duvick, D.N.; Blasing, T.J.

1983-01-01

Tree-ring analysis revealed 33 living white oaks (Quercus alba) in Iowa that began growing before 1700. Core of wood 4 mm in diameter, each extracted from a radius of a tree trunk were analyzed. The oldest white oak, found in northeastern Warren County, began growing about 1570 and is thus over 410 years old. A chinkapin oak (Quercus muehlenbergii) was also found which was more than 300 years old. Ring widths from the white oaks are well correlated with total precipitation for the twelve months preceding completion of ring formation in July. Reconstructions of annual (August-July) precipitation for 1680-1979, basedmore » on the tree rings, indicate that the driest annual period in Iowa was August 1799-July 1800, and that the driest decade began about 1816. Climatic information of this kind, pre-dating written weather records, can be used to augment those records and provide a longer baseline of information for use by climatologists and hydrologic planners.« less

Oak Decline and Red Oak Borer in the Interior Highlands of Arkansas an Missouri: Natural Phenomena, Severe Occurrences

Treesearch

Dale A. Starkey; Forrest Oliveria; Alexander Mangini; Manfred Mielke

2004-01-01

Oak decline is a complex disease resulting in dieback and mortality of oaks. A number of factors are involved and can be classified as predisposing, inciting, or contributing, according to their roles. Decline events have been noted repeatedly during the past century in the eastern U.S. A severe episode of oak decline is occurring in the Interior Highlands region of...

Properties of a recombinant bovine tissue factor expressed by Silkworm pupae and its performance as an Owren-type prothrombin time reagent for warfarin monitoring.

PubMed

Okuda, Masahiro; Taniguchi, Tomokuni; Takamiya, Osamu

2012-09-01

Tissue factor (TF), or thromboplastin, is a glycoprotein that triggers the extrinsic coagulation pathway. In blood coagulation testing, TF has been used as a natural source for determining Quick prothrombin time (PT) or the Owren PT (OBT). Currently, natural sources are being replaced with recombinant proteins because of their uniform characteristics and the possibility of stable mass production of PT reagents. Because bovine spongiform encephalopathy (BSE)-infected cows are widespread in Japan, we prepared a recombinant bovine TF (rbTF) with a baculovirus expression system using silkworms. To overcome the limitations of natural TF, especially in bovine brain, we expressed a full-length rbTF protein in Silkworm pupae with a baculovirus expression system. Baculovirus inactivation and the presence of DNA fragments in the rbTF fraction were confirmed using Reed-Muench and polymerase chain reaction methods after inactivation with a detergent. The rbTF fraction prepared by an immobilized anti-Silkworm pupae fluid protein Sepharose 4B column was identified as a visible band on western blots with a polyclonal antibody against human TF with cross-reactivity with TFs. The inhibition of the polyclonal antibody against human TF by the clotting assay for PT was identified, and amidolytic biological activity through activated factor VII on S-2288 substrate was observed. In conclusion, the rbTF expressed by the baculovirus system using Silkworm pupae was uniformly specific for bovine TF. The OBT reagent incorporated by this rbTF was similar to those of commercial reagents. It also showed a suitable International Sensitivity Index and reproducibility precision, thereby allowing for diagnostic use. Copyright © 2012 Elsevier Ltd. All rights reserved.

Comparison of oak and sugar maple distribution and regeneration in central Illinois upland oak forests

Treesearch

Peter J. Frey; Scott J. Meiners

2014-01-01

Changes in disturbance frequencies, habitat fragmentation, and other biotic pressures are allowing sugar maple (Acer saccharum) to displace oak (Quercus spp.) in the upland forest understory. The displacement of oaks by sugar maples represents a major management concern throughout the region. We collected seedling microhabitat data...

An ecologically based approach to oak silviculture: a synthesis of 50 years of oak ecosystem research in North America

Treesearch

Daniel C. Dey; Alejandro A. Royo; Patrick H. Brose; Todd F. Hutchinson; Martin A. Spetich; Scott H. Stoleson

2010-01-01

Oak (Quercus L.) is an abundant and widely distributed genus in eastern North America. A history of periodic fire, grazing, canopy disturbance and timber harvesting has favored oak's dominance. But, changes in this regime toward much less fire or complete fire suppression, and selective cutting are causing the successional replacement of oak....

Cloning and Expression Analysis of the Bombyx mori α-amylase Gene (Amy) from the Indigenous Thai Silkworm Strain, Nanglai

PubMed Central

Ngernyuang, Nipaporn; Kobayashi, Isao; Promboon, Amornrat; Ratanapo, Sunanta; Tamura, Toshiki; Ngernsiri, Lertluk

2011-01-01

α-Amylase is a common enzyme for hydrolyzing starch. In the silkworm, Bombyx mori L. (Lepidoptera: Bombycidae), α-amylase is found in both digestive fluid and hemolymph. Here, the complete genomic sequence of the Amy gene encoding α-amylase from a local Thai silkworm, the Nanglai strain, was obtained. This gene was 7981 bp long with 9 exons. The full length Amy cDNA sequence was 1749 bp containing a 1503 bp open reading frame. The ORF encoded 500 amino acid residues. The deduced protein showed 81–54% identity to other insect α-amylases and more than 50% identity to mammalian enzymes. Southern blot analysis revealed that in the Nanglai strain Amy is a single-copy gene. RT- PCR showed that Amy was transcribed only in the foregut. Transgenic B. mori also showed that the Amy promoter activates expression of the transgene only in the foregut. PMID:21529256

Fire in upper Midwestern oak forest ecosystems: an oak forest restoration and management handbook

Treesearch

Lee E. Frelich; Peter B. Reich; David W. Peterson

2015-01-01

We reviewed the literature to synthesize what is known about the use of fire to maintain and restore oak forests, woodlands, and savannas of the upper Midwestern United States, with emphasis on Minnesota, Wisconsin, and Michigan. Included are (1) known physical and ecological effects of fire on oaks from acorn through seedling, established sapling, and mature stages of...

Proceedings of the seventh California oak symposium: managing oak woodlands in a dynamic world

Treesearch

Richard B. Standiford; Kathryn L. Purcell

2015-01-01

Beginning in 1979, there have been a series of symposia held every 5 to 7 years addressing the state of our knowledge about science, policy and management factors affecting California's oak resource. This program represents the seventh symposium in the series. California's oak woodlands cover 10 percent of the state, and in addition, are a key ecological...

Oak Regeneration Using the Two-Age System

Treesearch

Jeffrey W. Stringer

2002-01-01

The two studies presented in this paper were completed in southeastern Kentucky and were designed to evaluate acorn production and development of advanced white oak reproduction from fully released white oak (Quercus alba) trees typical of reserve trees in the two age system. Twelve 2 acre 60- to 90-year-old white oak dominated stands were...

Response of Overtopped White Oak to Release

Treesearch

Charles E. McGee

1981-01-01

Pole sized white oaks increase in volume growth following release from overtopping trees, but the response varies by size, age and appearance of the oaks. Significant increases in epicormic sprouting, height loss by some released trees, and highly variable stem volume growth make overtopped white oak a very questionable source of future crop trees. If overtopped trees...

Oaks belowground: mycorrhizas, truffles, and small mammals

Treesearch

Jonathan Frank; Seth Barry; Joseph Madden; Darlene Southworth

2008-01-01

Oaks depend on hidden diversity belowground. Oregon white oaks (Quercus garryana) form ectomycorrhizas with more than 40 species of fungi at a 25-ha site. Several of the most common oak mycorrhizal fungi form hypogeous fruiting bodies or truffles in the upper layer of mineral soil. We collected 18 species of truffles associated with Oregon white...

Site and canopy characteristics associated with oak advance reproduction in mature oak-hickory forests in the ridge and valley province in Tennessee

Treesearch

Leslie S. Chadwell; David S. Buckley

2003-01-01

To investigate hypotheses regarding effects of competitors and site quality on oak regeneration, we documented site factors and oak seedling composition, size, and abundance in the Ridge and Valley Province of Tennessee. Small oak seedlings were most abundant on productive soils and mesic landform positions, whereas large oak seedlings were most abundant on less...

Oak decline

Treesearch

Kenneth J., Jr. Kessler; David R. Houston

1989-01-01

Oak declines are complex plant diseases that result when trees are first stressed by environmental factors and/or living organisms and are then invaded and sometimes killed by opportunistic secondary organisms.

Oak Regeneration - What We Know

Treesearch

Harvey E. Kennedy

1989-01-01

Growth and development of saplings of four-oak (Quercus spp.) species planted at five spacings in a minor stream bottom in southeast Arkansas showed significant differences among species and spacings. Spacing affected all tree size and biomass variables except survival. Yater oak (Q. nigra L.) developed most rapidly; swamp chestnut...

Monitoring oak-hickory forest change during an unprecedented red oak borer outbreak in the Ozark Mountains: 1990 to 2006

Treesearch

Joshua S. Jones; Jason A. Tullis; Laurel J. Haavik; James M. Guldin; Fred M. Stephen

2014-01-01

Upland oak-hickory forests in Arkansas, Missouri, and Oklahoma experienced oak decline in the late 1990s and early 2000s during an unprecedented outbreak of a native beetle, the red oak borer (ROB), Enaphalodes rufulus (Haldeman). Although remote sensing supports frequent monitoring of continuously changing forests, comparable in situ observations are critical for...

Transcriptome analysis of the epidermis of the purple quail-like (q-lp) mutant of silkworm, Bombyx mori.

PubMed

Wang, Pingyang; Qiu, Zhiyong; Xia, Dingguo; Tang, Shunming; Shen, Xingjia; Zhao, Qiaoling

2017-01-01

A new purple quail-like (q-lp) mutant found from the plain silkworm strain 932VR has pigment dots on the epidermis similar to the pigment mutant quail (q). In addition, q-lp mutant larvae are inactive, consume little and grow slowly, with a high death rate and other developmental abnormalities. Pigmentation of the silkworm epidermis consists of melanin, ommochrome and pteridine. Silkworm development is regulated by ecdysone and juvenile hormone. In this study, we performed RNA-Seq on the epidermis of the q-lp mutant in the 4th instar during molting, with 932VR serving as the control. The results showed 515 differentially expressed genes, of which 234 were upregulated and 281 downregulated in q-lp. BLASTGO analysis indicated that the downregulated genes mainly encode protein-binding proteins, membrane components, oxidation/reduction enzymes, and proteolytic enzymes, whereas the upregulated genes largely encode cuticle structural constituents, membrane components, transport related proteins, and protein-binding proteins. Quantitative reverse transcription PCR was used to verify the accuracy of the RNA-Seq data, focusing on key genes for biosynthesis of the three pigments and chitin as well as genes encoding cuticular proteins and several related nuclear receptors, which are thought to play key roles in the q-lp mutant. We drew three conclusions based on the results: 1) melanin, ommochrome and pteridine pigments are all increased in the q-lp mutant; 2) more cuticle proteins are expressed in q-lp than in 932VR, and the number of upregulated cuticular genes is significantly greater than downregulated genes; 3) the downstream pathway regulated by ecdysone is blocked in the q-lp mutant. Our research findings lay the foundation for further research on the developmental changes responsible for the q-lp mutant.

Clemson Researchers Find Prescribed Fire Regenerates Oak Forests

Treesearch

David van Lear; Patrick Brose

1999-01-01

Fire is being prescribed by Clemson University forestry researchers to regenerate oak forests. Regenerating oaks following timber harvests is a major challenge because faster growing yellow polar and red maple trees crowd out hte more valuable oak seedlings.

Mutation of a vitelline membrane protein, BmEP80, is responsible for the silkworm "Ming" lethal egg mutant.

PubMed

Chen, Anli; Gao, Peng; Zhao, Qiaoling; Tang, Shunming; Shen, Xingjia; Zhang, Guozheng; Qiu, Zhiyong; Xia, Dingguo; Huang, Yongping; Xu, Yunmin; He, Ningjia

2013-02-25

The egg stage is an important stage in the silkworm (Bombyx mori) life cycle. Normal silkworm eggs are usually short, elliptical, and laterally flattened, with a sometimes hollowed surface on the lateral side. However, the eggs laid by homozygous recessive "Ming" lethal egg mutants (l-e(m)) lose water and become concaved around 1h, ultimately exhibiting a triangular shape on the egg surfaces. We performed positional cloning, and narrowed down the region containing the gene responsible for the l-e(m) mutant to 360 kb on chromosome 10 using 2287 F(2) individuals. Using expression analysis and RNA interference, the best l-e(m) candidate gene was shown to be BmEP80. The results of the inverse polymerase chain reaction showed that an ~1.9 kb region from the 3' untranslated region of BmVMP23 to the forepart of BmEP80 was replaced by a >100 kb DNA fragment in the l-e(m) mutant. Several eggs laid by the normal moths injected with BmEP80 small interfering RNAs were evidently depressed and exhibited a triangular shape on the surface. The phenotype exhibited was consistent with the eggs laid by the l-e(m) mutant. Moreover, two-dimensional gel electrophoresis showed that the BmEP80 protein was expressed in the ovary from the 9th day of the pupa stage to eclosion in the wild-type silkworm, but was absent in the l-e(m) mutant. These results indicate that BmEP80 is responsible for the l-e(m) mutation. Copyright © 2012 Elsevier B.V. All rights reserved.

Seeding and planting upland oaks

Treesearch

T. E. Russell

1971-01-01

Upland oaks can be established by seeding or planting, but additional experience is needed before these methods become economical alternatives to natural regeneration. Recently forested sites are generally more favorable than abandoned fields. Lack of repellents to protect acorns from animals severely limits direct seeding, but oaks can be planted readily by...

Silkworm Thermal Biology: A Review of Heat Shock Response, Heat Shock Proteins and Heat Acclimation in the Domesticated Silkworm, Bombyx mori

PubMed Central

Manjunatha, H. B.; Rajesh, R. K.; Aparna, H. S.

2010-01-01

Heat shock proteins (HSPs) are known to play ecological and evolutionary roles in this postgenomic era. Recent research suggests that HSPs are implicated in cardiovascular biology and disease development, proliferation and regulation of cancer cells, cell death via apoptosis, and several other key cellular functions. These activities have generated great interest amongst cell and molecular biologists, and these biologists are keen to unravel other hitherto unknown potential functions of this group of proteins. Consequently, the biological significance of HSPs has led to cloning and characterization of genes encoding HSPs in many organisms including the silkworm, Bombyx mori L. (Lepidoptera: Bombycidae). However, most of the past investigations in B. mori were confined to expression of HSPs in tissues and cell lines, whereas information on their specific functional roles in biological, physiological, and molecular processes is scarce. Naturally occurring or domesticated polyvoltines (known to be the tropical race) are more resistant to high temperatures and diseases than bi- or univoltines (temperate races). The mechanism of ecological or evolutionary modification of HSPs during the course of domestication of B. mori - particularly in relation to thermotolerance in geographically distinct races/strains - is still unclear. In addition, the heat shock response, thermal acclimation, and hardening have not been studied extensively in B. mori compared to other organisms. Towards this, recent investigations on differential expression of HSPs at various stages of development, considering the concept of the whole organism, open ample scope to evaluate their biological and commercial importance in B. mori which has not been addressed in any of the representative organisms studied so far. Comparatively, heat shock response among different silkworm races/strains of poly-, bi-, and univoltines varies significantly and thermotolerance increases as the larval development proceeds

Manufacture of industrial products from oak

Treesearch

Hugh W. Reynolds

1971-01-01

The three largest and fastest growing markets for oak are railroad crossties, reusable pallets, and truck and container flooring. Manufacturers of oak lumber are advised to keep these products in mind when planning their production.

Forecasting the future of coast live oak forests in the face of sudden oak death

Treesearch

Letty B. Brown; Barbara Allen-Diaz

2006-01-01

Little is known about the potential short- and long-term impacts of sudden oak death (SOD) on forest structure and composition. This study began in 2002 to evaluate the effects of SOD on coast live oak (Quercus agrifolia) - California bay laurel (Umbellularia californica) forests over a gradient of Phytophthora ramorum...

Relationships between Phytophthora ramorum canker (sudden oak death) and failure potential in coast live oak

Treesearch

Tedmund J. Swiecki; Elizabeth Bernhardt; Christiana Drake; Laurence R. Costello

2006-01-01

In autumn 2002, we conducted a retrospective study on coast live oak (Quercus agrifolia) failures in Marin County, California, woodlands affected by Phytophthora ramorum canker (sudden oak death). The objectives of this case-control study were to quantify levels of bole, large branch, and root failure in these woodlands and...

Soil-site relationships of the upland oaks

Treesearch

Willard H. Carmean

1971-01-01

Site quality for upland oaks can be estimated directly by using site-index curves, or indirect estimations can be made by using soil-site prediction methods. Presently available harmonized site-index curves may not be suitable for all upland oak species, or may not be suitable throughout their range. New stem-analysis data show that different species of oak have...

Gypsy moth impacts on oak acorn production

Treesearch

Kurt W. Gottschalk

1991-01-01

Gypsy moth outbreaks can have drastic effects on many f a s t resources and uses. Because gypsy moth prefers oak foliage, oak stands are the most susceptible to defoliation and resultant damage. The value of oak mast for many wildlife species is high. The high carbohydrate content of acorns provides the energy necessary for winter survival. Loss of mast crops due to...

Combat Oak Shortage Problems Using Fortified Stringers

Treesearch

Philip A. Araman

1993-01-01

Oak pallet material supplies from sawmills have been and may continue to be difficult to secure in quantities by the pallet industry. Other oak using markets such as the furniture, cabinet, tie and flooring markets need more oak and are paying much higher prices than pallet manufacturers and recyclers wish to or can pay. These other markets are also willing to take...

Development, succession, and stand dynamics of upland oak forests in the Wisconsin Driftless Area: Implications for oak regeneration and management

Treesearch

Megan L. Buchanan; Kurt F. Kipfmueller; Anthony W. D' Amato

2017-01-01

Throughout the deciduous forests of the eastern United States, oak (Quercus) regeneration has declined in stands historically dominated by oak species. In the Wisconsin Driftless Area, the level of decline in oak regeneration is variable and influenced by stand structural development, historical disturbance regime, abiotic site characteristics, and...

Identification, amounts, and kinetics of extraction of C-glucosidic ellagitannins during wine aging in oak barrels or in stainless steel tanks with oak chips.

PubMed

Jourdes, Michaël; Michel, Julien; Saucier, Cédric; Quideau, Stéphane; Teissedre, Pierre-Louis

2011-09-01

The C-glucosidic ellagitannins are found in wine as a result of its aging in oak barrels or in stainless steel tanks with oak chips. Once dissolved in this slightly acidic solution, the C-glucosidic ellagitannins vescalagin can react with nucleophilic entities present in red wine, such as ethanol, catechin, and epicatechin, to generate condensed hybrid products such as the β-1-O-ethylvescalagin and the flavano-ellagitannins (acutissimin A/B and epiacutissimin A/B), respectively. During this study, we first monitored the extraction kinetic and the evolution of the eight major oak-derived C-glucosidic ellagitannins in red wines aged in oak barrels or in stainless steel tank with oak chips. Their extraction rates appeared to be faster during red wine aging in stainless steel tanks with oak chips. However, their overall concentrations in wines were found higher in the wine aged in barrels. The formation rates of the vescalagin-coupled derivatives were also estimated for the first time under both red wine aging conditions (i.e., oak barrels or stainless steel tanks with oak chips). As observed for the oak-native C-glucosidic ellagitannins, the concentrations of these vescalagin derivatives were higher in the red wine aged in oak barrels than in stainless steel tanks with oak chips. Despite these differences, their relative composition was similar under both red wine aging conditions. Finally, the impact of the oak chips size and toasting level on the C-glucosidic ellagitannins concentration in wine was also investigated.

Population genetics and biological control of goldspotted oak borer, an invasive pest of California oaks

Treesearch

Vanessa Lopez; Paul F. Rugman-Jones; Tom W. Coleman; Richard Stouthamer; Mark Hoddle

2015-01-01

California’s oak woodlands are threatened by the recent introduction of goldspotted oak borer (Agrilus auroguttatus). This invasive wood-borer is indigenous to mountain ranges in southern Arizona where its low population densities may be due to the presence of co-evolved, host-specific natural enemies. Reuniting A. auroguttatus...

Amplification of North American Red Oak Microsatellite Markers in European White Oaks and Chinese Chestnut

Treesearch

P. R. Aldrich; M. Jagtap; C. H. Michler; J. Romero-Severson

2003-01-01

We examined the cross-species amplification success of thirty microsatellite markers developed from North American northern red oak (Quercus rubra) in other members of the family Fagaceae. Sixteen of these markers are newly developed and we report primer sequences and amplification conditions here. Twelve of the thirty (40.0%) red oak markers...

Changes in glutathione redox cycle during diapause determination and termination in the bivoltine silkworm, Bombyx mori.

PubMed

Zhao, Lin-Chuan; Hou, Yi-Sheng; Sima, Yang-Hu

2014-02-01

To explore whether glutathione regulates diapause determination and termination in the bivoltine silkworm Bombyx mori, we monitored the changes in glutathione redox cycle in the ovary of both diapause- and nondiapause-egg producers, as well as those in diapause eggs incubated at different temperatures. The activity of thioredoxin reductase (TrxR) was detected in ovaries but not in eggs, while neither ovaries nor eggs showed activity of glutathione peroxidase. A lower reduced glutathione/oxidized glutathione (GSH/GSSG) ratio was observed in the ovary of diapause-egg producers, due to weaker reduction of oxidized glutathione (GSSG) to the reduced glutathione (GSH) catalyzed by glutathione reductase (GR) and TrxR. This indicates an oxidative shift in the glutathione redox cycle during diapause determination. Compared with the 25°C-treated diapause eggs, the 5°C-treated diapause eggs showed lower GSH/GSSG ratio, a result of stronger oxidation of GSH catalyzed by thioredoxin peroxidase and weaker reduction of GSSG catalyzed by GR. Our study demonstrated the important regulatory role of glutathione in diapause determination and termination of the bivoltine silkworm. © 2013 Institute of Zoology, Chinese Academy of Sciences.

Update on oak seed quality research: Hardwood recalcitrant seeds

Treesearch

Kristina F. Connor

2004-01-01

In 2 experiments, acorns of cherrybark oak (Quercus pagoda Raf.) and water oak (Q. nigra L.) were stored at 2 temperatures and 2 moisture contents for 3 years, and acorns of white oak (Q. alba L.) and cherrybark oak were desiccated over a span of up to 11 days and examined for physiological and biochemical...

Surface radiological investigations at White Wing Scrap Yard, Oak Ridge Reservation, Oak Ridge, Tennessee

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

Williams, J.K.; Rodriguez, R.E.; Uziel, M.S.

1991-09-01

A surface radiological scoping survey of accessible areas at the White Wing Scrap Yard (Waste Area Grouping 11 (WAG 11)) was conducted intermittently from December 1989 through July 1991 by members of the Measurement Applications and Development Group, Health and Safety Research Division, Oak Ridge National Laboratory (ORNL) at the request of Environmental Restoration Program personnel at ORNL. The White Wing Scrap Yard is an estimated 30-acre, predominately wooded area located on the western edge of East Fork Ridge in the McNew Hollow area on the US Department of Energy's Oak Ridge Reservation. The scrap yard was formerly used formore » aboveground storage of contaminated material (e.g., steel tanks, metal, glass, concrete, and miscellaneous industrial trash) from the Oak Ridge K-25 Site, Oak Ridge Y-12 Plant, and ORNL. The purposes of this cursory investigation were (1) to provide an updated contamination status of the site by locating and interpreting the presence, nature, and extent of surface radiological contamination and (2) to provide a basis for the formulation of interim corrective action to limit human exposures to radioactivity and minimize the potential for contaminant dispersion. 13 refs., 17 figs., 5 tabs.« less

Refining the oak-fire hypothesis for management of oak-dominated forests of the eastern United States

Treesearch

Mary A. Arthur; Heather D. Alexander; Daniel C. Dey; Callie J. Schweitzer; David L. Loftis

2012-01-01

Prescribed fires are increasingly implemented throughout eastern deciduous forests to accomplish various management objectives, including maintenance of oak-dominated (Quercus spp.) forests. Despite a regional research-based understanding of prehistoric and historic fire regimes, a parallel understanding of contemporary fire use to preserve oak...

Middle region of FancM interacts with Mhf and Rmi1 in silkworms, a species lacking the Fanconi anaemia (FA) core complex.

PubMed

Sugahara, R; Mon, H; Lee, J M; Kusakabe, T

2014-04-01

The Fanconi anaemia (FA) pathway is responsible for interstrand crosslink (ICL) repair. Among the FA core complex components, FANCM is believed to act as a damage sensor for the ICL-blocked replication fork and also as a molecular platform for FA core complex assembly and interaction with Bloom's syndrome (BS) complex that is thought to play an important role in the processing of DNA structures such as stalled replication forks. In the present study, we found that in silkworms, Bombyx mori, a species lacking the major FA core complex components (FANCA, B, C, E, F, and G), FancM is required for FancD2 monoubiquitination and cell proliferation in the presence of mitomycin C (MMC). Silkworm FancM (BmFancM) was phosphorylated in the middle regions, and the modification was associated with its subcellular localization. In addition, BmFancM interacted with Mhf1, a histone-fold protein, and Rmi1, a subunit of the BS complex, in the different regions. The interaction region containing at least these two protein-binding domains played an essential role in FancM-dependent resistance to MMC. Our results suggest that BmFancM also acts as a platform for recruitment of both the FA protein and the BS protein, although the silkworm genome seems to lose FAAP24, a FancM-binding partner protein in mammals. © 2013 The Royal Entomological Society.

Seeding and planting upland oaks

Treesearch

1989-01-01

Oaks can be planted or seeded in uplands to: (1) afforest old fields, strip-mined areas, or other areas devoid of trees, and (2) supplement natural reproduction within existing forests. Planting is usually more successful than direct seeding. But even under good conditions survival and growth of planted oak has been considerably poorer than with conifers and other...

Regenerating oaks in Missouri's bottomlands

Treesearch

Dan Dey; John Kabrick

2004-01-01

Bottomland oaks are valuable timber species that are also important for wildlife, but regenerating them is about as easy as training blackbirds to plant acorns. Missouri once had an estimated 5 million acres of wetlands, much of which were bottomland forests that included some oak. Today, less than 15 percent of those historical wetlands remain in the state. Many...

The mighty oak faces challenges in the Pacific West

Treesearch

Gail Wells

2010-01-01

In popular imagination, the oak tree stands for strength, endurance, and longevity. But in the coastal lowlands and central valleys of British Columbia, Washington, Oregon, and California, oaks face a battery of natural and human-induced threats. Sudden oak death, caused by a virulent pathogen identified in 2000, has killed millions of tanoaks, California black oaks,...

Midstory removal methods tested for timely release of newly established oak seedlings under oak shelterwoods

Treesearch

Ronald A. Rathfon

2011-01-01

The oak shelterwood method calls for the removal of shade-tolerant, undesirable midstory species to create adequate diffuse light conditions at the forest floor for oak seedling establishment, preferably timed to coincide with a large acorn crop. Injection (INJ) with an herbicide, chainsaw felling and girdling with herbicide application (SAW), and a low-volume basal...

Effects of transient high temperature treatment on the intestinal flora of the silkworm Bombyx mori.

PubMed

Sun, Zhenli; Kumar, Dhiraj; Cao, Guangli; Zhu, Liyuan; Liu, Bo; Zhu, Min; Liang, Zi; Kuang, Sulan; Chen, Fei; Feng, Yongjie; Hu, Xiaolong; Xue, Renyu; Gong, Chengliang

2017-06-13

The silkworm Bombyx mori is a poikilotherm and is therefore sensitive to various climatic conditions. The influence of temperature on the intestinal flora and the relationship between the intestinal flora and gene expression in the silkworm remain unknown. In the present study, changes of the intestinal flora at 48, 96 and 144 h following transient high temperature treatment (THTT) of 37 °C for 8 h were investigated. According to principal component analysis, the abundances of Enterococcus and Staphylococcus showed a negative correlation with other dominant genera. After THTT, the gene expression levels of spatzle-1 and dicer-2 were increased and decreased, respectively, which suggested that the Toll and RNAi pathways were activated and suppressed, respectively. The species-gene expression matrix confirmed that the spatzle-1 and dicer-2 gene expression levels were negatively and positively correlated, respectively, with the abundance of Enterococcus and Staphylococcus in the control. The abundance of Variovorax post-THTT was positively correlated with the spatzle-1 gene expression level, whereas the community richness of Enterococcus was negatively correlated with the spatzle-1 gene expression level and positively correlated with the dicer-2. The results of the present investigation provide new evidence for understanding the relationships among THTT, intestinal flora and host gene expression.

The effect of hemoperfusion on patients with toxic encephalopathy induced by silkworm chrysalis ingestion.

PubMed

Hu, Haixia; Wang, Xu; Lv, Jiaqi; Sun, Jing; Xing, Jihong; Liu, Xiaoliang

2016-08-01

This study aims to determine therapeutic effect of hemoperfusion on patients with acute toxic encephalopathy induced by silkworm chrysalis ingestion. Three patients who developed toxic encephalopathy after chrysalis ingestion were analysed. Two patients lost their consciousness, while two patients had typical extrapyramidal tremor symptoms. Further neurological examination revealed various degrees of muscle strength impairment in these patients. All of them received treatments of omeprazole (40 mg/day), furosemide (one dose of 20 mg), vitamin C (2.0 g/day), calcium gluconate (2.0 g/day) and rehydration with glucose and sodium chloride (1500 ml/day). In addition, they received hemoperfusion treatment for 1.5 h. All patients recovered well after hemoperfusion. Two patients with loss of consciousness significantly recovered at 45 min and 65 min after hemoperfusion, respectively. All tremor symptoms were completely resolved in these patients at 30 min, 50 min, and 70 min following treatment, respectively. After the hemoperfusion treatment, encephalopathy symptoms of two patients had completely disappeared. All patients were followed up for one month and did not report any abnormalities. Our study indicates that hemoperfusion could be a useful and efficient treatment strategy for patients with acute encephalopathy after silkworm chrysalis ingestion. Larger clinical trials with longer follow-up are warranted to confirm the clinical benefit of hemoperfusion. © The Author(s) 2015.

Flush Development Dynamics in First-Year Nursery-Grown Seedlings of Eight Oak Species

Treesearch

Shi-Jean S. Sung; Paul P. Kormanik; Stanley J. Zarnoch

2004-01-01

Two experiments were conducted to follow flush development dynamics exhibited by various oak species. In experiment I, southern red oak acorns were sown in mid-March 2001 at Whitehall Nursery (Athens, GA). In experiment II, acorns of black oak, cherrybark oak, Nuttall oak, Shumard oak, southern red oak, swamp chestnut oak, white oak, and willow oak were sown in...

Application of Propiconazole and Pseudomonas Cichorii for Control of Oak Wilt in Texas Live Oaks

Treesearch

A. Dan Wilson; D.G. Lester

1995-01-01

The efficacy of two formulations of propiconazole, Banner and Tilt, and biocontrol agent (Pseudomonas cichorii) for Control of oak wilt was tested in a natural mature stand of live oaks at a location near Yoakum, Texas with a predominantly sandy soil type. The field plots, established 15 March 85, consisted of five randomly selected plot locations...

Effect of ground skidding on oak advance regeneration

Treesearch

Jeffrey W. Stringer

2006-01-01

Vigorous advance regeneration is required to naturally regenerate oaks. However, a reduction in the number of advance regeneration stems from harvesting activities could be an important factor in determining successful oak regeneration. This study assessed the harvest survivability of advance regeneration of oak (Quercus spp.) and co-occurring...

Butt log quality of trees in Pennsylvania oak stands

Treesearch

Martin E. Dale; Robert L. Brisbin; Robert L. Brisbin

1985-01-01

Describes the distribution of sawtimber trees by diameter at breast height (d.b.h.) and grade for eight hardwood species in upland oak stands of Pennsylvania. The proportion of trees by d.b.h. and grade revealed differences between species. The quality of northern red oak, white oak, and yellow-poplar appeared inherently better than that of red maple, chestnut oak, and...

Releasing red oak reproduction using a growing season application of Oust

Treesearch

Jamie L. Schuler; John Stephens

2010-01-01

In most cases, newly harvested upland oak stands contain sufficient numbers of red oak stems to form a fully stocked oak stand in the future. Unfortunately, many stands will not reach full stocking of oak due to intense competition from other non-oak reproduction. There are few feasible options to release established oak reproduction from other broadleaf woody or non-...

The oak woodland bird conservation plan: a strategy for protecting and managing oak woodland habitats and associated birds in California

Treesearch

Steve Zack; Mary K. Chase; Geoffrey R. Geupel

2002-01-01

Over 330 species of birds, mammals, reptiles, and amphibians depend on oak woodlands in California at some stage in their life cycle. California oak woodlands may rank among the top three habitat types in North America for bird richness. Oak woodlands are able to sustain such abundant wildlife primarily because they produce acorns, a high quality and frequently copious...

Performance of nutrient-loaded red oak and white oak seedlings on mine lands in southern Indiana

Treesearch

K. Francis Salifu; Douglass F. Jacobs; Zonda K. D. Birge

2008-01-01

Exponential nutrient loading was used to build nutrient reserves in northern red oak (Quercus rubra) and white oak (Q. alba) seedlings during standard bareroot nursery culture at the Vallonia State Nursery, Indiana. Nursery grown seedlings were outplanted the following year onto a mine reclamation site in southern Indiana to...

Oak Regeneration by Direct Seeding

Treesearch

Robert L. Johnson; Roger M. Krinard

1985-01-01

Direct sowing of oak acorns has not always met with success. This paper summarizes recent research regarding direct sowing of oaks in research plots and commercial trials. Present findings indicate that seedlings can be established from properly stored acorns sown any month of the year by hand or machine . They should be sown at a two-inch depth , although they can be...

Quantification of silkworm coactivator of MBF1 mRNA by SYBR Green I real-time RT-PCR reveals tissue- and stage-specific transcription levels.

PubMed

Li, Guang-li; Roy, Bhaskar; Li, Xing-hua; Yue, Wan-fu; Wu, Xiao-feng; Liu, Jian-mei; Zhang, Chuan-xi; Miao, Yun-gen

2009-05-01

Transcriptional coactivators play a crucial role in gene transcription and expression. Multiprotein bridging factor 1 (MBF1) is a transcriptional coactivator necessary for transcriptional activation caused by DNA-binding activators, such as FTZ-F1 and GCN4. Until now, very few studies have been reported in the silkworm. We selected the Bombyx mori because it is a model insect and acts as an economic animal for silk industry. In this study, we conducted the quantitative analysis of MBF1 mRNA in silkworm B. mori L. with actin (A3) as internal standard by means of SYBR Green I real-time RT-PCR method. The total RNA was extracted from the silk gland, epidermis, fat body, and midguts of the fifth instar B. mori larvae. The mRNA was reverse transcripted, and the cDNA fragments of MBF1 mRNA and actin gene were amplified by RT-PCR using specific primers. MBF1 mRNA expression in different tissues of silkworm B. mori L. was quantified using standardized SYBR Green I RT-PCR. The results suggested MBF1 gene was expressed in all investigated organs but highly expressed in the silk gland, showing its relation to biosynthesis of silk proteins.

Mössbauer studies of subfossil oak

NASA Astrophysics Data System (ADS)

van Bürck, Uwe; Wagner, Friedrich E.; Lerf, Anton

2012-03-01

Subfossil oak wood found in a dried-up bog in Bavaria, Germany, was studied by Mössbauer spectroscopy. The bog oaks contain substantial amounts of iron taken up from the bog waters and presumably forming complexes with the tanning agents in the oak wood. The iron is mainly Fe3 + and much of this exhibits an uncommonly large quadrupole splitting of up to 1.6 mm/s that can tentatively be explained by the formation of oxo-bridged iron dimers. Only rarely, mainly in the dense wood of the roots of bog oaks, was divalent iron found. When the wood was ground to a powder the divalent iron oxidized to Fe3 + within hours. This suggests that iron is taken up from the bog water as Fe2 + and oxidizes only when the wood emerges from the water and comes into contact with air.

Bone regeneration by polyhedral microcrystals from silkworm virus

PubMed Central

Matsumoto, Goichi; Ueda, Takayo; Shimoyama, Junko; Ijiri, Hiroshi; Omi, Yasushi; Yube, Hisato; Sugita, Yoshihiko; Kubo, Katsutoshi; Maeda, Hatsuhiko; Kinoshita, Yukihiko; Arias, Duverney Gaviria; Shimabukuro, Junji; Kotani, Eiji; Kawamata, Shin; Mori, Hajime

2012-01-01

Bombyx mori cypovirus is a major pathogen which causes significant losses in silkworm cocoon harvests because the virus particles are embedded in micrometer-sized protein crystals called polyhedra and can remain infectious in harsh environmental conditions for years. But the remarkable stability of polyhedra can be applied on slow-release carriers of cytokines for tissue engineering. Here we show the complete healing in critical-sized bone defects by bone morphogenetic protein-2 (BMP-2) encapsulated polyhedra. Although absorbable collagen sponge (ACS) safely and effectively delivers recombinant human BMP-2 (rhBMP-2) into healing tissue, the current therapeutic regimens release rhBMP-2 at an initially high rate after which the rate declines rapidly. ACS impregnated with BMP-2 polyhedra had enough osteogenic activity to promote complete healing in critical-sized bone defects, but ACS with a high dose of rhBMP-2 showed incomplete bone healing, indicating that polyhedral microcrystals containing BMP-2 promise to advance the state of the art of bone healing. PMID:23226833

Factors limiting northern red oak reproduction in Pennsylvania

Treesearch

Russell S. Walters; L. R. Auchmoody

1993-01-01

When harvested, upland oak forests of northwestern Pennsylvania generally regenerate to new forests dominated by non-oak species. In 1988, the Northeastern Forest Experiment Station began to identify and learn to manipulate factors that limit the establishment and development of northern red oak (Quercus rubra L.) seedlings in second-generation...

Zygotic amplification of secondary piRNAs during silkworm embryogenesis

PubMed Central

Kawaoka, Shinpei; Arai, Yuji; Kadota, Koji; Suzuki, Yutaka; Hara, Kahori; Sugano, Sumio; Shimizu, Kentaro; Tomari, Yukihide; Shimada, Toru; Katsuma, Susumu

2011-01-01

PIWI-interacting RNAs (piRNAs) are 23–30-nucleotide-long small RNAs that act as sequence-specific silencers of transposable elements in animal gonads. In flies, genetics and deep sequencing data have led to a hypothesis for piRNA biogenesis called the ping-pong cycle, where antisense primary piRNAs initiate an amplification loop to generate sense secondary piRNAs. However, to date, the process of the ping-pong cycle has never been monitored at work. Here, by large-scale profiling of piRNAs from silkworm ovary and embryos of different developmental stages, we demonstrate that maternally inherited antisense-biased piRNAs trigger acute amplification of secondary sense piRNA production in zygotes, at a time coinciding with zygotic transcription of sense transposon mRNAs. These results provide on-site evidence for the ping-pong cycle. PMID:21628432

77 FR 23506 - Notice of Inventory Completion: The Region of Three Oaks Museum, Three Oaks, MI

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-19

.... SUMMARY: The Region of Three Oaks Museum has completed an inventory of human remains, in consultation with... between the human remains and a present-day Indian tribe. Representatives of any Indian tribe that believes itself to be culturally affiliated with the human remains may contact The Region of Three Oaks...

Bird communities of gambel oak: a descriptive analysis

Treesearch

Andreas Leidolf; Michael L. Wolfe; Rosemary L. Pendleton

2000-01-01

Gambel oak (Quercus gambelii Nutt.) covers 3.75 million hectares (9.3 million acres) of the western United States. This report synthesizes current knowledge on the composition, structure, and habitat relationships of gambel oak avian communities. It lists life history attributes of 183 bird species documented from gambel oak habitats of the western...

A Dendrochronological Analysis of Red Oak Borer Abundance

Treesearch

Rose-Marie Muzika; Richard P. Guyette

2004-01-01

Unprecedented outbreaks of red oak borer (Enaphalodes rufulus Haldemann) have occurred in the lower Midwestern United States. Although generally not a mortality agent, red oak borer appears to contribute to general oak decline and mortality. The objective of this project was to explore dendrochronology as a means of determining the role of tree age,...

Impact of a spring defoliator on common oak

Treesearch

Victor V. Rubtsov; Irina A. Utkina

1991-01-01

We have investigated the population dynamics of some common phyllophagous insects in oak stands of the forest-steppe zone and their impact on common oak (Quercus robur L). Considerable attention has also been paid to mathematical modeling of the studied processes. All field data represent samples taken from the Tellerman oak grove in the Voronezh...

Managing California black oak for tribal ecocultural restoration

Treesearch

Jonathan W. Long; Ron W. Goode; Raymond J. Gutteriez; Jessica J. Lackey; M. Kat Anderson

2017-01-01

Many tribes in California and Oregon value California black oak (Quercus kelloggii) as a traditional source of food and other values. Over centuries or millennia, Native Americans learned that they could enhance production of desired resources by regularly igniting low-intensity surface fires in stands of black oak. Although black oak is likely to...

Thirty-year assessment of released, overtopped white oaks

Treesearch

C. Miller; S. Grayson; A. Houser; W. Clatterbuck; K. Kuers

2011-01-01

White oak (Quercus alba L.) is a slow-growing species that is often overtopped in the mixed upland hardwood forests of the Cumberland Plateau. Forest managers have concerns about the potential economic value of releasing overtopped white oaks to become valuable crop trees. This study follows the growth and development of 104 overtopped white oaks...

Influence of Fire on Oak Seedlings and Saplings in Southern Oak Woodland on the Santa Rosa Plateau Preserve, Riverside County, California

Treesearch

Earl W. Lathrop; Chris D. Osborne

1991-01-01

One wildfire and two prescription burns were monitored at 15 oak seedling/sapling regeneration sites and at four non-burned comparison sites to study the effect of fire on seedlings and saplings of Quercus engelmannii (Engelmann oak) and Q. agrifolia (coast live oak). The number of initial topkilled seedlings and saplings, initial...

Silviculture to restore oak woodlands

Treesearch

Daniel C. Dey; Callie J. Schweitzer; John M. Kabrick

2016-01-01

Variability in historic fire regimes in eastern North America resulted in an array of oak savannas, woodlands and forests that were dominant vegetation types throughout the region. In the past century, once abundant woodlands have become scarce due to conversion to agriculture, or development of forest structure in the absence of fire. Restoration of oak woodlands is a...

MicroRNA-281 regulates the expression of ecdysone receptor (EcR) isoform B in the silkworm, Bombyx mori

USDA-ARS?s Scientific Manuscript database

Hundreds of Bombyx mori miRNAs had been identified in recent years, but their function in vivo remains poorly understood. The silkworm EcR gene (BmEcR) has three transcriptional isoforms, A, B1 and B2. Isoform sequences are different in the 3’UTR region of the gene, which is the case only in insects...

Reconstructing the competitive dynamics of mixed-oak neighborhoods

Treesearch

Eric K. Zenner; Daniel J. Heggenstaller; Patrick H. Brose; JeriLynn E. Peck; Kim C. Steiner

2012-01-01

The disparity between the potential for latent oak dominance within a stand and their region-wide decline in importance value raises questions about the competitiveness of oaks in early stand dynamics. We reconstructed tree height growth dynamics in mixed-species neighborhoods to determine if currently dominant oaks were ever shorter than their competitors and at what...

Challenges and successes in managing oak wilt in the United States

Treesearch

Jennifer Juzwik; David N. Appel; William L. MacDonald; Susan. Burks

2011-01-01

Oak wilt, caused by the fungus Ceratocystis fagacearum (Bretz) J. Hunt, is an important disease of oaks (Quercus spp.) in the eastern United States. It has been particularly destructive in the North Central states and Texas. Oak wilt is one of several significant oak diseases that threaten oak health worldwide. The significant...

Responses of oaks and tanoaks to the sudden oak death pathogen after 8 y of monitoring in two coastal California forests

Treesearch

Brice A. McPherson; Sylvia R. Mori; David L. Wood; Maggi Kelly; Andrew J. Storer; Pavel Svihra; Richard B. Standiford

2010-01-01

Sudden oak death, caused by Phytophthora ramorum, is widely established in mesic forests of coastal central and northern California. In 2000, we placed 18 plots in two Marin County sites to monitor disease progression in coast live oaks (Quercus agrifolia), California black oaks (Q. kelloggii), and tanoaks (Lithocarpus densiflorus), the species that are most...

Phytophthora ramorum canker (Sudden Oak Death) disease risk and progress in coast live oak, 2000-2012

Treesearch

Tedmund J. Swiecki; Elizabeth Bernhardt

2015-01-01

From 2000 through 2012, we collected annual observations on disease symptoms and stand conditions in 128 coast live oak plots in forests affected by sudden oak death (SOD), caused by the introduced pathogen Phytophthora ramorum. Elevated rainfall in one or both of the previous wet seasons was associated with pulses of new infections. However,...

Using Forest Service forest inventory and analysis data to estimate regional oak decline and oak mortality

Treesearch

Kathryn W. Kromroy; Jennifer Juzwik; Paul Castillo; Mark H. Hansen

2008-01-01

Damage and mortality data are collected as part of the US Forest Service, Forest Inventory and Analysis (FIA) ongoing assessments of the nation's timberlands. The usefulness and value of FIA tree data in assessing historical levels of oak decline and oak mortality were investigated for seven Midwestern states. The data were collected during two periodic...

Energy content in dried leaf litter of some oaks and mixed mesophytic species that replace oaks

Treesearch

Aaron D. Stottlemeyer; G. Geoff Wang; Patrick H. Brose; Thomas A. Waldrop

2010-01-01

Mixed-mesophytic hardwood tree species are replacing upland oaks in vast areas of the Eastern United States deciduous forest. Some researchers have suggested that the leaf litter of mixed-mesophytic, oak replacement species renders forests less flammable where forest managers wish to restore a natural fire regime. We performed chemical analyses on dried leaf litter...

Occupational poison ivy and oak dermatitis.

PubMed

Epstein, W L

1994-07-01

Among the growing and diverse groups of outdoor and environmental workers, poison ivy and poison oak continue to be the major cause of occupational contact dermatitis. This article reviews the practical and theoretic means to prevent poison ivy and poison oak dermatitis in workers occupationally exposed to these weeds.

Annotation and expression of carboxylesterases in the silkworm, Bombyx mori.

PubMed

Yu, Quan-You; Lu, Cheng; Li, Wen-Le; Xiang, Zhong-Huai; Zhang, Ze

2009-11-24

Carboxylesterase is a multifunctional superfamily and ubiquitous in all living organisms, including animals, plants, insects, and microbes. It plays important roles in xenobiotic detoxification, and pheromone degradation, neurogenesis and regulating development. Previous studies mainly used Dipteran Drosophila and mosquitoes as model organisms to investigate the roles of the insect COEs in insecticide resistance. However, genome-wide characterization of COEs in phytophagous insects and comparative analysis remain to be performed. Based on the newly assembled genome sequence, 76 putative COEs were identified in Bombyx mori. Relative to other Dipteran and Hymenopteran insects, alpha-esterases were significantly expanded in the silkworm. Genomics analysis suggested that BmCOEs showed chromosome preferable distribution and 55% of which were tandem arranged. Sixty-one BmCOEs were transcribed based on cDNA/ESTs and microarray data. Generally, most of the COEs showed tissue specific expressions and expression level between male and female did not display obvious differences. Three main patterns could be classified, i.e. midgut-, head and integument-, and silk gland-specific expressions. Midgut is the first barrier of xenobiotics peroral toxicity, in which COEs may be involved in eliminating secondary metabolites of mulberry leaves and contaminants of insecticides in diet. For head and integument-class, most of the members were homologous to odorant-degrading enzyme (ODE) and antennal esterase. RT-PCR verified that the ODE-like esterases were also highly expressed in larvae antenna and maxilla, and thus they may play important roles in degradation of plant volatiles or other xenobiotics. B. mori has the largest number of insect COE genes characterized to date. Comparative genomic analysis suggested that the gene expansion mainly occurred in silkworm alpha-esterases. Expression evidence indicated that the expanded genes were specifically expressed in midgut, integument and

Annotation and expression of carboxylesterases in the silkworm, Bombyx mori

PubMed Central

2009-01-01

Background Carboxylesterase is a multifunctional superfamily and ubiquitous in all living organisms, including animals, plants, insects, and microbes. It plays important roles in xenobiotic detoxification, and pheromone degradation, neurogenesis and regulating development. Previous studies mainly used Dipteran Drosophila and mosquitoes as model organisms to investigate the roles of the insect COEs in insecticide resistance. However, genome-wide characterization of COEs in phytophagous insects and comparative analysis remain to be performed. Results Based on the newly assembled genome sequence, 76 putative COEs were identified in Bombyx mori. Relative to other Dipteran and Hymenopteran insects, alpha-esterases were significantly expanded in the silkworm. Genomics analysis suggested that BmCOEs showed chromosome preferable distribution and 55% of which were tandem arranged. Sixty-one BmCOEs were transcribed based on cDNA/ESTs and microarray data. Generally, most of the COEs showed tissue specific expressions and expression level between male and female did not display obvious differences. Three main patterns could be classified, i.e. midgut-, head and integument-, and silk gland-specific expressions. Midgut is the first barrier of xenobiotics peroral toxicity, in which COEs may be involved in eliminating secondary metabolites of mulberry leaves and contaminants of insecticides in diet. For head and integument-class, most of the members were homologous to odorant-degrading enzyme (ODE) and antennal esterase. RT-PCR verified that the ODE-like esterases were also highly expressed in larvae antenna and maxilla, and thus they may play important roles in degradation of plant volatiles or other xenobiotics. Conclusion B. mori has the largest number of insect COE genes characterized to date. Comparative genomic analysis suggested that the gene expansion mainly occurred in silkworm alpha-esterases. Expression evidence indicated that the expanded genes were specifically

Foliar nutrient concentrations of oak, hickory, and red maple

Treesearch

Amy J. Scherzer; Robert P. Long; Joanne Rebbeck

2003-01-01

Early autumn foliar nutrient concentrations of overstory oak (white oak [Quercus alba L.] or chestnut oak [Q. prinus L.]) understory hickory (mockernut hickory [Carya tomentosa (Poir.) Nutt.] or pignut hickory [C. glabra (Mill.) Sweet]), and both overstory and understory red maple (...

Effects of shading on growth and development of northern red oak, black oak, black cherry, and red maple seedlings. II. biomass partitioning and prediction

Treesearch

Kurt W. Gottschalk

1987-01-01

Northern red oak, black oak, black cherry, and red maple seedlings were grown under light treatments ranging from 8 to 94% of full sunlight for 2 years. Growth was least at the lowest light level and total dry weight increased with increasing light. Total dry-weight rankings (largest to smallest) at all light levels were black cherry, northern red oak, black oak, and...

Tests of wildlife habitat models to evaluate oak-mast production

USGS Publications Warehouse

Schroeder, R.L.; Vangilder, L.D.

1997-01-01

We measured oak-mast production and forest structure and composition in the Ozark Mountains of Missouri and tested the accuracy of oak-mast prediction variables from 5 Habitat Suitability Index (HSI) species models. Acorn production was positively associated with several measures of abundance and canopy cover of oak trees, and with an index of mast production for all 5 HSI models. We developed 2 modified oak-mast models, based on inputs related to either oak tree density or oak canopy cover and diversity of oak tree species. The revised models accounted for 22-32% of the variance associated with acorn abundance. Future tests of HSI models should consider: (1) the concept of upper limits imposed by habitat and the effects of nonhabitat factors; (2) the benefits of a top-down approach to model development; and (3) testing models across broad geographic regions.

Vegetation and small vertebrates of oak woodlands at low and high risk for sudden oak death in San Luis Obispo County, California.

Treesearch

Douglas J. Tempel; William D. Tietje; Donald E. Winslow

2006-01-01

San Luis Obispo County contains oak woodlands at varying levels of risk of sudden oak death (SOD), caused by a fungal pathogen (Phytophthora ramorum) that in the past decade has killed thousands of oak (Quercus spp.) and tanoak (Lithocarpus densiflorus) trees in California. SOD was most recently detected 16...

Effects of hypervitaminosis of vitamin B3 on silkworm biology.

PubMed

Etebari, Kayvan; Matindoost, Leila

2004-12-01

A high-dose of vitamin B(3) in silkworm diet interrupts larval feeding and normal growth. High mortality of larvae occurs during molting and they cannot complete this process normally. Also the larvae exhibit nicotinamide hypervitaminosis symptoms such as immobility, dyspepsia, darkening of the skin, inability to excrete normally, exerting brownish fluid from anus and swelling of rectal muscles. Maximum larval weights in 1, 2 and 3 g/l treatments were 2.9, 1.6 and 1.2 g respectively, while maximum larval weight in the control was 5.6 g. Larval stage compared to control had increased 18, 26 and 31 days respectively. The concentration increase of uric acid in haemolymph demonstrates the hyperuricemia, while other measured biochemical compounds show significant decrease; sodium and potassium did not change significantly.

Adequate Oak Regeneration - A Problem Without a Solution?

Treesearch

Robert L. Johnson

1979-01-01

The current supply of oak (Quercus spp.) in eastern forests appears abundant. Knight and Hilmon (1978) report a 42 percent increase in total oak sawtimber between 1952 and 1977. In 1977, board-foot growth (Int. 1/4") was slightly less and cubic-foot growth slightly more than twice the amount of annual removals. But the long term outlook for oak...

Ten-year results of using oak Cleanings to maintain oak species dominance on the Allegheny National Forest

Treesearch

Kurt W. Gottschalk; Gary W. Miller; Robert White; Andrea Hille; Thomas M. Schuler

2014-01-01

The Allegheny National Forest (ANF) in northwestern Pennsylvania implemented precommercial thinning in young stands to maintain oak (Quercus spp.) stems in a competitive position. This administrative study was developed to test ANF standards for precommercial thinning for success in maintaining oak composition. An additional objective was to examine...

Cloning and analysis of DnaJ family members in the silkworm, Bombyx mori.

PubMed

Li, Yinü; Bu, Cuiyu; Li, Tiantian; Wang, Shibao; Jiang, Feng; Yi, Yongzhu; Yang, Huipeng; Zhang, Zhifang

2016-01-15

Heat shock proteins (Hsps) are involved in a variety of critical biological functions, including protein folding, degradation, and translocation and macromolecule assembly, act as molecular chaperones during periods of stress by binding to other proteins. Using expressed sequence tag (EST) and silkworm (Bombyx mori) transcriptome databases, we identified 27 cDNA sequences encoding the conserved J domain, which is found in DnaJ-type Hsps. Of the 27 J domain-containing sequences, 25 were complete cDNA sequences. We divided them into three types according to the number and presence of conserved domains. By analyzing the gene structures, intron numbers, and conserved domains and constructing a phylogenetic tree, we found that the DnaJ family had undergone convergent evolution, obtaining new domains to expand the diversity of its family members. The acquisition of the new DnaJ domains most likely occurred prior to the evolutionary divergence of prokaryotes and eukaryotes. The expression of DnaJ genes in the silkworm was generally higher in the fat body. The tissue distribution of DnaJ1 proteins was detected by western blotting, demonstrating that in the fifth-instar larvae, the DnaJ1 proteins were expressed at their highest levels in hemocytes, followed by the fat body and head. We also found that the DnaJ1 transcripts were likely differentially translated in different tissues. Using immunofluorescence cytochemistry, we revealed that in the blood cells, DnaJ1 was mainly localized in the cytoplasm. Copyright © 2015 Elsevier B.V. All rights reserved.

Regioselective formation of quercetin 5-O-glucoside from orally administered quercetin in the silkworm, Bombyx mori.

PubMed

Hirayama, Chikara; Ono, Hiroshi; Tamura, Yasumori; Konno, Kotaro; Nakamura, Masatoshi

2008-03-01

The cocoons of some races of the silkworm, Bombyx mori, have been shown to contain 5-O-glucosylated flavonoids, which do not occur naturally in the leaves of their host plant, mulberry (Morus alba). Thus, dietary flavonoids could be biotransformed in this insect. In this study, we found that after feeding silkworms a diet rich in the flavonol quercetin, quercetin 5-O-glucoside was the predominant metabolite in the midgut tissue, while quercetin 5,4'-di-O-glucoside was the major constituent in the hemolymph and silk glands. UDP-glucosyltransferase (UGT) in the midgut could transfer glucose to each of the hydroxyl groups of quercetin, with a preference for formation of 5-O-glucoside, while quercetin 5,4'-di-O-glucoside was predominantly produced if the enzyme extracts of either the fat body or silk glands were incubated with quercetin 5-O-glucoside and UDP-glucose. These results suggest that dietary quercetin was glucosylated at the 5-O position in the midgut as the first-pass metabolite of quercetin after oral absorption, then glucosylated at the 4'-O position in the fat body or silk glands. The 5-O-glucosylated flavonoids retained biological activity in the insect, since the total free radical scavenging capacity of several tissues increased after oral administration of quercetin.

Study on impact of parasite (Nosema species) on characters of tropical tasar silkworm Anthereae mylitta drury.

PubMed

Velide, Lakshmi; Bhagavanulu, M V K; Rao, A Purushotham

2013-01-01

Infection of the pebrine disease has been found to be highly virulent and harm the cocoon yield as well as characters of silkworm Anthereae mylitta. Therefore, an attempt was made to evaluate the impact of parasite Nosema species on the ecorace (Sukinda) of A. mylitta in respect of transovarial transmitted (T1), secondary infection (T2) and healthy silkworm (T3). In comparison to T3, the number of larval mortality was 16 and 11 in T1 and T2 respectively; whereas as number of pupal mortality was 6 and 5 in T1 and T2 respectivelyThe larval weight, number of moths emerged, number of eggs laid and percent hatchability were reduced in T1 and T2 in comparison to T3.The infected layings were high in T1 (51%) and T2 (42%) as against T3 (0%). Similarly, the infected moths were 34% in T1 and 15% in T2 as against 0 percent in T3. All the characteristics parameters of cocoon were reduced in T1 and T2 against T3. The study explains that there was no significant variation between T1 and T2 on different parameters of larva, pupa and cocoon characters.

Pretreatment Characteristics of Waste Oak Wood by Ammonia Percolation

NASA Astrophysics Data System (ADS)

Kim, Jun-Seok; Kim, Hyunjoon; Lee, Jin-Suk; Lee, Joon-Pyo; Park, Soon-Chul

A log of waste oak wood collected from a Korean mushroom farm has been tested for ammonia percolation pretreatment. The waste log has different physical characteristics from that of virgin oak wood. The density of the waste wood was 30% lower than that of virgin oak wood. However, there is little difference in the chemical compositions between the woods. Due to the difference in physical characteristics, the optimal pretreatment conditions were also quite different. While for waste oak the optimum temperature was determined to be 130°C, for virgin oak wood the optimum pretreatment was only achieved at 170°C. Presoaking for 12 h with ammonia solution before pretreatment was helpful to increase the delignification efficiency.

Effects of the goldspotted oak borer, Agrilus auroguttatus, on the health of coast live oak, Quercus agrifolia, in southern California before and after treatment with two systemic insecticides

Treesearch

Yigen Chen; Mary L. Flint; Tom W. Coleman; Joseph J. Doccola; Donald M. Grosman; David L. Wood; Steven J. Seybold

2015-01-01

The invasive goldspotted oak borer, Agrilus auroguttatus (Coleoptera: Buprestidae), is threatening the health and survival of oak trees in San Diego County, California (Flint and others 2013). The primary oak species colonized and killed in this area include coast live oak (Quercus agrifolia), California black oak (...

A field guide to insects and diseases of California oaks

Treesearch

Tedmund J. Swiecki; Elizabeth A. Bernhardt

2006-01-01

California has more than twenty-five native species, natural hybrids, and varieties of oaks (Quercus species). The form of these oaks ranges from large trees, up to about 25 m tall, to shrubs no taller than about 1.5 m. California's native oaks include representatives of three oak subgroups or subgenera (Table 1). Hybridization only occurs...

Harvest survivability of oak advanced regeneration

Treesearch

Jeff Stringer

2005-01-01

Natural regeneration of oak requires the occurrence of advance regeneration and/or stems capable of stump sprouting. These stems must be present before harvest and adequate numbers must survive harvest for oaks to successfully regenerate. Regeneration predictions are based on pre-harvest advance regeneration inventories. However, the use of these inventories does not...

Success of Underplanting Northern Red Oaks

Treesearch

Martin A. Spetich; Daniel C. Dey; Paul S. Johnson; David L. Graney

2004-01-01

We summarize results of the growth and survival of northern red oak (Quercus rubra L.) seedlings 11 years after planting in shelterwoods in the Boston Mountains of Arkansas. Shelterwood overstories were harvested 3 years after underplanting > 4,000 northern red oak seedlings. Woody vegetation that was competing with planted seedlings received two...

Sudden oak death in California: what is the potential?

Treesearch

Tara M. Barrett; Demetrios Gatziolis; Jeremy S. Fried; Karen L. Waddell

2006-01-01

Sudden oak death, a disease associated with the pathogen Phytophthora ramorum, has a large number of shrub and tree host species. Three of the tree species must susceptible to mortality from the disease, California black oak (Quercus kelloggii), coast live oak (Quercus agrifolia), and tanoak (...

Phytophthora ramorum infection in coast live oaks and Shreve's oaks treated with insecticide to prevent beetle colonization

Treesearch

Brice A. McPherson; David L. Wood; David M. Rizzo; Pavel Svihra; Steve Tjosvold; Andrew J. Storer; Richard B. Standiford

2006-01-01

As the name implies, sudden oak death, caused by Phytophthora ramorum, kills many, if not most of the coast live oaks, Quercus agrifolia, that become infected (McPherson and others, 2005). Several genera of ambrosia and bark beetles (Coleoptera: Scolytidae) colonize bleeding (infected) trees and are suspected to hasten tree death....

Altered expression of testis-specific genes, piRNAs, and transposons in the silkworm ovary masculinized by a W chromosome mutation

PubMed Central

2012-01-01

Background In the silkworm, Bombyx mori, femaleness is strongly controlled by the female-specific W chromosome. Originally, it was presumed that the W chromosome encodes female-determining gene(s), accordingly called Fem. However, to date, neither Fem nor any protein-coding gene has been identified from the W chromosome. Instead, the W chromosome is occupied with numerous transposon-related sequences. Interestingly, the silkworm W chromosome is a source of female-enriched PIWI-interacting RNAs (piRNAs). piRNAs are small RNAs of 23-30 nucleotides in length, which are required for controlling transposon activity in animal gonads. A recent study has identified a novel mutant silkworm line called KG, whose mutation in the W chromosome causes severe female masculinization. However, the molecular nature of KG line has not been well characterized yet. Results Here we molecularly characterize the KG line. Genomic PCR analyses using currently available W chromosome-specific PCR markers indicated that no large deletion existed in the KG W chromosome. Genetic analyses demonstrated that sib-crosses within the KG line suppressed masculinization. Masculinization reactivated when crossing KG females with wild type males. Importantly, the KG ovaries exhibited a significantly abnormal transcriptome. First, the KG ovaries misexpressed testis-specific genes. Second, a set of female-enriched piRNAs was downregulated in the KG ovaries. Third, several transposons were overexpressed in the KG ovaries. Conclusions Collectively, the mutation in the KG W chromosome causes broadly altered expression of testis-specific genes, piRNAs, and transposons. To our knowledge, this is the first study that describes a W chromosome mutant with such an intriguing phenotype. PMID:22452797

Determination of Albendazole and Metabolites in Silkworm Bombyx mori Hemolymph by Ultrafast Liquid Chromatography Tandem Triple Quadrupole Mass Spectrometry

PubMed Central

Li, Li; Xing, Dong-Xu; Li, Qing-Rong; Xiao, Yang; Ye, Ming-Qiang; Yang, Qiong

2014-01-01

Albendazole is a broad-spectrum parasiticide with high effectiveness and low host toxicity. No method is currently available for measuring albendazole and its metabolites in silkworm hemolymph. This study describes a rapid, selective, sensitive, synchronous and reliable detection method for albendazole and its metabolites in silkworm hemolymph using ultrafast liquid chromatography tandem triple quadrupole mass spectrometry (UFLC-MS/MS). The method is liquid-liquid extraction followed by UFLC separation and quantification in an MS/MS system with positive electrospray ionization in multiple reaction monitoring mode. Precursor-to-product ion transitions were monitored at 266.100 to 234.100 for albendazole (ABZ), 282.200 to 208.100 for albendazole sulfoxide (ABZSO), 298.200 to 159.100 for albendazole sulfone (ABZSO2) and 240.200 to 133.100 for albendazole amino sulfone (ABZSO2-NH2). Calibration curves had good linearities with R2 of 0.9905–0.9972. Limits of quantitation (LOQs) were 1.32 ng/mL for ABZ, 16.67 ng/mL for ABZSO, 0.76 ng/mL for ABZSO2 and 5.94 ng/mL for ABZSO2-NH2. Recoveries were 93.12%–103.83% for ABZ, 66.51%–108.51% for ABZSO, 96.85%–105.6% for ABZSO2 and 96.46%–106.14% for ABZSO2-NH2, (RSDs <8%). Accuracy, precision and stability tests showed acceptable variation in quality control (QC) samples. This analytical method successfully determined albendazole and its metabolites in silkworm hemolymph in a pharmacokinetic study. The results of single-dose treatment suggested that the concentrations of ABZ, ABZSO and ABZSO2 increased and then fell, while ABZSO2-NH2 level was low without obvious change. Different trends were observed for multi-dose treatment, with concentrations of ABZSO and ABZSO2 rising over time. PMID:25255321

Determination of albendazole and metabolites in silkworm Bombyx mori hemolymph by ultrafast liquid chromatography tandem triple quadrupole mass spectrometry.

PubMed

Li, Li; Xing, Dong-Xu; Li, Qing-Rong; Xiao, Yang; Ye, Ming-Qiang; Yang, Qiong

2014-01-01

Albendazole is a broad-spectrum parasiticide with high effectiveness and low host toxicity. No method is currently available for measuring albendazole and its metabolites in silkworm hemolymph. This study describes a rapid, selective, sensitive, synchronous and reliable detection method for albendazole and its metabolites in silkworm hemolymph using ultrafast liquid chromatography tandem triple quadrupole mass spectrometry (UFLC-MS/MS). The method is liquid-liquid extraction followed by UFLC separation and quantification in an MS/MS system with positive electrospray ionization in multiple reaction monitoring mode. Precursor-to-product ion transitions were monitored at 266.100 to 234.100 for albendazole (ABZ), 282.200 to 208.100 for albendazole sulfoxide (ABZSO), 298.200 to 159.100 for albendazole sulfone (ABZSO2) and 240.200 to 133.100 for albendazole amino sulfone (ABZSO2-NH2). Calibration curves had good linearities with R2 of 0.9905-0.9972. Limits of quantitation (LOQs) were 1.32 ng/mL for ABZ, 16.67 ng/mL for ABZSO, 0.76 ng/mL for ABZSO2 and 5.94 ng/mL for ABZSO2-NH2. Recoveries were 93.12%-103.83% for ABZ, 66.51%-108.51% for ABZSO, 96.85%-105.6% for ABZSO2 and 96.46%-106.14% for ABZSO2-NH2, (RSDs <8%). Accuracy, precision and stability tests showed acceptable variation in quality control (QC) samples. This analytical method successfully determined albendazole and its metabolites in silkworm hemolymph in a pharmacokinetic study. The results of single-dose treatment suggested that the concentrations of ABZ, ABZSO and ABZSO2 increased and then fell, while ABZSO2-NH2 level was low without obvious change. Different trends were observed for multi-dose treatment, with concentrations of ABZSO and ABZSO2 rising over time.

Proceedings of the Sudden Oak Death Fourth Science Symposium

Treesearch

Susan J. Frankel; John T. Kliejunas; Katharine M. Palmieri

2010-01-01

The Sudden Oak Death Fourth Science Symposium provided a forum for current research on sudden oak death, caused by the exotic, quarantine pathogen, Phytophthora ramorum. Ninety submissions describing papers or posters on the following sudden oak death/P. ramorum topics are included: biology, genetics, nursery and wildland...

Three Colopterus beetle species carry the oak wilt fungus to fresh wounds on red oak in Missouri

Treesearch

Maya Hayslett; Jennifer Juzwik; Bruce Moltzan

2008-01-01

Beetles in the family Nitidulidae can transmit the oak wilt fungus, Ceratocystis fagacearum, to fresh wounds on healthy oak trees, leading to infection and disease development. Historically, nitidulid beetles have not been considered important vectors of the pathogen in Missouri. Studies were conducted in the spring of 2005 and 2006 to determine...

Germination Characteristics of Engelmann Oak and Coast Live Oak from the Santa Rosa Plateau, Riverside County, California

Treesearch

Gerald E. Snow

1991-01-01

Over 2,000 acorns of Quercus agrifolia (coast live oak) and over 500 acorns of Q. engelmannii (Engelmann oak) were collected in the Jim Knight pasture area of the Santa Rosa Plateau. These were used to test for temperature and moisture conditions on germination of viable acorns in the laboratory under controlled environmental...

Pollen morphology and plant taxonomy of red oaks in eastern North America

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

Solomon, A.M.

Identification of Quercus (oak) pollen taxa could enhance Quaternary palynological interpretations from eastern North America. A first step is to determine a morphological and taxonomic basis for such identifications. Scanning electron microscopy was utilized to examine exine-surface features of 266 specimens representing 21 red oak (subgen. Erythrobalanus) species from eastern North America, and two intermediate oak (subgen. Protobalanus) species from the desert southwest. Twenty pollen morphological characteristics defined previously were tabulated for each of 324 pollen grains. The data were subjected to cluster analyses. Cluster diagrams were compared with traditional oak systematics. Pollen morphology and plant taxonomy compared poorly withmore » respect to series and species relationships among the red oaks, apparently due as much to high intraspecific and low interspecific variability in pollen-morphological characters as to the uncertain taxonomy of red oaks. Pollen morphology, however, does support the hypothesis of subgeneric oak evolution from intermediate oaks to the series Virentes of white oaks, and from more advanced white oaks to the red oak species. 19 references, 25 figures, 1 table.« less

Proceedings of the sudden oak death third science symposium

Treesearch

Susan J. Frankel; John T. Kliejunas; Katharine M. Palmieri

2008-01-01

The Sudden Oak Death Third Science Symposium provided a forum for current research on sudden oak death, caused by the exotic, quarantine pathogen, Phytophthora ramorum. One hundred and seventeen submissions describing papers and posters on the following sudden oak death/ P. ramorum topics are included: biology, genetics, nursery,...

Proceedings of the sudden oak death sixth science symposium

Treesearch

Susan J. Frankel; Katharine M. Harrell

2017-01-01

The Sudden Oak Death Sixth Science Symposium provided a forum for current research on sudden oak death, caused by the exotic quarantine pathogen Phytophthora ramorum. More than 50 submissions describing papers or posters on the following sudden oak death/P. ramorum topics are included: biology, genetics, nursery and wildland...

Factors limiting recruitment in valley and coast live oak

Treesearch

Claudia M. Tyler; Bruce E. Mahall; Frank W. Davis; Michael Hall

2002-01-01

The Santa Barbara County Oak Restoration Program was initiated in 1994 to determine the major factors limiting recruitment of valley oak (Quercus lobata) and coast live oak (Q. agrifolia). At Sedgwick Reserve in Santa Barbara County, California, we have replicated large-scale planting experiments in four different years to...

Goldspotted oak borer: Field identification guide

Treesearch

S. Hishinuma; T.W. Coleman; M.L. Flint; S.J. Seybold

2011-01-01

The goldspotted oak borer (GSOB), Agrilus auroguttatus (Coleoptera: Buprestidae), is a flatheaded borer new to California that poses a significant threat to oak trees. The pest is native to southeastern Arizona, although a related species occurs in southern Mexico and northern Guatemala. GSOB was first collected and identified in California in 2004 in San Diego County...

Release of suppressed oak advance regeneration

Treesearch

Dylan Dillaway; Jeffrey W. Stringer

2006-01-01

Oaks are not consistently regenerating on intermediate- and high-quality sites due to the lack of well-developed advance regeneration. Studies of northern red oak (Quercus rubra L.) seedling cohorts have shown that when grown under well-developed canopies and mid-stories, height growth is suppressed, and seedling mortality increases with time resulting in a sparsely...

Potential effects of sudden oak death on small mammals and herpetofauna in coast live oak (Quercus agrifolia woodlands

Treesearch

Douglas J. Tempel; William D. Tietje

2006-01-01

Within San Luis Obispo County, California, coast live oak (Quercus agrifolia) woodlands provide important habitat for many wildlife species (see Tietje and others, this volume). Unfortunately, many of these woodlands are at high risk of sudden oak death (SOD) infection should the pathogen (Phytophthora ramorum) become established...

White Oak Creek Watershed: Melton Valley Area Remedial Investigation Report, Oak Ridge National Laboratory, Oak Ridge, Tennessee: Volume 3 Appendix C

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

NONE

This report provides details on the baseline ecological risk assessment conducted in support of the Remedial Investigation (RI) Report for the Melton Valley areas of the White Oak Creek watershed (WOCW). The RI presents an analysis meant to enable the US Department of Energy (DOE) to pursue a series of remedial actions resulting in site cleanup and stabilization. The ecological risk assessment builds off of the WOCW screening ecological risk assessment. All information available for contaminated sites under the jurisdiction of the US Department of Energy`s Comprehensive Environmental Response, Compensation, and Liability Act Federal Facilities Agreement within the White Oakmore » Creek (WOC) RI area has been used to identify areas of potential concern with respect to the presence of contamination posing a potential risk to ecological receptors within the Melton Valley area of the White Oak Creek watershed. The risk assessment report evaluates the potential risks to receptors within each subbasin of the watershed as well as at a watershed-wide scale. The WOC system has been exposed to contaminant releases from Oak Ridge National Laboratory and associated operations since 1943 and continues to receive contaminants from adjacent waste area groupings.« less

Modeling 9-Year Survival Of Oak Advance Regeneration Under Shelterwood Overstories

Treesearch

Martin A. Spetich; David L. Graney

2004-01-01

Abstract Survival of white oak (Quercus alba L.), northern red oak (Q. rubra L.), and black oak (Q. velutina Lam.) on upland oak stands was modeled 9 years after shelterwood treatment. Stands represented a range of site quality, overstory stocking, and understory treatments. There were three...

A guide for evaluating the adequacy of oak advance reproduction.

Treesearch

Ivan L. Sander; Paul S. Johnson; Richard F. Watt

1976-01-01

Gives instructions for conducting an inventory of oak advance reproduction prior to final harvest cutting to evaluate the potential for successful oak reproduction in new stands. The potential for oak stump sprouting is also considered.

Forest stand dynamics and sudden oak death: Mortality in mixed-evergreen forests dominated by coast live oak

Treesearch

L.B. Brown; B. Allen-Diaz

2009-01-01

Sudden oak death (SOD), caused by the recently discovered non-native invasive pathogen, Phytophthora ramorum, has already killed tens of thousands of native coast live oak and tanoak trees in California. Little is known of potential short and long term impacts of this novel plant–pathogen interaction on forest structure and composition. Coast live...

The oak (Quercus) biodiversity of California and adjacent regions

Treesearch

Kevin C. Nixon

2002-01-01

Twenty species of oak (Quercus) are known from California. The white oak group is the most diverse, and includes a complex of scrub oak species that are often encountered in chaparral, mixed forest and desert margin habitats. The Protobalanus group (e.g., Quercus chrysolepis) is a unique and distinctive clade of western North...

Will Garry oak respond to release from overtopping conifers

Treesearch

Constance A. Harrington; Christel C. Kern

2002-01-01

Garry oak (Quercus garryana) woodlands provide unique habitat for many Pacific Northwest species but these habitats are rapidly disappearing as species composition shifts to conifer or land use changes to urban or agricultural. Many oak trees from former savannas or oak woodlands on Fort Lewis Military Reservation (near Tacoma, WA, USA) are currently...

A novel cytochrome P450 gene (CYP4G25) of the silkmoth Antheraea yamamai: cloning and expression pattern in pharate first instar larvae in relation to diapause.

PubMed

Yang, Ping; Tanaka, Hiromasa; Kuwano, Eiichi; Suzuki, Koichi

2008-03-01

A new cytochrome P450 gene, CYP4G25, was identified as a differentially expressed gene between the diapausing and post-diapausing pharate first instar larvae of the wild silkmoth Antheraea yamamai, using subtractive cDNA hybridization. The cDNA sequence of CYP4G25 has an open reading frame of 1674 nucleotides encoding 557 amino acid residues. Sequence analysis of the putative CYP4G25 protein disclosed the motif FXXGXRXCXG that is essential for heme binding in P450 cytochromes. Hybridization in situ demonstrated predominant expression of CYP4G25 in the integument of pharate first instar larvae. Northern blotting analysis showed an intensive signal after the initiation of diapause and no or weak expression throughout the periods of pre-diapause and post-diapause, including larval development. These results indicate that CYP4G25 is strongly associated with diapause in pharate first instar larvae.

Long-term trends in coast live oak and tanoak stands affected by Phytophthora ramorum canker (Sudden Oak Death)

Treesearch

Tedmund J. Swiecki; Elizabeth Bernhardt

2010-01-01

Permanent plots were established in 2000 to examine how tree and site factors affect risk of Phytophthora ramorum stem canker (sudden oak death [SOD]) and determine how affected stands change over time due to disease. P. ramorum canker was prevalent in the sampled coast live oak (Quercus agrifolia) or...

Evaluation of spectral light management on growth of container-grown willow oak, nuttall oak and summer red maple

USDA-ARS?s Scientific Manuscript database

Plant response to blue, red, gray or black shade cloth was evaluated with willow oak (Quercus phellos L.), Nuttall oak (Quercus nuttallii Palmer, Nuttall) and Summer Red maple (Acer rubrum L. ‘Summer Red’) liners. Light transmitted through the colored shade cloth had no influence on germination of ...

Oak Grove Fork Habitat Improvement Project, 1988 Annual Report.

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

Bettin, Scott

The Lower Oak Grove Fork of the Clackamas River is a fifth-order tributary of the Clackamas River drainage supporting depressed runs of coho and chinook salmon, and summer and winter steelhead. Habitat condition rating for the Lower Oak Grove is good, but smelt production estimates are below the average for Clackamas River tributaries. Limiting factors in the 3.8 miles of the Lower Oak Grove supporting anadromous fish include an overall lack of quality spawning and rearing habitat. Beginning in 1986. measures to improve fish habitat in the Lower Oak Grove were developed in coordination with the Oregon Department of Fishmore » and Wildlife (ODF&W) and Portland General Electric (PGE) fisheries biologists. Prior to 1986, no measures had been applied to the stream to mitigate for PGE's storage and regulation of flows in the Oak Grove Fork (Timothy Lake, Harriet Lake). Catchable rainbow trout are stocked by ODF&W two or three times a year during the trout fishing season in the lowermost portion of the Oak Grove Fork near two Forest Service campgrounds (Ripplebrook and Rainbow). The 1987 field season marked the third year of efforts to improve fish habitat of the Lower Oak Grove Fork and restore anadromous fish production. The efforts included the development of an implementation plan for habitat improvement activities in the Lower Oak Grove Fork. post-project monitoring. and maintenance of the 1986 improvement structures. No new structures were constructed or placed in 1987. Fiscal year 1988 brought a multitude of changes which delayed implementation of plans developed in 1987. The most prominent change was the withdrawal of the proposed Spotted Owl Habitat Area (SOHA) which overlapped the Oak Grove project implementation area. Another was the change in the Forest Service biologist responsible for implementation and design of this project.« less

Regeneration of oaks by direct seeding

Treesearch

R. Johnson; R. Krinard

1985-01-01

Direct sowing of oak acorns has not always met with success. This paper summarizes recent research regarding direct sowing of oaks in research plots and commercial trials. Present findings indicate that seedlings can be established from properly stored acorns sown any month of the year by hand or machine. They should be sown at a 2-inch depth, although they can be sown...

Accelerating oak air drying by presurfacing

Treesearch

W. T. Simpson; R. C. Baltes

1972-01-01

A comparison was made between the air-drying rates of rough and presurfaced northern red oak and white oak. In both species, the presurfaced material was about 1/8 inch thinner than the rough material and dried faster than the rough material. The reduction in drying time depends on the method of analyzing the drying curves, but is slightly less than 10 percent.

Fire Effects in Blue Oak Woodland

Treesearch

Patricia K. Haggerty

1991-01-01

Mortality and resprouting of shrubs and trees were assessed in one recent fire and 11 older burns in blue oak woodland in the southern Sierra Nevada foothills. This poster reported results for blue oak. Survival following fire was high; with a 93 percent two year postfire survival rate after one intensively studied fire, despite a large number of trees with 100 percent...

Population diversity and evidence of introgression among the black oaks of California

Treesearch

Richard S. Dodd; Nasser Kashani; Zara Afzal-Rafii

2002-01-01

The black oaks of California include 4 tree species (California black oak, coast live oak, Shreve oak, interior live oak) that are known to hybridize. Complex patterns of population variation within each species are likely to result from these hybrid combinations and from subsequent introgressions. We have been studying population variation using biochemical and...

Manufacture of oak furniture, cabinets, and panels

Treesearch

Harold C. Moser

1971-01-01

Oak is uniquely favored for use in furniture, cabinets, and similar products. The supply is plentiful. Though drying presents some problems, once oak is properly dried it is a stable wood that machines very well, glues well, and accepts a variety of finishes well.

Estimating fire-caused mortality and injury in oak-hickory forests.

Treesearch

Robert M. Loomis

1973-01-01

Presents equations and graphs for predicting fire-caused tree mortality and equations for estimating basal wound dimensions for surviving trees. The methods apply to black oak, white oak, and some other species of the oak-hickory forest type.

The ancient blue oak woodlands of California: longevity and hydroclimatic history

USGS Publications Warehouse

Stahle, D.W.; Griffin, R.D.; Meko, D.M.; Therrell, M.D.; Edmondson, J.R.; Cleaveland, M.K.; Burnette, D.J.; Abatzoglou, J.T.; Redmond, K.T.; Dettinger, M.D.; Cayan, D.R.

2013-01-01

Ancient blue oak trees are still widespread across the foothills of the Coast Ranges, Cascades, and Sierra Nevada in California. The most extensive tracts of intact old-growth blue oak woodland appear to survive on rugged and remote terrain in the south Coast Ranges and on the foothills west and southwest of Mt. Lassen. In our sampling of old-growth stands, most blue oak appear to have recruited to the canopy in the mid- to late-19th century. The oldest living blue oak tree sampled was over 459-years old and several dead blue oak logs had over 500 annual rings. Precipitation sensitive tree-ring chronologies up to 700-years long have been developed from old blue oak trees and logs. Annual ring-width chronologies of blue oak are strongly correlated with cool season precipitation totals, streamflow in the major rivers of California, and the estuarine water quality of San Francisco Bay. A new network of 36 blue oak chronologies records spatial anomalies in growth that arise from latitudinal changes in the mean storm track and location of landfalling atmospheric rivers. These long, climate-sensitive blue oak chronologies have been used to reconstruct hydroclimatic history in California and will help to better understand and manage water resources. The environmental history embedded in blue oak growth chronologies may help justify efforts to conserve these authentic old-growth native woodlands.

A new book: the ecology and silviculture of oaks

Treesearch

Stephen R. Shifley; Robert Rogers

2003-01-01

A new book, The Ecology and Silviculture of Oaks, is now available (Johnson and others 2002). The book focuses on the oaks of the United States and was written for forest and wildlife managers, ecologists, silviculturists, environmentalists, students of those fields, and others interested in sustaining oak forests for their many tangible and intangible values. Although...

Maximum crown area equation for open-grown bur oak

Treesearch

M.C. Demchik; S.M. Virden; Z.L. Buchanan; A.M. Johnson

2017-01-01

Bur oak (Quercus macrocarpa Michx.) is a classic savanna species with a range that covers much of the eastern United States. Because savannas are an endangered habitat in North America, significant restoration efforts are in progress across much of the range of bur oak. For open sites being planted with bur oaks as well as fully stocked sites that...

Oak decline risk rating for the southeastern United States

Treesearch

S. Oak; F. Tainter; J. Williams; D. Starkey

1996-01-01

Oak decline risk rating models were developed for upland hardwood forests in the southeastern United States using data gathered during regional oak decline surveys. Stepwise discriminant analyses were used to relate 12 stand and site variables with major oak decline incidence for each of three subregions plus one incorporating all subregions. The best model for the...

BmICE-2 is a novel pro-apoptotic caspase involved in apoptosis in the silkworm, Bombyx mori.

PubMed

Yi, Hua-Shan; Pan, Cai-Xia; Pan, Chun; Song, Juan; Hu, Yan-Fen; Wang, La; Pan, Min-Hui; Lu, Cheng

2014-02-28

In this study we identified a potential pro-apoptotic caspase gene, Bombyx mori(B. mori)ICE-2 (BmICE-2) which encoded a polypeptide of 284 amino acid residues, including a (169)QACRG(173) sequence which surrounded the catalytic site and contained a p20 and a p10 domain. BmICE-2 expressed in Escherichia coli (E. coli) exhibited high proteolytic activity for the synthetic human initiator caspase-9 substrates Ac-LEHD-pNA, but little activity towards the effector caspase-3 substrates Ac-DEVD-pNA. When BmICE-2 was transiently expressed in BmN-SWU1 silkworm B. mori cells, we found that the high proteolytic activity for Ac-LEHD-pNA triggered caspase-3-like protease activity resulting in spontaneous cleavage and apoptosis in these cells. This effect was not replicated in Spodoptera frugiperda 9 cells. In addition, spontaneous cleavage of endogenous BmICE-2 in BmN-SWU1 cells could be induced by actinomycin D. These results suggest that BmICE-2 may be a novel pro-apoptotic gene with caspase-9 activity which is involved apoptotic processes in BmN-SWU1 silkworm B. mori cells. Copyright © 2014 Elsevier Inc. All rights reserved.

Impact of the goldspotted oak borer, Agrilus auroguttatus, on the health of coast live oak before and after treatment with two systemic insecticides

Treesearch

Yigen Chen; Mary L. Flint; Tom W. Coleman; Joseph J. Doccola; Donald M. Grosman; David L. Wood; Steven J. Seybold

2015-01-01

BACKGROUND: The invasive goldspotted oak borer, Agrilus auroguttatus, is threatening the health and survival of oak trees in San Diego County, California. From two sites in the core area of the infestation, we report a 2.5 year investigation of the impact of A. auroguttatus on coast live oak, Quercus agrifolia, before and after treatment with two systemic...

Improved isolation and purification of functional human Fas receptor extracellular domain using baculovirus-silkworm expression system.

PubMed

Muraki, Michiro; Honda, Shinya

2011-11-01

To achieve an efficient isolation of human Fas receptor extracellular domain (hFasRECD), a fusion protein of hFasRECD with human IgG1 heavy chain Fc domain containing thrombin cleavage sequence at the junction site was overexpressed using baculovirus-silkworm larvae expression system. The hFasRECD part was separated from the fusion protein by the effective cleavage of the recognition site with bovine thrombin. Protein G column treatment of the reaction mixture and the subsequent cation-exchange chromatography provided purified hFasRECD with a final yield of 13.5mg from 25.0 ml silkworm hemolymph. The functional activity of the product was examined by size-exclusion chromatography analysis. The isolated hFasRECD less strongly interacted with human Fas ligand extracellular domain (hFasLECD) than the Fc domain-bridged counterpart, showing the contribution of antibody-like avidity in the latter case. The purified glycosylated hFasRECD presented several discrete bands in the disulphide-bridge non-reducing SDS-PAGE analysis, and virtually all of the components were considered to participate in the binding to hFasLECD. The attached glycans were susceptible to PNGase F digestion, but mostly resistant to Endo Hf digestion under denaturing conditions. One of the components exhibited a higher susceptibility to PNGase F digestion under non-denaturing conditions. Copyright © 2011 Elsevier Inc. All rights reserved.

Oak ecosystem succession of the Northern Caucasus

NASA Astrophysics Data System (ADS)

Chalaya, Elena; Slepykh, Victor; Efimenko, Natalia; Povolotskaya, Nina

2014-05-01

English oak (Quercus robur L.) along with its well-known good properties has a high sanitary-hygienic and curative potential. Its volatile metabolites (VM) influence bacteriostatically Staphylococcus aureus 209r, oppressing it in vitro by 85% compared with the control, and Escherichia coli by 45%. There is the least amount of epiphytic microorganisms on the leaves of Q. robur L. compared with some tree species [1]. In addition, VM of Q. robur L. have direct milieu (hypotensive) effects on the organism under its canopy, lowering blood pressure by 20-25 mm Hg [2]. A.P. Kazankin (1993) [4] calculated the prehistoric formula of forest species composition of Caucasian Mineral Waters region (Northern Caucasus): 6Qr3Crp1Fr which was based on the theory of calcium-magnesium absorption complex. According to the theory, underground mineral water, soil, forest litter and the leaves of ground vegetation of the area have the same ratio of the cations Ca and Mg - calcium-magnesium index [3]. Hence oldgrowth in the region consisted of oak (Qr) by 60%, hornbeam (Carpinus-Crp) by 30% and ash (Fraxinus-Fr) only by 10%. Currently, the formula of the forests of the region has been changed by man: 5Fr3Crp2Qr. The proportion of oak forests has decreased to 20%, the proportion of ash has increased by 50%, but the proportion of hornbeam hasn't changed. So it is relevant to restore oak forests of the region in the former ratio to other forest-forming species - ash and hornbeam. Taking into consideration the change of economic formation of society in Russia, it is extremely important to restore natural seed oak forests. Therein the luminance of surface areal is a limiting factor. We have calculated that the natural recovery of oak forests is possible providing observation of optimal moisture standards and soil fertility in combination with solar light within 10-24% from the light of open space. Measures for promotion of oak natural regeneration in mountain resorts of the Northern Caucasus

Gypsy moth (Lepidoptera: Lymantriidae) consumption and utilization of northern red oak and white oak foliage exposed to simulated acid rain and ozone

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

Cannon, W.N. Jr.

1993-06-01

Two-year-old seedlings of white oak, Quercus alba L., and red oak, Q. rubra L., were exposed to ozone (O[sub 3]) fumigations in four continuously stirred tank reactor chambers in the greenhouse for 8 h/d, 3 d/wk for 6 wk. Fumigation treatments were charcoal-filtered air (CFA) and CFA + 0.15 ppm O[sub 3]. Two simulated rain treatments, pH 4.2 and pH 3.0, of-1.25 cm were applied once each week in rain-simulation chambers. Gypsy moth, Lymantria dispar (L.), third instars were allowed to feed on leaf disks from treated seedlings for 24 h. Leaf area consumed, food assimilated, weight gain, and relativemore » growth rate (RGR) were examined. Overall, larvae fed white oak foliage consumed more foliage and gained more weight than those fed red oak foliage. Response to the fumigation and rain treatments was different for each oak species. On white oak foliage, larvae consumed significantly less foliage treated with CFA + pH 3.0 rain, but the lowest RGR occurred with the 0.15 ppm O[sub 3] + pH 4.2 rain treatment. The most food assimilated, greatest weight gain, and highest RGR occurred with the CFA + pH 4.2 rain control. Red oak foliage consumed was equivalent for all treatments, but foliage exposed to CFA + pH 3.0 rain resulted in more food assimilated, greater weight gain, and higher RGR for that species.« less

Oak Decline in Missouri: History Revisited

Treesearch

Jay R. Law; Ross Melick; Charly Studyvin; James R. Steinman

2004-01-01

In the 1980s, following extreme winters in the late 1970s and severe droughts in 1976, 1980, and 1983, dead and dying scarlet and black oaks were found on 185,000 acres of the Mark Twain National Forest. That decline event was linked to environmental stresses (Law and Gott 1987). Severe oak decline is now affecting an estimated 500,000 acres on the Mark Twain. High-...

Coarse woody debris metrics in a California oak woodland

Treesearch

William D. Tietje; Michael A. Hardy; Christopher C. Yim

2015-01-01

Little information is available on the metrics of coarse woody debris (CWD) in California oak woodland, most notably at the scale of the stand and woodland type. In a remote part of the National Guard Post, Camp Roberts, that has not burned in over a half century, we tallied 314 pieces of CWD in a blue oak (Quercus douglasii)-coast live oak (

Welcome to the sudden oak death third science symposium

Treesearch

Susan J. Frankel

2008-01-01

On behalf of the United States Department of Agriculture (USDA)-Forest Service, Pacific Southwest Research Station and the California Oak Mortality Task Force, it is my pleasure to welcome you to the Sudden Oak Death Third Science Symposium. Looking back at the first sudden oak death science symposium held in Monterey in December 2002, it is amazing to see how far we...

How pallets with red oak deckboards performed in use

Treesearch

Robert S. Kurtenacker

1975-01-01

In-use tests in a combination brick and cement block yard and subsequent laboratory tests indicated that laminated pallet deckboards made from knife-cut, low-grade red oak logs can perform as well as deckboards of solid red oak. Performance was not significantly different between laminated oak deckboard pallets assembled with 2-l/2-in.-long by 15-gage staples and...

Chitin in the Silk Gland Ducts of the Spider Nephila edulis and the Silkworm Bombyx mori

PubMed Central

Davies, Gwilym J. G.; Knight, David P.; Vollrath, Fritz

2013-01-01

Here we report the detection and localisation of chitin in the cuticle of the spinning ducts of both the spider Nephila edulis and the silkworm Bombyx mori. Our observations demonstrate that the duct walls of both animals contain chitin notwithstanding totally independent evolutionary pathways of the systems. We conclude that chitin may well be an essential component for the construction of spinning ducts; we further conclude that in both species chitin may indicate the evolutionary origin of the spinning ducts. PMID:24015298

Phytophthora ramorum and sudden oak death in California: II. transmission and survival

Treesearch

Jennifer M. Davidson; David M. Rizzo; Matteo Garbelotto; Steven Tjosvold; Garey W. Slaughter

2002-01-01

The newly discovered Phytophthora ramorum canker disease of oak (Sudden Oak Death Syndrome) threatens millions of acres of California woodlands where coast live oak (Quercus agrifolia), tanoak (Lithocarpus densiflorus), or black oak (Quercus kelloggii) are dominant species. An important step in...

Forest regeneration composition and development in upland, mixed-oak forests.

PubMed

Fei, Songlin; Gould, Peter J; Steiner, Kim C; Finley, James C; McDill, Marc E

2005-12-01

Advance regeneration in 52 mature mixed-oak stands was analyzed and described. Red maple (Acer rubrum L.) was the most abundant species in the study area. Among oak (Quercus) species, northern red oak (Q. rubra L.) was the most abundant within the Allegheny Plateau physiographic province, whereas chestnut oak (Q. montana L.) was the most abundant within the Ridge and Valley physiographic province. Sixteen stands, for which data are available through the fourth growing season following harvest, were used to describe stand development. Cumulative height, a composite measure of size and density, was used to describe early stand development. Black gum (Nyssa sylvatica Marsh.) and black birch (Betula lenta L.) had dramatic increases in stand density and cumulative height after overstory removal. Cumulative height of northern red oak and chestnut oak showed a faster positive response to overstory removal than red maple. Oak retained its dominance in cumulative height for at least 4 years after harvest. Red maple nevertheless remained the most abundant tree species after overstory removal. Our results suggest that the principal advantage of red maple regeneration is its ability to accumulate in large numbers prior to harvest.

Ecological evidence of intensive cultivation of oaks by California Indians: implications for the treatment of sudden oak death

Treesearch

Lee Klinger

2006-01-01

The native oaks of California are remarkable for being among the oldest and largest oak trees in the United States besides their great age and size, these trees possess various idiosyncrasies in their arrangements and shapes that appear to defy basic principles of ecology and population biology. When taken together, these and other associated patterns present an...

Planting native oak in the Pacific Northwest

Treesearch

Warren D. Devine; Constance A. Harrington

2010-01-01

The extent of oak woodland and savanna habitat in the Pacific Northwest has been dramatically reduced since settlement in the mid-1800s. This report presents a practical guide for landowners and managers who are interested in reestablishing native oak by planting seedlings. Keys to successful establishment are (1) planting quality...

Genetic hitch-hiking extends the range of coast live oak

Treesearch

Richard S. Dodd; Zara Afzal-Rafii; Wasima Mayer

2006-01-01

The northernmost range of coast live oak (Quercus agrifolia) is reported from the Ukiah Valley (Mendocino County, California). Here, field observations suggest that hybridization with interior live oak (Q. wislizeni) is important. Elsewhere in northern California, morphology of coast live oak can be highly variable (particularly...

Fire and Thinning Effects on Oak Regeneration in Southern Ohio

Treesearch

Dave Apsley; Dan Yaussy

2005-01-01

Oaks dominate a large percentage of the forests in southern Ohio. But, have you ever looked at the seedlings and saplings that are regenerating under these predominately oak canopies? Typically very little oak and often the seedlings and saplings are red maple, sugar maple and American beech.

Blue and Valley Oak Seedling Establishment on California's Hardwood Rangelands

Treesearch

Theodore E. Adams Jr.; Peter B. Sands; William H. Weitkamp; Neil K. McDougald

1991-01-01

Factors contributing to poor establishment of blue oak (Quercus douglasii) and valley oak (Q. lobata) in California oak-grassland savannas were studied in a series of acorn seeding experiments initiated in 1985. Exclusion of large herbivores permitted examination of herbaceous interference and small mammal and insect depredation....

Shumard Oaks Successfully Planted on High pH Soils

Treesearch

Harvey E. Kennedy; Roger M. Krinard

1985-01-01

Shumard oak was successfully planted on high pH (7.8-8.0) Mississippi River alluvium soils where some other planted red oaks had failed. Survival and growth have been good through ages 10, 11, and 25 years in three separate plantings. Shumard oak on high pH soils, in addition to producing timber, would allow a consistent mast-producing tree on sites normally void of...

How to identify and manage oak wilt in Texas

Treesearch

D. N. Appel; R. S. Cameron; A. D. Wilson; J. D. Johnson.

2008-01-01

Measures can be taken to break root connections between live oaks or dense groups of red oaks to reduce or stop root transmission of the oak wilt fungus. The most common technique is to sever roots by trenching at least 4 ft deep with trenching machines, rock saws, or ripper bars. Trenches more than 4 ft deep may be needed to assure control in deeper soils. Although...

Oak Decline

Treesearch

Vernon Ammon; T. Evan Nebeker; Ted H. Filer; Francis I. McCracken; J. D. Solomon; H. E. Kennedy

1989-01-01

Occurrence of decline and mortality in this nation's hardwood forests has been documented in reports for the past 130 years. From 1856 through 1981, more than 26 decline events were reported from eight eastern states affecting almost all species of oaks. Fourteen factors have been implicated as either primary or secondary agents responsible for decline and...

Thinking About Oak Forests as Responsive Ecosystems

Treesearch

Paul S. Johnson

2004-01-01

Like all forests, oak forests are continually responding to disturbances originating from both within and outside the forest. Oaks (Quercus spp.) owe their very existence to disturbance. In this context, silvicultural and other manage-ment practices can be thought of as planned disturbances designed to direct forest change in specific ways. The...

Identification of plasmalogen in the gut of silkworm (Bombyx mori).

PubMed

Aboshi, Takako; Nishida, Ritsuo; Mori, Naoki

2012-08-01

Herbivorous insect species are constantly challenged with endogenous and exogenous oxidative stress. Consequently, they possess an array of antioxidant enzymes and small molecular weight antioxidants. Lipid-soluble small molecular antioxidants, such as tocopherols, have not been well studied in insects but may play important antioxidant roles. In this study, we identified plasmalogen phosphatidylethanolamines (pPEs) as well as α-, β/γ-, δ-tocopherol in the larvae of the silkworm Bombyx mori by LCMS analyses and examined their distribution. Plasmalogen are reported to inhibit the metal ion induced oxidation. The composition of tocopherols was the same among gut contents, gut tissues, and the other tissues. However, plasmalogens, a unique class of glycerophospholipids rich in polyunsaturated fatty acids and containing a vinyl ether bond at the sn-1 position, were mainly distributed in gut tissues. Plasmalogens might protect gut tissues from oxidation stress. Copyright © 2012 Elsevier Ltd. All rights reserved.

Monitoring for pests and diseases in native oak woodlands: the case of acute oak decline in the United Kingdom

Treesearch

Nathan Brown; Stephen Parnell; Frank van den Bosch; Mike Jeger; Sandra Denman

2017-01-01

In recent years, a novel form of decline has been observed in southern and central England. This syndrome has been termed acute oak decline (AOD) and affects native oak, Quercus petraea and Q. robur. Typical symptoms include bark cracks that weep dark exudates, which are caused by necrotic patches in the...

Correlation between fibroin amino acid sequence and physical silk properties.

PubMed

Fedic, Robert; Zurovec, Michal; Sehnal, Frantisek

2003-09-12

The fiber properties of lepidopteran silk depend on the amino acid repeats that interact during H-fibroin polymerization. The aim of our research was to relate repeat composition to insect biology and fiber strength. Representative regions of the H-fibroin genes were sequenced and analyzed in three pyralid species: wax moth (Galleria mellonella), European flour moth (Ephestia kuehniella), and Indian meal moth (Plodia interpunctella). The amino acid repeats are species-specific, evidently a diversification of an ancestral region of 43 residues, and include three types of regularly dispersed motifs: modifications of GSSAASAA sequence, stretches of tripeptides GXZ where X and Z represent bulky residues, and sequences similar to PVIVIEE. No concatenations of GX dipeptide or alanine, which are typical for Bombyx silkworms and Antheraea silk moths, respectively, were found. Despite different repeat structure, the silks of G. mellonella and E. kuehniella exhibit similar tensile strength as the Bombyx and Antheraea silks. We suggest that in these latter two species, variations in the repeat length obstruct repeat alignment, but sufficiently long stretches of iterated residues get superposed to interact. In the pyralid H-fibroins, interactions of the widely separated and diverse motifs depend on the precision of repeat matching; silk is strong in G. mellonella and E. kuehniella, with 2-3 types of long homogeneous repeats, and nearly 10 times weaker in P. interpunctella, with seven types of shorter erratic repeats. The high proportion of large amino acids in the H-fibroin of pyralids has probably evolved in connection with the spinning habit of caterpillars that live in protective silk tubes and spin continuously, enlarging the tubes on one end and partly devouring the other one. The silk serves as a depot of energetically rich and essential amino acids that may be scarce in the diet.

Oak Ridge reservation land-use plan

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

Bibb, W. R.; Hardin, T. H.; Hawkins, C. C.

1980-03-01

This study establishes a basis for long-range land-use planning to accommodate both present and projected DOE program requirements in Oak Ridge. In addition to technological requirements, this land-use plan incorporates in-depth ecological concepts that recognize multiple uses of land as a viable option. Neither environmental research nor technological operations need to be mutually exclusive in all instances. Unique biological areas, as well as rare and endangered species, need to be protected, and human and environmental health and safety must be maintained. The plan is based on the concept that the primary use of DOE land resources must be to implementmore » the overall DOE mission in Oak Ridge. This document, along with the base map and overlay maps, provides a reasonably detailed description of the DOE Oak Ridge land resources and of the current and potential uses of the land. A description of the land characteristics, including geomorphology, agricultural productivity and soils, water courses, vegetation, and terrestrial and aquatic animal habitats, is presented to serve as a resource document. Essentially all DOE land in the Oak Ridge area is being fully used for ongoing DOE programs or has been set aside as protected areas.« less

Armillaria root disease affects oak coppice regeneration in upland Missouri Ozark forests

Treesearch

J. N. Bruhn; D. C. Dey; K. K. Kromroy; J. D. Mihail; J. M. Kabrick; J. J., Jr. Wetteroff

2005-01-01

Coppice regeneration is favored in North America for oak (Quercus spp.) regeneration. Although models of oak stump sprouting do not consider Armillaria root disease, many oak stumps in upland Ozark forest stands carry active Armillaria root crown infections. The spatial pattern of sprouting on oak stumps is...

Influence of Scale on the Management of Wildlife in California Oak Woodlands

Treesearch

William M. Block; Michael L. Morrison

1991-01-01

Distributions, abundances, and patterns of resource use of amphibians, reptiles, birds, and small mammals varied spatially and temporally in California oak woodlands. Spatial variations occurred within stands, between stands of a similar type (e.g., canyon live oak [Quercus chrysolepis], blue oak [Q. douglasii], or valley oak [

Managing an oak decline crisis in Oakville, Ontario: lessons learned

Treesearch

Peter A. Williams; John W. McNeil; Kurt W. Gottschalk; Robert A. Haack

2013-01-01

The town of Oakville, Ontario, is located along the north shore of Lake Ontario between Toronto and Hamilton. In the fall of 2002, significant oak (Quercus spp.) mortality was observed at Oakville's Iroquois Shoreline Woods Park, an environmentally significant forest remnant noted for its oak-dominated forests. Investigations suggested that oak...

Planting oaks in the Central Hardwood Region: a shelterwood approach

Treesearch

Dale R. Weigel

1997-01-01

The success of oak seedlings planted under shelterwoods depends on where they are planted, initial seedling size, nursery undercutting treatments, and whether they are top-clipped before planting. These conclusions are based on planting northern red oak (Quercus rubra L.) and white oak (Q. alba L.) under shelterwoods in Indiana and...