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1

RNA-binding region of Macrobrachium rosenbergii nodavirus capsid protein.  

PubMed

White tail disease (WTD) kills prawn larvae and causes drastic losses to the freshwater prawn (Macrobrachium rosenbergii) industry. The main causative agent of WTD is Macrobrachium rosenbergii nodavirus (MrNV). The N-terminal end of the MrNV capsid protein is very rich in positively charged amino acids and is postulated to interact with RNA molecules. N-terminal and internal deletion mutagenesis revealed that the RNA-binding region is located at positions 20-29, where 80?% of amino acids are positively charged. Substitution of all these positively charged residues with alanine abolished the RNA binding. Mutants without the RNA-binding region still assembled into virus-like particles, suggesting that this region is not a part of the capsid assembly domain. This paper is, to the best of our knowledge, the first to report the specific RNA-binding region of MrNV capsid protein. PMID:24878641

Goh, Zee Hong; Mohd, Nur Azmina Syakirin; Tan, Soon Guan; Bhassu, Subha; Tan, Wen Siang

2014-09-01

2

In situ hybridization and RT-PCR detection of Macrobrachium rosenbergii nodavirus in giant freshwater prawn, Macrobrachium rosenbergii (de Man), in Taiwan.  

PubMed

Between January and March 2006, suspected outbreaks of white tail disease were observed in post-larvae and juveniles of Macrobrachium rosenbergii in hatcheries and nursery ponds at Kaohsiung and Pingtung Counties in southern Taiwan. Pathognomonic lesions showed the presence of large oval and/or irregular basophilic, cytoplasmic inclusion bodies in the infected muscles and hepatopancreas. Reverse transcriptase polymerase chain reaction (RT-PCR) assay and in situ hybridization (ISH) revealed evidence of M. rosenbergii nodavirus (MrNV) infection but did not detect extra small virus. Phylogenetic analysis indicated that there were very high identities between nucleotide sequences among six strains obtained in this study (99.5-100%), moderate identities with Caribbean and Indian strains (98.2-98.6%), but slightly lower identity with a Chinese strain (95.2%). This is the first confirmation of MrNV in giant freshwater prawns, using an RT-PCR and ISH, in Taiwan. PMID:17169113

Hsieh, C-Y; Wu, Z-B; Tung, M-C; Tu, C; Lo, S-P; Chang, T-C; Chang, C-D; Chen, S-C; Hsieh, Y-C; Tsai, S-S

2006-11-01

3

Experimental vertical transmission of Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus (XSV) from brooders to progeny in Macrobrachium rosenbergii and Artemia.  

PubMed

White tail disease (WTD) is a serious problem in hatcheries and nursery ponds of Macrobrachium rosenbergii in India. Experiments were carried out to determine the possibility of vertical transmission of M. rosenbergii nodavirus (MrNV) and extra small virus (XSV) in M. rosenbergii and Artemia. Prawn broodstock inoculated with MrNV and XSV by oral or immersion challenge survived without any clinical signs of WTD. The brooders spawned 5-7 days after inoculation and the eggs hatched. The survival rate of larvae gradually decreased, and 100% mortality was observed at the post-larvae (PL) stage. Whitish muscle, the typical sign of WTD, was seen in advanced larval developmental stages. The ovarian tissue and fertilized eggs were found to be positive for MrNV/XSV by reverse transcriptase-polymerase chain reaction (RT-PCR) whereas the larval stages showed positive by RT nested PCR (nRT-PCR). In Artemia, reproductive cysts and nauplii derived from challenged brooders were normal and survival rates were within the expected range for normal rearing conditions. The reproductive cysts were found to be positive for MrNV/XSV by RT-PCR whereas the nauplii showed MrNV/XSV-positive by nRT-PCR. The PL of M. rosenbergii fed nauplii derived from challenged Artemia brooders died at 9 days post-inoculum with clinical signs of WTD. PMID:17241402

Sudhakaran, R; Ishaq Ahmed, V P; Haribabu, P; Mukherjee, S C; Sri Widada, J; Bonami, J R; Sahul Hameed, A S

2007-01-01

4

Artemia as a possible vector for Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus transmission (XSV) to Macrobrachium rosenbergii post-larvae.  

PubMed

Five developmental stages of Artemia were exposed to Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus (XSV) by immersion and oral routes in order to investigate the possibility of Artemia acting as a reservoir or carrier of these viruses. The second objective was to determine if virus-exposed Artemia were capable of transmitting the disease to post-larvae (PL) of M. rosenbergii. There was no significant difference in percent mortality between Artemia control groups and groups challenged with these viruses. On the other hand, all the developmental stages of Artemia were positive for both viruses by nested RT-PCR, regardless of the challenge route. In horizontal transmission experiments, 100% mortality was observed in M. rosenbergii PL fed with Artemia nauplii exposed to MrNV and XSV by either challenge route. However, no mortality was observed in PL fed with virus-free Artemia. RT-PCR analysis of the M. rosenbergii PL confirmed the presence of MrNV and XSV in the challenge group and absence in the control group. PMID:16875403

Sudhakaran, R; Yoganandhan, K; Ahmed, V P Ishaq; Hameed, A S Sahul

2006-06-12

5

Clearance of Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus (XSV) and immunological changes in experimentally injected Macrobrachium rosenbergii.  

PubMed

Macrobrachium rosenbergii was experimentally challenged with Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus (XSV) to study the clearance of these viruses and consequent changes in various immunological parameters. The healthy animals were injected MrNV and XSV intramuscularly and various organ samples such as gill tissue, head soft tissue, pleopods and intestine were collected at different time intervals of 3, 5, 10, 15, 25, 50, 75 and 100d post-infection (p.i.) to study the viral clearance. Tissue tropism and clearing of MrNV and XSV were confirmed by RT-PCR, nested RT-PCR and bioassay. These 2 viruses failed to cause mortality or clinical signs of disease in injected adult prawns during the experimental period of 100 days. The result of RT-PCR analysis revealed that all the organs showed positive for both viruses by single step RT-PCR on 3, 5 and 10 d p.i., positive by nested RT-PCR on 15 and 20 d p.i. and all the organs became negative at 25 d p.i. onwards. The viral inoculum prepared from the tissue of MrNV and XSV-injected M. rosenbergii at 3, 5, 10, 15 and 20 d p.i. caused 100% mortality in post-larvae of M. rosenbergii at 9, 8, 7, 10 and 10 d p.i., respectively whereas the inoculum prepared at 25, 50 and 100 d p.i. failed to cause significant mortality in post-larvae of prawn. Immunological parameters such as proPO, superoxide anion, SOD, THC, clotting time and oxyhemocyanin were determined in MrNV and XSV-injected prawns and significant differences in some of the immunological parameters were found in the early days p.i. and became insignificant in the later days p.i. PMID:19963067

Ravi, M; Nazeer Basha, A; Taju, G; Ram Kumar, R; Sahul Hameed, A S

2010-03-01

6

Experimental transmission and tissue tropism of Macrobrachium rosenbergii nodavirus (MrNV) and its associated extra small virus (XSV).  

PubMed

White tail disease (WTD) was found to be a serious problem in hatcheries and nursery ponds of Macrobrachium rosenbergii in India. The causative organisms have been identified as M. rosenbergii nodavirus (MrNV) and its associated extra small virus (XSV). Experimentally transmitted to healthy animals, they caused 100% mortality in post-larvae but failed to cause mortality in adult prawns. The RT-PCR assay revealed the presence of both viruses in moribund post-larvae and in gill tissue, head muscle, stomach, intestine, heart, hemolymph, pleopods, ovaries and tail muscle, but not in eyestalks or the hepatopancreas of experimentally infected adult prawns. The presence of these viruses in ovarian tissue indicates the possibility of vertical transmission. Pleopods have been found to be a suitable organ for detecting these viruses in brooders using the RT-PCR technique. PMID:15672874

Sahul Hameed, A S; Yoganandhan, K; Sri Widada, J; Bonami, J R

2004-12-13

7

Detection and phylogenetic profiling of nodavirus associated with white tail disease in Malaysian Macrobrachium rosenbergii de Man.  

PubMed

White tail disease (WTD) is a serious viral disease in the hatcheries and nursery ponds of Macrobrachium rosenbergii in many parts of the world. A new disease similar to WTD was observed in larvae and post larvae of M. rosenbergii cultured in Malaysia. In the present study, RT-PCR assay was used to detect the causative agents of WTD, M. rosenbergii nodavirus (MrNV) and extra small virus (XSV) using specific primers for MrNV RNA2 and XSV. The results showed the presence of MrNV in the samples with or without signs of WTD. However, XSV was only detected in some of the MrNV-positive samples. Phylogenetic analysis showed that the RNA2 of our Malaysian isolates were significantly different from the other isolates. Histopathological studies revealed myofiber degeneration of the tail muscles and liquefactive myopathy in the infected prawns. This was the first report on the occurrence of MrNV in the Malaysian freshwater prawn. PMID:22223294

Saedi, Tayebeh Azam; Moeini, Hassan; Tan, Wen Siang; Yusoff, Khatijah; Daud, Hassan Mohd; Chu, Kua Beng; Tan, Soon Guan; Bhassu, Subha

2012-05-01

8

In vitro replication of Macrobrachium rosenbergii nodavirus and extra small virus in C6/36 mosquito cell line.  

PubMed

White tail disease (WTD) is a serious problem in hatcheries and nursery ponds of Macrobrachium rosenbergii in India and many parts of the world. The pathogenic agents have been identified as M. rosenbergii nodavirus (MrNV) associated with extra small virus (XSV), which is 27nm and 15nm in diameter, respectively. Replication of MrNV and XSV was investigated in apparently healthy C6/36 subclone of Aedes albopictus cell line. The results revealed that C6/36 cells were susceptible to these viruses. The replication of these viruses in C6/36 cells was confirmed by RT-PCR, acridine orange staining, infectivity study and electron microscopy. Cytoplasmic ribonucleic acid (RNA) stained by acridine orange increased by 48h, and by 72h larger proportion of cells which indicated alterations in quantity and localization of RNA in the infected cells. Post-larvae, challenged by immersion method using inoculum prepared from infected cells, exhibited lethargy, anorexia and opaqueness of abdominal muscle and 100% mortality was observed at 6 days post-infection. Experimentally infected C6/36 cells and post-larvae showed positive by RT-PCR, whereas control cells and healthy post-larvae showed negative. This is the first study to report the multiplication of MrNV and XSV in C6/36 cell line. PMID:17651820

Sudhakaran, R; Parameswaran, V; Sahul Hameed, A S

2007-12-01

9

[Rapid detection of Macrobrachium rosenbergii nodavirus isolated in China by a reverse-transcription loop-mediated isothermal amplification assay combined with a lateral flow dipstick method].  

PubMed

White coloration of the muscle of the giant river prawn (Macrobrachium rosenbergii) is a serious problem in China. The Macrobrachium rosenbergii Nodavirus (MrNV) has been confirmed to be the pathogen that causes this disorder. To develop a rapid, sensitive and specific technology for the detection of Macrobrachium rosenbergii Nodavirus isolated from China (MrNV-China), a reverse-transcription loop- mediated isothermal amplification assay combined with a lateral flow dipstick (RT-LAMP-LFD) assay method is described. A set of four primers and a labeled probe were designed specifically to recognize six distinct regions of the MrNV RNA2 gene. Results showed the sensitivity of the RT-LAMP-LFD assay was ten-times higher than the reverse-transcription loop-mediated isothermal amplification assay (RT-LAMP) with agarose gel electrophoresis. The assay was conducted with one-step amplification at 61°C in a single tube within 45 min. No product was generated from shrimps infected with other viruses, including DNA viruses (infectious hypodermal and hematopoietic necrosis virus (IHHNV); white spot syndrome virus (WSSV)) and RNA viruses (Taura syndrome virus (TSV); infectious myonecrosis virus (IMNV); yellow head virus (YHV)). Results were visualized by the LFD method. Therefore, the described rapid and sensitive assay is potentially useful for MrNV detection. PMID:25562958

Lin, Feng; Liu, Li; Hao, Gui-Jie; Cao, Zheng; Sheng, Peng-Cheng; Wu, Ying-Lei; Shen, Jin-Yu

2014-09-01

10

Extra small virus-like particles (XSV) and nodavirus associated with whitish muscle disease in the giant freshwater prawn, Macrobrachium rosenbergii.  

PubMed

A disease of Macrobrachium rosenbergii, the giant freshwater prawn, farmed in China was recently recorded in Zhejiang, Jiangsu, Shanghai, Guangxi and Guangdong provinces. The clinical sign of the disease, which develops in post-larvae (PL), is a whitish appearance of the muscles, particularly noticeable in the abdomen. Mortalities may reach 100% in some hatcheries. Investigations by transmission electron microscopy after negative staining of diseased PL homogenates showed the presence of two types of viral particles: one, unenveloped, icosahedral in shape, 26-27 nm in diameter, the second, much smaller, about 14-16 nm in diameter, designated extra small virus particle (XSV). The large virus has a genome with two pieces of ssRNA (RNA-1 and RNA-2), of 3 and 1.2 kb, respectively. Hybridization tests confirmed that this large virus is closely related to M. rosenbergii nodavirus (MrNV) which was isolated from diseased prawns in a hatchery in the French West Indies. Its very small size and hypothesized biochemical and biological characteristics suggest XSV is a new type of crustacean virus. As XSV has always been found associated with the larger virus (nodavirus) and is located in muscle and connective cells of diseased animals, it could be an autonomous virus, a helper-type virus or a satellite-like virus. PMID:14575370

Qian, D; Shi, Z; Zhang, S; Cao, Z; Liu, W; Li, L; Xie, Y; Cambournac, I; Bonami, J-R

2003-09-01

11

Production of recombinant capsid protein of Macrobrachium rosenbergii nodavirus (r-MCP43) of giant freshwater prawn, M. rosenbergii (de Man) for immunological diagnostic methods.  

PubMed

White tail disease (WTD) caused by Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus (XSV) is a serious problem in prawn hatcheries. The gene for capsid protein of MrNV (MCP43) was cloned into pRSET B expression vector. The MCP43 protein was expressed as a protein with a 6-histidine tag in Escherichia coli GJ1158 with NaCl induction. This recombinant protein, which was used to raise the antiserum in rabbits, recognized capsid protein in different WTD-infected post-larvae and adult prawn. Various immunological methods such as Western blot, dot blot and ELISA techniques were employed to detect MrNV in infected samples using the antiserum raised against recombinant MCP43 of MrNV. The dot blot assay using anti-rMCP43 was found to be capable of detecting MrNV in WTD-infected post-larvae as early as at 24 h post-infection. The antiserum raised against r-MCP43 could detect the MrNV in the infected samples at the level of 100 pg of total protein. The capsid protein of MrNV estimated by ELISA using anti-rMCP43 and pure r-MCP43 as a standard was found to increase gradually during the course of infection from 24 h p.i. to moribund stage. The results of immunological diagnostic methods employed in this study were compared with that of RT-PCR to test the efficiency of antiserum raised against r-MCP43 for the detection of MrNV. The Western blot, dot blot and ELISA detected all MrNV-positive coded samples as detected by RT-PCR. PMID:23952017

Farook, M A; Madan, N; Taju, G; Majeed, S Abdul; Nambi, K S N; Raj, N Sundar; Vimal, S; Hameed, A S Sahul

2014-08-01

12

Simultaneous detection of Macrobrachium rosenbergii nodavirus and extra small virus by a single tube, one-step multiplex RT-PCR assay.  

PubMed

Post-larvae of Macrobrachium rosenbergii infected with white tail disease were collected from hatcheries and nursery ponds in India. The causative organisms have been identified as Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus (XSV). A one-step multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) has been developed to detect these viruses simultaneously in naturally and experimentally infected prawns. Several parameters were assayed in order to optimize the protocol for simultaneous detection. Naturally and experimentally infected prawns showed two prominent bands of 681 and 500 bp for MrNV and XSV, respectively, as in separate RT-PCR assays. Experimentally infected adult prawns showed two bands for these two viruses in all the organs, except hepatopancreas and eyestalk, as seen in normal RT-PCR. The sensitivity test carried out on the primer sets of MrNV and XSV revealed that these primers could simultaneously detect the two viruses at a level of 25 fg of total RNA prepared from infected samples using this multiplex RT-PCR protocol. PMID:15705151

Yoganandhan, K; Sri Widada, J; Bonami, J R; Sahul Hameed, A S

2005-02-01

13

White Tail Disease of Freshwater Prawn, Macrobrachium rosenbergii.  

PubMed

Macrobrachium rosenbergii is the most important cultured freshwater prawn in the world and it is now farmed on a large scale in many countries. Generally, freshwater prawn is considered to be tolerant to diseases but a disease of viral origin is responsible for severe mortalities in larval, post-larval and juvenile stages of prawn. This viral infection namely white tail disease (WTD) was reported in the island of Guadeloupe in 1995 and later in Martinique (FrenchWest Indies) in Taiwan, the People's Republic of China, India, Thailand, Australia and Malaysia. Two viruses, Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus-like particle (XSV) have been identified as causative agents of WTD. MrNV is a small icosahedral non-enveloped particle, 26-27 nm in diameter, identified in the cytoplasm of connective cells. XSV is also an icosahedral virus and 15 nm in diameter. Clinical signs observed in the infected animals include lethargy, opaqueness of the abdominal muscle, degeneration of the telson and uropods, and up to 100 % within 4 days. The available diagnostic methods to detect WTD include RT-PCR, dot-blot hybridization, in situ hybridization and ELISA. In experimental infection, these viruses caused 100 % mortality in post-larvae but failed to cause mortality in adult prawns. The reported hosts for these viruses include marine shrimp, Artemia and aquatic insects. Experiments were carried out to determine the possibility of vertical transmission of MrNV and XSV in M. rosenbergii. The results indicate that WTD may be transferred from infected brooders to their offspring during spawning. Replication of MrNV and XSV was investigated in apparently healthy C6/36 Aedes albopictus and SSN-1 cell lines. The results revealed that C6/36 and SSN-1cells were susceptible to these viruses. No work has been carried out on control and prevention of WTD and dsRNA against protein B2 produced RNAi that was able to functionally prevent and reduce mortality in WTD-infected redclaw crayfish. PMID:23997437

Sahul Hameed, A S; Bonami, Jean-Robert

2012-09-01

14

Production and Application of Polyclonal Antibodies Against Recombinant Capsid Protein of Extra Small Virus of Macrobrachium rosenbergii.  

PubMed

Macrobrachium rosenbergii nodavirus along with a satellite virus, extra small virus (XSV) causes white tail disease (WTD) in the giant freshwater prawn M. rosenbergii. Infected M. rosenbergii postlarvae were collected from a hatchery in Kakinada, Andhra Pradesh. The gene coding the capsid protein of XSV was cloned in a bacterial expression vector pRSET A and the recombinant protein was expressed in Escherichia coli BL21(DE3)pLysS cells. The recombinant protein was purified by Nickel affinity chromatography. Polyclonal antibodies were produced in mice against the recombinant protein and the antibodies reacted specifically with the recombinant protein and XSV in WTD-infected tissues. This is the first report of detection of XSV using antibodies against recombinant capsid protein. PMID:24293828

Neethi, V; Sivakumar, N; Kumar, Kundan; Rajendran, K V; Makesh, M

2012-12-01

15

White tail disease of the giant freshwater prawn Macrobrachium rosenbergii in Thailand.  

PubMed

White tail disease (WTD) of the freshwater prawn Macrobrachium rosenbergii has recently been the cause of high mortalities in Thai prawn farms. The causative agents of this disease in other countries are M. rosenbergii nodavirus (MrNV) and extra small virus (XSV), which are usually detected using reverse transcriptase-polymerase chain reaction (RT-PCR) protocols. Using RT-PCR, most Thai post-larvae (PL) samples showing gross signs of WTD tested positive for MrNV but only a few were positive for XSV. In contrast, all tested brooder samples were positive for both MrNV and XSV. The possibility that brooders infected with MrNV and XSV could transmit the viruses to larvae and PL should be examined. Cloning, sequencing and comparison of deduced amino acid sequences of RT-PCR amplicons of WTD samples from Thailand with those of MrNV and XSV previously reported from the French West Indies and China revealed that the MrNV were closely related but not identical while those from XSV were identical. This is the first report of MrNV and XSV from Thailand. PMID:16724570

Yoganandhan, Kalidoss; Leartvibhas, Manee; Sriwongpuk, Supamas; Limsuwan, Chalor

2006-04-01

16

Quantitative relationship of two viruses (MrNV and XSV) in white-tail disease of Macrobrachium rosenbergii.  

PubMed

Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus (XSV) were purified from diseased freshwater prawns M. rosenbergii and used to infect healthy post-larvae (PL) by an immersion method. Three groups of prawns were challenged with various combined doses of MrNV and XSV. Signs of white-tail disease (WTD) were observed in Groups 1 and 2, which had been challenged with combinations containing relatively high proportions of MrNV and low proportions of XSV. By contrast there was little sign of WTD in Group 3, which had been challenged with a higher proportion of XSV than MrNV. A 2-step Taqman real-time RT-PCR was developed and applied to quantify viral copy numbers in each challenged PL. Results showed that genomic copies of both viruses were much higher in Groups 1 and 2 than they were in Group 3, indicating that MrNV plays a key role in WTD of M. rosenbergii. The linear correlation between MrNV and XSV genome copies in infected prawns demonstrated that XSV is a satellite virus, dependent on MrNV, but its role in pathogenicity of WTD remains unclear. PMID:16921996

Zhang, Huajun; Wang, Jianmin; Yuan, Junfa; Li, Lijuan; Zhang, Jianhong; Bonami, Jean-Robert; Shi, Zhengli

2006-07-11

17

RT-PCR amplification and sequence analysis of extra small virus associated with white tail disease of Macrobrachium rosenbergii (de Man) cultured in Taiwan.  

PubMed

Post-larvae of Macrobrachium rosenbergii infected with white tail disease (WTD) have been reported in Taiwan. The causative agents have been identified as M. rosenbergii nodavirus (MrNV) associated with extra small virus (XSV). The present study is the first report confirming the presence of XSV virus in M. rosenbergii displaying WTD symptoms in Taiwan by reverse transcription polymerase chain reaction (RT-PCR). A 772 bp amplified product was obtained by RT-PCR, cloned and sequenced. The nucleotide sequence analysis of the 772 bp DNA fragment revealed 98% and 97% identity with XSV isolated from China and India, respectively. Comparison of the deduced amino acid sequences of the XSV partial genome showed strong homology (99% and 97%) with isolates from China and India. Phylogenetic analysis revealed the XSV-Taiwan isolate was more closely related to the Chinese rather than the Indian isolates. The results demonstrated the presence of XSV virus co-infection in M. rosenbergii cultured in Taiwan suffering from WTD. PMID:17352787

Wang, C S; Chang, J S; Shih, H H; Chen, S N

2007-03-01

18

Feasibility of direct utilization of selected geothermal water for aquaculture of macrobrachium rosenbergii. Technical report  

SciTech Connect

The feasibility was tested of direct utilization of geothermal water for the aquaculture of Malaysian freshwater prawns (Macrobrachium rosenbergii). A problem with using geothermal water for aquaculture is the chemical composition of the water with high flouride levels being a particular problem. Results show that (1) some geothermal water in Idaho can be used directly for the aquaculture of Macrobrachium rosenbergii, (2) high flouride levels cannot be directly correlated with high mortality rates and (3) low flouride levels do not correlate with high growth rates.

Spinosa, C.

1984-05-01

19

Routine Metabolic Rate and Limiting Oxygen Concentration of Freshwater Prawn Macrobrachium rosenbergii Larvae  

Technology Transfer Automated Retrieval System (TEKTRAN)

Malaysian prawns, Macrobrachium rosenbergii, are hatched and raised indoors in small tanks. Prawns may be raised and shipped at high densities which could result in low dissolved oxygen (DO) conditions. Because DO may play an important role in prawn development and survival, we measured routine me...

20

Changes of Myofibrillar Proteins and Texture in Freshwater Prawn, Macrobrachium rosenbergii, During Iced Storage  

E-print Network

of mushiness has been demon strated (Nip and Moy, 1988). Proteolysis of muscle proteins by proteolytic and/shrimp protein compo nents have been very limited. Wong (1982) studied the microstructural changes in musclesChanges of Myofibrillar Proteins and Texture in Freshwater Prawn, Macrobrachium rosenbergii

21

Grooming as a secondary behavior in the shrimp Macrobrachium rosenbergii (Crustacea, Decapoda, Caridea)  

PubMed Central

Abstract The giant freshwater prawn, Macrobrachium rosenbergii, is a large shrimp extensively used in aquaculture whose grooming behaviors were analyzed in this study. Macrobrachium rosenbergii exhibits three unique male morphotypes that differ in their behavior, morphology and physiology: small-clawed males (SM), orange-clawed males (OC) and blue-clawed males (BC). The largest and most dominant males, BC males, are predicted to have significantly different grooming behaviors compared to females and the other two male morphotypes. These BC males may be too large and bulky to efficiently groom and may dedicate more time to mating and agonistic interactions than grooming behaviors. Observations were conducted to look at the prevalence of grooming behaviors in the absence and presence of conspecifics and to determine if any differences in grooming behavior exist among the sexes and male morphotypes. Significant differences in the grooming behaviors of all individuals (females and male morphotypes) were found. BC males tended to have the highest grooming time budget (percent of time spent grooming) while SM males had a relatively low grooming time budget. The grooming behaviors of the male morphotypes differed, indicating while these males play distinct, separate roles in the social hierarchy, they also have different grooming priorities. The conditions in which Macrobrachium rosenbergii are cultured may result in increased body fouling, which may vary, depending on the grooming efficiencies and priorities of these male morphotypes. Overall, grooming behaviors were found to be a secondary behavior which only occurred when primary behaviors such as mating, feeding or fighting were not present. PMID:25561831

VanMaurik, Lauren N.; Wortham, Jennifer L.

2014-01-01

22

[Influence of lecithotrofic feeding on growth and development of larvae of freshwater shrimp Macrobrachium rosenbergii].  

PubMed

In the giant freshwater shrimp Macrobrachium rosenbergii (De Man), lecithotrofic feeding was discovered at the zoea I stage, and facultative lecithotrofic feeding was found at the zoea II stage. Cases of the completion of the first two stages without feeding were detected. However, a delay in feeding at the zoea II stage caused the inhibition of the growth and development of larvae. In this connection, we recommend to introduce food to the aquaculture of the giant freshwater shrimp on the end of the first day after hatching, when the first zoea II larvae emerge. PMID:21786650

Borisov, R R; Kriakhova, N V

2011-01-01

23

Serological characterization of humoral lectins from the freshwater prawn Macrobrachium rosenbergii.  

PubMed

We have detected and partially characterized multiple lectins present in the serum of the freshwater prawn Macrobrachium rosenbergii. Since agglutination of erythrocytes (RBC) is not abolished by treatment with Vibrio cholerae neuraminidase (VCN), Macrobrachium shows an agglutination pattern different from that of other sialic acid-specific lectins such as Limulus polyphemus lectin. However, after absorption with primate and bird VCN-treated RBC, Macrobrachium serum exhibits high titers with untreated and pronase-treated RBC and no agglutination of VCN-treated RBC, suggesting a typical sialic acid specific lectin agglutination profile. Hemagglutination-inhibition tests indicate that sialic acid containing compounds are the best inhibitors for Macrobrachium lectins. Subterminal sugars and type of linkage are probably important for the lectin binding since bovine submaxillary mucin (containing mainly terminal NANA-alpha-2 6-GalNAc-) is a better inhibitor than fetuin (containing mainly terminal NANA-alpha-2 leads to 3-Gal-) and colominic acid (-NANA-alpha-2 leads to 8-NANA-) is a weak inhibitor. PMID:6840378

Vasta, G R; Warr, G W; Marchalonis, J J

1983-01-01

24

Potential use of the Macrobrachium rosenbergii lectin for diagnosis of T-cell acute lymphoblastic leukemia.  

PubMed

T-cell acute lymphoblastic leukemia is the most common form of cancer in children. Lectins are proteins or glycoproteins from plants or animals that recognize oligossacharides on the cell surface and have been used to characterize the structural changes of oligosaccharides in leukemias. In this study, we used the lectin from the freshwater prawn Macrobrachium (M. rosenbergii), specific for acetyl groups in sialylated glycans, because increased sialylation of glycoproteins and glycolipids has been identified in lymphoblastic leukemias. We compared the specificity of the M. rosenbergii lectin for lymphoblastic leukemias with the specificities of the lectins from Triticum vulgaris, Solanum tuberosum, Arachis hipogaea, and Phytolacca americana. By morphologic and phenotype characterization with a panel of monoclonal antibodies, we identified four types of leukemias from 106 leukemia patients: 11 cases of T-cell acute lymphoblastic leukemia, 61 cases of B-cell acute lymphoblastic leukemia, 24 cases of acute myeloblastic leukemia, and 10 cases of acute biphenotypic leukemia. As determined by cytofluorometric assays, nine of the eleven cases with T-cell acute lymphoblastic leukemia (8 +/- 3 years old) were specifically identified with the lectin from M. rosenbergii. In contrast, only six cases of B-cell leukemia, one case of myeloblastic leukemia, and 2 cases of biphenotypic leukemia were identified with this M. rosenbergii lectin. The other lectins tested showed no capacity to differentiate, in a significant manner, any of the four types of leukemias tested. Thus, the lectin from M. rosenbergii could be considered a useful tool for the diagnosis and study of T-cell acute lymphoblastic leukemia. PMID:18212483

Pérez-Campos-Mayoral, Laura; Ruiz-Argüelles, Alejandro; Pérez-Romano, Beatriz; Zenteno, Edgar; Hernández-Cruz, Pedro; Martínez-Cruz, Ruth; Martínez-Cruz, Margarito; Pina-Canseco, Socorro; Pérez-Campos, Eduardo

2008-01-01

25

TBT Effects on the Development of Intersex (Ovotestis) in Female Fresh Water Prawn Macrobrachium rosenbergii  

PubMed Central

The impact of tributyltin (TBT) on the female gonad and the endocrine system in Macrobrachium rosenbergii was studied. Prawns were exposed to environmentally realistic concentrations of 10, 100, and 1000?ng/L of TBT for 6 months. Dose dependent effects were noticed in TBT exposed prawns. At 1000?ng/L TBT caused ovotestis formation (formation of male germ cells in ovary). Presence immature oocytes, fusion of developing oocytes, increase in interstitial connective tissues, and its modification into tubular like structure and abundance of spermatogonia in the ovary of TBT treated prawns. The control prawn ovary showed normal architecture of cellular organelles such as mature oocytes with type 2 yolk globules, lipid droplets, normal appearance of yolk envelop, and uniformly arranged microvilli. On the other hand, type 1 yolk globules, reduced size of microvilli, spermatogonial cells in ovary, spermatogonia with centrally located nucleus, and chromatin distribution throughout the nucleoplasm were present in the TBT treated group. Immunofluorescence staining indicated a reduction in vitellin content in ovary of TBT treated prawn. Moreover, TBT had inhibited the vitellogenesis by causing hormonal imbalance in M. rosenbergii. Thus, the present investigation demonstrates that TBT substantially affects sexual differentiation and gonadal development in M. rosenbergii. PMID:25121096

Peranandam, Revathi; Palanisamy, Iyapparaj; Lourdaraj, Arockia Vasanthi; Natesan, Munuswamy; Vimalananthan, Arun Prasanna; Thangaiyan, Suganya; Perumal, Anantharaman; Muthukalingan, Krishnan

2014-01-01

26

Laboratory toxicity test and post-exposure feeding inhibition using the giant freshwater prawn Macrobrachium rosenbergii.  

PubMed

A bioassay was developed using post-larvae of freshwater prawn Macrobrachium rosenbergii (length 9-10 mm) in order to determine the toxicity of profenofos, dimethoate, chlorpyrifos, carbendazim and zinc. This was the first study in the tropics with M. rosenbergii, particularly at the post-larvae stage (9-10 mm) on lethal (LC(50)) and sublethal (EC(50)) effects of toxic substances using post-exposure feeding rate as end point. Median lethal concentrations (LC(50) at 24 and 48 h) were respectively estimated as 11.6 and 9.8 microg L(-1) for profenofos, 142.1 and 102.7 microg L(-1) for dimethoate, 0.7 and 0.3 microg L(-1) for chlorpyrifos, and 439.7 and 329 microg L(-1) for zinc. Effects of carbendazim could not be estimated because carbendazim exposure needs more than 24h exposure period to produce observable effects at the concentrations used. The EC(50) using post-exposure feeding rates determined for profenofos, dimethoate, chlorpyrifos and zinc were 6.023, 269.3, 0.293 and 109.01 microg L(-1), respectively, at 24 h of exposure. Only chlorpyrifos and zinc had LC(50) concentrations greater than the post-exposure feeding EC(50) concentrations. This study demonstrated that the M. rosenbergii could also be used as a test animal to detect the effects of different chemical contaminants in aquatic environments. PMID:19103457

Satapornvanit, Kriengkrai; Baird, D J; Little, D C

2009-03-01

27

Identification and function of 11 Rab GTPases in giant freshwater prawn Macrobrachium rosenbergii.  

PubMed

Rab GTPases, members of the Ras-like GTPase superfamily, are central elements in endocytic membrane trafficking. However, little is known of the Rab genes in the giant freshwater prawn Macrobrachium rosenbergii. In this study, 11 Rab genes were identified from M. rosenbergii. All MrRabs have a RAB domain. Phylogenetic analysis showed that these 11 MrRabs were divided into different groups. The MrRab genes were ubiquitously expressed in heart, hemocytes, hepatopancreas, gills, stomach, and intestines. Real-time polymerase chain reaction revealed that the MrRab genes were significantly upregulated by white spot syndrome virus (WSSV) in the prawns, indicating that MrRabs might play an important role in innate immune response against WSSV. Moreover, after challenge with Vibrio parahaemolyticus, the expression levels of all MrRabs in the hepatopancreas were also upregulated, which might indicated the involvement of MrRabs in prawns antibacterial immunity. In all, these preliminary results showed that MrRabs were involved in innate immunity of M. rosenbergii. PMID:25542378

Huang, Ying; Ren, Qian

2015-03-01

28

Investigation into the possible natural occurence of semicarbazide in Macrobrachium rosenbergii prawns.  

PubMed

In the past year there has been an increased incidence in Belgium of cases of positive semicarbazide (SEM) tests in imported freshwater Macrobrachium rosenbergii prawns, seemingly indicating the possible abuse of nitrofurazone, a banned antimicrobial agent. This was in contrast to all other European countries where no significant increase in SEM-positive samples was detected. A possible explanation for this discrepancy between Belgium and the other European Union member states could be the fact that only in Belgium were whole prawns (meat + shell) analyzed for the presence of tissue-bound metabolites of nitrofurans, whereas in the other countries only the edible part (meat) of these prawns was analyzed. To investigate the possible natural occurrence of SEM in freshwater prawns, an animal trial was set up. In this experiment two groups of 10 juvenile M. rosenbergii, previously raised under standardized laboratory conditions, were stocked into two separate aquaria, a control group under reference conditions (no addition of nitrofurazone) and a group exposed to a daily dose of 50 mg of nitrofurazone L(-1) of culture water. Results of this animal trial proved that SEM naturally occurs in M. rosenbergii prawns but that at the current minimum required performance limit (MRPL) no tissue-bound SEM can be found in the meat of nontreated animals. In addition to this animal trial, commercial samples of other crustacean species, the shell and meat of which were analyzed separately, were also analyzed for the presence of SEM. PMID:21299238

Van Poucke, Christof; Detavernier, Christ'l; Wille, Mathieu; Kwakman, Jan; Sorgeloos, Patrick; Van Peteghem, Carlos

2011-03-01

29

Monodon baculovirus (MBV) infects the freshwater prawn Macrobrachium rosenbergii cultivated in Thailand.  

PubMed

Field specimens of post-larvae of the giant freshwater prawn (Macrobrachium rosenbergii) from Thailand showed hepatopancreatic tubule epithelial cells that contained central, eosinophilic inclusions within enlarged nuclei and marginated chromatin. These inclusions resembled those produced by some baculoviruses prior to formation of occlusion bodies that enclose virions in a polyhedrin protein matrix. By electron microscopy, the intranuclear inclusions contained bacilliform, enveloped virions (approximately 327+/-29nmx87+/-12nm) with evenly dense, linear nucleocapsids surrounded by trilaminar envelopes with lateral pockets containing nucleoproteinic filaments. In some cases, these were accompanied by moderately electron dense, spherical particles of approximately 20nm diameter resembling polyhedrin subunits of occlusion bodies (OB) of a bacilliform virus of the black tiger shrimp Penaeus monodon, previously reported from Thailand and called monodon baculovirus (MBV). It is currently listed by the International Committee on Taxonomy of viruses as Penaeus monodon nucleopolyhedrovirus (PemoNPV). Two polymerase chain reaction (PCR) assays for MBV gave positive results with DNA extracts prepared from M. rosenbergii samples using the hot phenol technique. One of these assays targeted the polyhedrin gene of MBV to which the resulting amplicon showed 100% sequence identity. Presence of the Penaeus monodon virus polyhedrin gene was confirmed by in situ hybridization assays and by positive immunohistochemical reactions in one sample batch. The data revealed that MBV can be found but may rarely produce polyhedrin occlusion bodies in M. rosenbergii. PMID:19963025

Gangnonngiw, Warachin; Laisutisan, Kesinee; Sriurairatana, Siriporn; Senapin, Saengchan; Chuchird, Niti; Limsuwan, Chalor; Chaivisuthangkura, Parin; Flegel, Timothy W

2010-03-01

30

First report on vertical transmission of a plasmid DNA in freshwater prawn, Macrobrachium rosenbergii.  

PubMed

Outbreak of WSSV disease is one of the major stumbling blocks in shrimp aquaculture. DNA vaccines have shown potential for mass scale vaccination owing to their stability, cost effectiveness and easy maintenance. Development of economically feasible delivery strategies remains to be a major challenge. This study demonstrates vertical transmission of a plasmid DNA in a decapod Macrobrachium rosenbergii for the first time. Females at three different maturation stages (immature, matured and berried) and mature males were injected with a plasmid DNA and allowed to spawn with untreated counterparts. Using specific primers the plasmid DNA could be amplified from the offspring of all groups except that of berried females. For this confirmation genomic DNA was isolated from 3 pools of 10 post larvae in each group. This presents an ideal strategy to protect young ones at zero stress. PMID:24933022

Chowdhury, Labrechai Mog; Gireesh-Babu, P; Pavan-Kumar, A; Suresh Babu, P P; Chaudhari, Aparna

2014-09-01

31

Prophenoloxidase activating enzyme-III from giant freshwater prawn Macrobrachium rosenbergii : characterization, expression and specific enzyme activity  

Microsoft Academic Search

The prophenoloxidase activating system is an important innate immune response against microbial infections in invertebrates.\\u000a The major enzyme, phenoloxidase, is synthesized as an inactive precursor and its activation to an active enzyme is mediated\\u000a by a cascade of clip domain serine proteinases. In this study, a cDNA encoding a prophenoloxidase activating enzyme-III from\\u000a the giant freshwater prawn Macrobrachium rosenbergii, designated

Jesu Arockiaraj; Sarasvathi Easwvaran; Puganeshwaran Vanaraja; Arun Singh; Rofina Yasmin Othman; Subha Bhassu

32

Toxicity of phenol on Macrobrachium rosenbergii (de Man) eggs, larvae, and post-larvae  

SciTech Connect

Literature on the toxicities of phenol on aquatic organisms is very limited. USEPA reported that the acute and chronic toxicities of phenol to freshwater aquatic life occur at concentrations as low as 10.2 mg/L and 2.56 mg/L, respectively. While for the saltwater aquatic life the acute toxicity occurs at concentrations as low as 5.8 mg/L. No data are available for the chronic toxicity of phenol to saltwater aquatic life. Sublethal concentrations of phenol have significant effects on the physiological and histological processes of the aquatic organisms: such as gill necrosis; destruction of erythrocyte cells; inhibition of sexual activities; suppression on growth and reduction of resistance to diseases. Macrobrachium rosenbergii(de Man) is the sole freshwater prawn cultured in Malaysia. Occasionally, the hatcheries are unable to produce the post-larvae because of undefined pollutants present in the water supplies. It has been observed that the use of cracked fiberglass tanks for larvae rearing is correlated with high mortality. This high mortality is probably due to the toxicity of the phenolic compounds which are leached out from the fiber glass tank into the water. This study was undertaken to evaluate the toxicity of phenol on eggs, larvae and post-larvae of M. rosenbergii and to set the water quality criteria of phenol for the said species. 16 refs., 3 tabs.

Law, A.T.; Yeo, M.E. [Universiti Kolej Terengganu (UPM), Darul Iman (Malaysia)] [Universiti Kolej Terengganu (UPM), Darul Iman (Malaysia)

1997-03-01

33

A cytosolic glutathione s-transferase, GST-theta from freshwater prawn Macrobrachium rosenbergii: molecular and biochemical properties.  

PubMed

Glutathione S-transferases play an important role in cellular detoxification and may have evolved to protect cells against reactive oxygen metabolites. In this study, we report the molecular characterization of glutathione s-transferase-theta (GST-?) from freshwater prawn Macrobrachium rosenbergii. A full length cDNA of GSTT (1417 base pairs) was isolated and characterized bioinformatically. Exposure to virus (white spot syndrome baculovirus or M. rosenbergii nodovirus), bacteria (Aeromonas hydrophila or Vibrio harveyi) or heavy metals (cadmium or lead) significantly increased the expression of GSTT (P<0.05) in hepatopancreas. Recombinant GST-? with monochlorobimane substrate had an optimum activity at pH7.5 and 35 °C. Furthermore recombinant GST-? activity was abolished by the denaturants triton X-100, Gua-HCl, Gua-thiocyanate, SDS and urea in a dose-dependent manner. Overall, the results suggest a potential role for M. rosenbergii GST-? in detoxification and possibly conferring immune protection. PMID:24879918

Arockiaraj, Jesu; Gnanam, Annie J; Palanisamy, Rajesh; Bhatt, Prasanth; Kumaresan, Venkatesh; Chaurasia, Mukesh Kumar; Pasupuleti, Mukesh; Ramaswamy, Harikrishnan; Arasu, Abirami; Sathyamoorthi, Akila

2014-08-10

34

Susceptibility of juvenile Macrobrachium rosenbergii to different doses of high and low virulence strains of white spot syndrome virus (WSSV).  

PubMed

As some literature on the susceptibility of different life stages of Macrobrachium rosenbergii to white spot syndrome virus (WSSV) is conflicting, the pathogenesis, infectivity and pathogenicity of 2 WSSV strains (Thai-1 and Viet) were investigated here in juveniles using conditions standardized for Penaeus vannamei. As with P. vannamei, juvenile M. rosenbergii (2 to 5 g) injected with a low dose of WSSV-Thai-1 or a high dose of WSSV-Viet developed comparable clinical pathology and numbers of infected cells within 1 to 2 d post-infection. In contrast, a low dose of WSSV-Viet capable of causing mortality in P. vannamei resulted in no detectable infection in M. rosenbergii. Mean prawn infectious dose 50% endpoints (PID?? ml?¹) determined in M. rosenbergii were in the order of 100-fold higher for WSSV-Thai-1 (105.3 ± 0.4 PID?? ml?¹) than for WSSV-Viet (103.2 ± 0.2 PID?? ml?¹), with each of these being about 20-fold and 400-fold lower, respectively, than found previously in P. vannamei. The median lethal dose (LD?? ml?¹) determined in M. rosenbergii was also far higher (~1000-fold) for WSSV-Thai-1 (105.4 ± 0.4 LD?? ml?¹) than for WSSV-Viet (102.3 ± 0.3 LD?? ml?¹). Based on these data, it is clear that juvenile M. rosenbergii are susceptible to WSSV infection, disease and mortality. In comparison to P. vannamei, however, juvenile M. rosenbergii appear more capable of resisting infection and disease, particularly in the case of a WSSV strain with lower apparent virulence. PMID:22968789

Corteel, Mathias; Dantas-Lima, João J; Tuan, Vo Van; Thuong, Khuong Van; Wille, Mathieu; Alday-Sanz, Victoria; Pensaert, Maurice B; Sorgeloos, Patrick; Nauwynck, Hans J

2012-09-12

35

Transcriptomics of a Giant Freshwater Prawn (Macrobrachium rosenbergii): De Novo Assembly, Annotation and Marker Discovery  

PubMed Central

Background Giant freshwater prawn (Macrobrachium rosenbergii or GFP), is the most economically important freshwater crustacean species. However, as little is known about its genome, 454 pyrosequencing of cDNA was undertaken to characterise its transcriptome and identify genes important for growth. Methodology and Principal Findings A collection of 787,731 sequence reads (244.37 Mb) obtained from 454 pyrosequencing analysis of cDNA prepared from muscle, ovary and testis tissues taken from 18 adult prawns was assembled into 123,534 expressed sequence tags (ESTs). Of these, 46% of the 8,411 contigs and 19% of 115,123 singletons possessed high similarity to sequences in the GenBank non-redundant database, with most significant (E value < 1e–5) contig (80%) and singleton (84%) matches occurring with crustacean and insect sequences. KEGG analysis of the contig open reading frames identified putative members of several biological pathways potentially important for growth. The top InterProScan domains detected included RNA recognition motifs, serine/threonine-protein kinase-like domains, actin-like families, and zinc finger domains. Transcripts derived from genes such as actin, myosin heavy and light chain, tropomyosin and troponin with fundamental roles in muscle development and construction were abundant. Amongst the contigs, 834 single nucleotide polymorphisms, 1198 indels and 658 simple sequence repeats motifs were also identified. Conclusions The M. rosenbergii transcriptome data reported here should provide an invaluable resource for improving our understanding of this species' genome structure and biology. The data will also instruct future functional studies to manipulate or select for genes influencing growth that should find practical applications in aquaculture breeding programs. PMID:22174756

Jung, Hyungtaek; Lyons, Russell E.; Dinh, Hung; Hurwood, David A.; McWilliam, Sean; Mather, Peter B.

2011-01-01

36

Post-Embryonic Transcriptomes of the Prawn Macrobrachium rosenbergii: Multigenic Succession through Metamorphosis  

PubMed Central

Like many metazoans, the freshwater prawn Macrobrachium rosenbergii begins its post-embryonic life with a set of morphologically distinct planktonic larval stages, followed by a benthic post-larval stage during which the maturing organism differs from the larvae both ecologically and physiologically. Understanding of the molecular basis underlying morphogenesis in crustaceans is limited to the observation that methyl farnesoate, the non-epoxidated form of the insect juvenile hormone, acts as the active crustacean juvenoid. Molt steroids were also linked to morphogenesis and several other molecular pathways, such as Hedgehog and Wnt, are known to underlie morphogenesis in all metazoans examined and, as such, are thought to do the same in crustaceans. Using next generation sequencing, we deep-sequenced the transcriptomes of several larval and post-larval stages. De novo assembly, followed by bioinformatics analysis, revealed that many novel transcripts are over-expressed in either larvae- or post-larvae-stage prawn, shedding light on the molecular basis underlying M. rosenbergii metamorphosis. Fast larval molting rates and periodic morphological changes were reflected in over-expression of transcripts annotated to the cell cycle, DNA replication and morphogenic pathways (i.e., Hedgehog and Wnt). Further characterization of transcripts assigned to morphogenic pathways by real-time RT-PCR reconfirmed their over-expression in larvae, albeit with a more complex expression pattern when examined in the individual developmental stages. The expression level of an orthologue of cytochrome P450, 15A1, known to epoxidize methyl farnesoate in insects, was increased in the late larval and early post-larval stages, in accordance with the role of methyl farnesoate in crustacean metamorphosis. This study exemplifies the applicability of a high-throughput sequencing approach for studying complex traits, including metamorphosis, providing new insight into this unexplored area of crustacean research. PMID:23372848

Ventura, Tomer; Manor, Rivka; Aflalo, Eliahu D.; Chalifa-Caspi, Vered; Weil, Simy; Sharabi, Omri; Sagi, Amir

2013-01-01

37

Post-embryonic transcriptomes of the prawn Macrobrachium rosenbergii: multigenic succession through metamorphosis.  

PubMed

Like many metazoans, the freshwater prawn Macrobrachium rosenbergii begins its post-embryonic life with a set of morphologically distinct planktonic larval stages, followed by a benthic post-larval stage during which the maturing organism differs from the larvae both ecologically and physiologically. Understanding of the molecular basis underlying morphogenesis in crustaceans is limited to the observation that methyl farnesoate, the non-epoxidated form of the insect juvenile hormone, acts as the active crustacean juvenoid. Molt steroids were also linked to morphogenesis and several other molecular pathways, such as Hedgehog and Wnt, are known to underlie morphogenesis in all metazoans examined and, as such, are thought to do the same in crustaceans. Using next generation sequencing, we deep-sequenced the transcriptomes of several larval and post-larval stages. De novo assembly, followed by bioinformatics analysis, revealed that many novel transcripts are over-expressed in either larvae- or post-larvae-stage prawn, shedding light on the molecular basis underlying M. rosenbergii metamorphosis. Fast larval molting rates and periodic morphological changes were reflected in over-expression of transcripts annotated to the cell cycle, DNA replication and morphogenic pathways (i.e., Hedgehog and Wnt). Further characterization of transcripts assigned to morphogenic pathways by real-time RT-PCR reconfirmed their over-expression in larvae, albeit with a more complex expression pattern when examined in the individual developmental stages. The expression level of an orthologue of cytochrome P450, 15A1, known to epoxidize methyl farnesoate in insects, was increased in the late larval and early post-larval stages, in accordance with the role of methyl farnesoate in crustacean metamorphosis. This study exemplifies the applicability of a high-throughput sequencing approach for studying complex traits, including metamorphosis, providing new insight into this unexplored area of crustacean research. PMID:23372848

Ventura, Tomer; Manor, Rivka; Aflalo, Eliahu D; Chalifa-Caspi, Vered; Weil, Simy; Sharabi, Omri; Sagi, Amir

2013-01-01

38

Peroxinectin gene transcription of the giant freshwater prawn Macrobrachium rosenbergii under intrinsic, immunostimulant, and chemotherapeutant influences.  

PubMed

Peroxinectin (PE) gene expressions were determined using real-time PCR in the giant freshwater prawn Macrobrachium rosenbergii based on moulting; prawns were fed diets containing different concentrations of sodium alginate, and were exposed to different concentrations of copper sulphate, benzalkonium chloride (BKC), and trichlorfon. Results showed that PE mRNA expression of prawns was the highest in stage A, significantly decreased in stage B, and reached the lowest level in stages D0/D1. The PE transcript was significantly higher in prawns fed the 1.0 gkg(-1) sodium alginate-containing diet than those fed the 2.0 gkg(-1) sodium alginate-containing diet and those fed the control diet. PE transcripts significantly decreased in prawns exposed to 0.1-0.4 mgL(-1) copper sulphate after 96 h, 0.3-1.0 mgL(-1) BKC after 96 h, and 0.2-0.4 mgL(-1) trichlorfon after 48 h. It was concluded that the status of PE gene expression was seriously affected by the moult cycle, immunostimulant, and chemotherapeutants. PMID:17056274

Liu, Chun-Hung; Yeh, Shinn-Pyng; Hsu, Pei-Yi; Cheng, Winton

2007-04-01

39

GYRKPPFNGSIFamide (Gly-SIFamide) Modulates Aggression in the Freshwater Prawn Macrobrachium rosenbergii  

PubMed Central

The freshwater prawn Macrobrachium rosenbergii is a tropical crustacean with characteristics similar to those of lobsters and crayfish. Adult males develop through three morphological types—small (SC), yellow (YC), and blue claws (BC)—with each representing a level in the dominance hierarchy of a group, BC males being the most dominant. We are interested in understanding the role played by neuropeptides in the mechanisms underlying aggressive behavior and the establishment of dominance hierarchies in this type of prawn. SIFamides are a family of arthropod peptides recently identified in the central nervous system of insects and crustaceans, where it has been linked to olfaction, sexual behavior, and gut endocrine functions. One of the six SIFamide isoforms, GYRKPPFNGSIFamide (Gly-SIFamide), is highly conserved among decapod crustaceans such as crabs and crayfish. We wanted to determine whether Gly-SIFamide plays a role in modulating aggression and dominant behavior in the prawn. To do this, we performed behavioral experiments in which interactions between BC/YC pairs were recorded and quantified before and after injecting Gly-SIFamide directly into the circulating hemolymph of the living animal. Behavioral data showed that aggression among interacting BC/YC prawns was enhanced by injection of Gly-SIFamide, suggesting that this neuropeptide does have a modulatory role for this type of behavior in the prawn. PMID:20040755

Vázquez-Acevedo, Nietzell; Rivera, Nilsa M.; Torres-González, Alejandra M.; Rullan-Matheu, Yarely; Ruíz-Rodríguez, Eduardo A.; Sosa, María A.

2010-01-01

40

Lipid peroxidation and antioxidant defence status during larval development and metamorphosis of giant prawn, Macrobrachium rosenbergii.  

PubMed

In the present communication we studied the involvement of reactive oxygen species and alteration in antioxidant defence status during larval development and metamorphosis of giant prawn, Macrobrachium rosenbergii. Overall results indicate that there was a decline in endogenous lipid peroxidation level during larval development. Activity of superoxide dismutase was the lowest in early larval stages (Zoea-I and II) and thereafter increased in V and VI stages, followed by a decrease in the subsequent larval stages. Catalase and glutathione peroxidase did not exhibit specific pattern of changes during development. Reduced glutathione content exhibited an incremental increase during larval progression until metamorphosis. Ascorbic acid content of the larval tissue remained unaltered during development but a sharp fall was marked in its content in the post-larvae. Hence it is concluded that early larvae face high oxidative stress as evident from the high content of thiobarbituric acid reactive substances. This may be due to direct exposure of larvae to ambient oxygen of the water as well as their low antioxidant potential. However, during development with the augmentation in antioxidant reserve of the larval tissues a diminution in the oxidative stress was recorded. Thus it is presumed that antioxidant defences play an important role in providing protection to the developing larvae from oxidative assault during larval progression and metamorphosis. PMID:12927897

Dandapat, Jagneshwar; Chainy, Gagan B N; Rao, K Janardhana

2003-07-01

41

Ammonia toxicity as a criterion for the evaluation of larval quality in the prawn Macrobrachium rosenbergii.  

PubMed

The feasibility of a short-term ammonia toxicity test as an evaluation criterion for larval quality was assessed in three trials. In each one, Macrobrachium rosenbergii larvae originating from the same spawn were nutritionally differentiated in two groups by feeding them either a nutrient-rich (Artemia nauplii enriched for 24 h with n-3 highly unsaturated fatty acids (HUFA) and ascorbic acid (AA)) or a nutrient-poor diet (Artemia nauplii starved for 24 h). Throughout their development, larvae from both treatments were exposed during 24 h to six concentrations of total ammonia (NH(4)(+)+NH(3)) and a control (no ammonia added). Based on mortality rates, the median lethal concentration for 50% of the population (LC(50)) was estimated. As expected from earlier work, larvae fed the optimal diet presented higher n-3 HUFA and AA contents as well as higher growth and metamorphosis rates. From the moment the effect of diet quality was analytically detectable in the tissues of the larvae, the ammonia test was able to distinguish both groups of larvae. Differences in ammonia tolerance were observed as early as larval stage 4 and remained evident throughout larval development. The short-term ammonia toxicity test proved to be a valuable, sensitive and reproducible criterion for the establishment of larval quality. PMID:11790354

Cavalli, R O; Berghe, E V; Lavens, P; Nguyen, T T; Wille, M; Sorgeloos, P

2000-03-01

42

Transfer of foreign gene to giant freshwater prawn (Macrobrachium rosenbergii) by spermatophore-microinjection.  

PubMed

We developed a spermatophore-microinjection (SMI) technique that allows exogenous DNA fragments to be transferred easily into the giant freshwater prawn (Macrobrachium rosenbergii), an important aquacultural shellfish and aquatic invertebrate model. From 28 to 1, 000 ng of the circular plasmid pGL, in a total volume of 1 microl, were directly microinjected into spermatophores. Fertilization and hatching of prawns created with SMI were completed in vivo. Fertilization and hatching rates in the SMI treatments did not differ from those of the untreated control group. The genomes of free swimming, SMI-created larvae (21 days after fertilization) were analyzed using PCR and Southern blot analyses. A product with a molecular mass of 680 bp was amplified. It corresponded to amplifications of pGL, and Southern blot analysis revealed that the amplified band was positive. The gene transfer rate was primarily dependent on the concentration of DNA during SMI. The higher the concentration of pGL, the higher the rate of gene transfer. PCR and Southern blot analyses detected the existence of foreign DNA in 16 of 23 samples (70%) of genomic DNA isolated from hatched larvae in the 750 ng pGL SMI treatment. SMI, described here for the first time, is the simplest and most efficient method for mass producing transgenic giant freshwater prawns. PMID:10813846

Li, S S; Tsai, H J

2000-06-01

43

Impact of TBT on the vitellogenesis and sex hormones in freshwater prawn Macrobrachium rosenbergii (De Man, 1879)  

PubMed Central

Background Tributyltin (TBT) is a ubiquitous persistent xenobiotic that can be found in freshwater, estuarine and marine ecosystem. TBT is a strong endocrine disrupting compound (EDC) that can cause toxic threat to aquatic organisms. Imposex, sexual deformities and endocrine dysfunctions are the causes of TBT to most of the aquatic organisms. Effect of TBT on the vitellogenesis and sex hormonal changes in Macrobrachium rosenbergii has never been reported. Hence, the present investigation was undertaken to find out the impact of TBT on histological changes in the different reproductive tissues, sex hormonal alterations and level of biomarkers like vitellogenin and vitellin in M. rosenbergii. Results The present investigation documents the possible impact of tributyltin (TBT) on the vitellogenesis in freshwater female prawn M. rosenbergii. TBT at 10 ng/l, 100 ng/l and 1000 ng/l concentrations were exposed individually to prawns for a period of three months. At higher concentration of 1000 ng/l, the ovarian development was arrested and ovary remained at spent stage. At lower concentration of TBT (10 ng/l), the development proceeded up to early vitellogenic stage. At intermediate concentration of 100 ng/l TBT, the ovary remained at pre vitellogenic stage and thereafter no development was noticed. Histological results indicated the normal ovarian development with vitellogenic oocytes, filled with yolk globules in control prawn. On the other hand, the TBT treated groups showed reduction in yolk globules, fusion of developing oocytes and abundance of immature oocytes. Immunofluorescence staining denoted the remarkable reduction in vitellin content in ovary of TBT treated prawn. Hence, TBT had conspicuously inhibited the vitellogenesis by causing hormonal imbalance in M. rosenbergii. Conclusion TBT had notably inhibited the vitellogenesis due to hormonal imbalance. This endocrine dysfunction ultimately impaired the oogenesis in the freshwater female prawn M. rosenbergii. PMID:23634699

2013-01-01

44

Genetic Inheritance of Female and Male Morphotypes in Giant Freshwater Prawn Macrobrachium rosenbergii  

PubMed Central

Giant freshwater prawn (GFP) Macrobrachium rosenbergii is unique with males categorized in five different morphotypes (small claw, orange claw, blue claw, old blue claw and no claw males) and females in three reproductive statuses (mature ovary, berried and spawned females). In the present study we examined genetic inheritance of female and male morphotypes, their body weights and genetic associations between morphotypes and body traits. Restricted maximum likelihood fitting a multi-trait animal model was performed on a total of 21,459 body records collected over five generations in a GFP population selected for high growth rate. The estimates of variance components showed that there were substantial differences in additive genetic variance in body weight between male morphotypes. The low and significantly different from one genetic correlations between the expressions of body weight in male morphotypes also suggest that these traits should be treated as genetically different traits in selective breeding programs. By contrast, body weights of female types are essentially the same characters as indicated by the high genetic correlations between homologous trait expressions. In addition to body weight, male morphotypes and female reproductive statuses were treated as traits in themselves and were analysed as binary observations using animal and sire linear mixed models, and logit and probit threshold models. The estimates of heritability back-transformed from the liability scale were in good agreement with those obtained from linear mixed models, ranging from 0.02 to 0.43 for male morphotypes and 0.06 to 0.10 for female types. The genetic correlations among male morphoptypes were generally favourable. Body weight showed negative genetic associations with SM (?0.96), whereas those of body weight with other male morphotypes were positive (0.25 to 0.76). Our results showed that there is existence of heritable (additive genetic) component for male morphotypes, giving prospects for genetic selection to change population structure of GFP. PMID:24587246

2014-01-01

45

Lactococcus lactis subspecies lactis also causes white muscle disease in farmed giant freshwater prawns Macrobrachium rosenbergii.  

PubMed

From May to August 2001 in Taiwan, 27 farms for the giant freshwater prawn Macrobrachium rosenbergii experienced white tail disease outbreaks in animals approximately 3 to 5 mo old, with total lengths from 6 to 8 cm. Examination of the infected prawns revealed not only previously reported Lactococcus garvieae (16 farms) but also the novel L. lactis subsp. lactis (10 farms). One farm had shrimp infected with both bacteria. In the farms with L. lactis infections, the cumulative mortality was approximately 25 to 60%. Gross signs of disease were opaque and whitish muscles, while histopathology included marked edema and necrotic lesions, with inflammation in the muscles and hepatopancreas. Bacteria isolated using brain/heart infusion medium or tryptic soy agar were Gram-positive and ovoid. Eleven isolates from different farms were identified as L. lactis subsp. lactis using API 20 Strep and Rapid ID32 Strep tests and using PCR assays specific for the L. lactis subsp. lactis 16S rDNA gene (650 bp amplicon) and for the 16S to 23S rDNA interspacer region (380 bp amplicon). In addition, sequencing of the full 16S rDNA genes of 2 of the isolates (MR17 and MR26; GenBank Accession Numbers AF493058 and AF493057, respectively) revealed 99.9% identity between the isolates and 98.7% identity to several complete 16S rRNA sequences of L. lactis subsp. lactis at GenBank. Experimental infections with our isolates gave gross signs and histopathological changes similar to those seen in naturally infected prawns. The mean lethal dose of 4 isolates and the reference strain L. lactis subsp. lactis BCRC 10791 ranged from 4.2 x 10(6) to 2.5 x 10(7) colony-forming units prawn(-1), indicating virulence similar to that previously reported for L. garvieae. This is the first report confirming L. lactis subsp. lactis as a pathogen in juvenile and adult prawns from aquaculture. PMID:18429437

Wang, Pei-Chi; Lin, Yu-De; Liaw, Li-Ling; Chern, Red-Shiung; Chen, Shih-Chu

2008-03-01

46

Isolation and characterization of a female-specific DNA marker in the giant freshwater prawn Macrobrachium rosenbergii  

PubMed Central

In this study, a female-specific DNA marker in the freshwater prawn Macrobrachium rosenbergii was identified through amplified fragment length polymorphism (AFLP). The AFLP-derived sequence-characterized amplified region (SCAR) marker was tested in over 200 individuals, giving reproducible sex identification. Further molecular characterization of the sex-marker's genomic region (?3?kb long) revealed the presence of tandem and inverted repeats. The ?3-kb sequence was identified both in male and female prawns, but with subtle differences: a deletion of 3?bp (present in female prawn but absent in male prawn) identified upstream of the SCAR marker sequence and two female-specific single-nucleotide polymorphisms, both indicating that male prawns are homozygous, whereas female prawns are heterozygous in this locus. Fluorescent in situ hybridization showed the ?3-kb sequence to be unique: to the best of our knowledge, this is the first report of a unique sex-specific sequence observed in situ in crustaceans. The sex-specific marker identified in M. rosenbergii may have considerable applied merit for crustacean culture in that it will enable the determination of genetic sex at early developmental stages when phenotypic differences are not identifiable. PMID:21522169

Ventura, T; Aflalo, E D; Weil, S; Kashkush, K; Sagi, A

2011-01-01

47

Effect of benzalkonium chloride stress on immune resistance and susceptibility to Lactococcus garvieae in the giant freshwater prawn Macrobrachium rosenbergii.  

PubMed

Addition of benzalkonium chloride (BKC) at 0, 0.3, 0.6 and 1.0 mg l(-1) to tryptic soy broth (TSB) had no effect on growth of Lactococcus garvieae, a bacterial pathogen of the giant freshwater prawn Macrobrachium rosenbergii. However, injection of the cultured cells into prawns at a dose of 4 x 10(6) colony-forming units (cfu) prawn(-1) resulted in significantly higher mortality at 120 h (p < 0.05) in prawns injected with cells grown in the absence of BKC than in prawns injected with cells grown in the presence of BKC. In other experiments, prawns were injected with TSB-grown L. garvieae (4 x 10(6) and 3 x 10(5) cfu prawn(-1)) and then held in water containing BKC at 0, 0.3, 0.6 and 1.0 mg l(-1). After 120 h, mortality was significantly higher in all the BKC treatments than in the control without BKC. Prawns showed no significant differences in total hemocyte count (THC) or differential hemocyte count (DHC) amongst treatment and control groups. However, 96 h exposure to 0.3 mg l(-1) BKC or more resulted in a decrease in phenoloxidase activity and an increase in respiratory burst to levels considered to be cytoxic. In summary, exposure of L. garvieae to BKC at 0.3 mg l(-1) or more decreased its virulence to M. rosenbergii, while exposure of M. rosenbergii to BKC at 0.3 mg l(-1) or more increased its susceptibility to L. garvieae infection. PMID:12691193

Cheng, Winton; Wang, Ching-Hsien; Chen, Jiann-Chu

2003-02-27

48

Morphological and histological studies on freshwater prawn Macrobrachium rosenbergii (de man) irradiated with (60)Co gamma radiation.  

PubMed

This study was framed to investigate the (60)Co gamma radiation induced morphological and histological variations in freshwater prawn Macrobrachium rosenbergii. The LD50 value of (60)Co gamma irradiated M. rosenbergii observed (by probit analysis) at 30 Gy. Prawns were irradiated to four different dose levels (3 mGy, 30 mGy, 300 mGy and 3,000 mGy) using Theratron Phoenix TeleCobalt Unit [P-33] and one control group (without irradiation) maintained separately. Irradiated groups exhibited several morphological variations such as discoloration; damaged rostrum; opaque coloration in cephalothorax; black bands and dot formation in abdomen; deformed uropods and telson in tail regions when compared with control group. The Hepato Somatic Index reflected the severity of radiation on hepatopancreas. Histological variations in gills, hepatopancreas and muscles of irradiated groups were observed. In gills, structural changes such as swollen and fused lamellae, abnormal gill tips, hyperplasic, necrotic and clavate-globate lamellae were observed in gamma irradiated prawns. Accumulation of hemocytes in hemocoelic space, interstitial sinuses filled with abnormal infiltrated hemocytes, the tubular epithelium with ruptured basal laminae, abnormal and coagulated lumen, necrotic tubules, thickened basal laminae, tissue debris, necrotic hepatocytes were observed in irradiated prawn hepatopancreas. In muscle, shrinkage of muscular fiber and necrotic musculature were observed in irradiated prawns. These structural alterations of the organs it is felt could affect the vital physiological functions such as respiration, osmotic and ionic regulation in gills and muscles; absorption, storage and secretion of the hepatopancreas which in turn could adversely affect the growth and survival of freshwater prawn M. rosenbergii. PMID:24140570

Stalin, A; Broos, K V; Sadiq Bukhari, A; Syed Mohamed, H E; Singhal, R K; Venu-Babu, P

2013-11-15

49

Dietary supplementation of zinc nanoparticles and its influence on biology, physiology and immune responses of the freshwater prawn, Macrobrachium rosenbergii.  

PubMed

The present study was conducted to assess the influence of dietary zinc nanoparticles (size 50 nm) on the growth, biochemical constituents, enzymatic antioxidant levels and the nonspecific immune response of the freshwater prawn, Macrobrachium rosenbergii post larvae (PL). The concentrations of dietary supplement zinc nanoparticles (ZnNPs) were 0, 10, 20, 40, 60 and 80 mg kg(-1) with the basal diet, and the level of Zn in ZnNP-supplemented diets were 0.71, 10.61, 20.73, 40.73, 60.61 and 80.60 mg kg(-1), respectively. ZnNP-incorporated diets were fed to M. rosenbergii PL (initial body weight, 0.18 ± 0.02 g) in a triplicate experimental setup for a period of 90 days. ZnNP supplemented feed fed PL up to 60 mg kg(-1) showed significantly (P < 0.05) improved performance in survival, growth and activities of digestive enzymes (protease, amylase and lipase). The concentrations of biochemical constituents (total protein, total amino acid, total carbohydrate and total lipid), total haemocyte count and differential haemocyte count were elevated in 10-60 mg kg(-1) ZnNP supplemented feed fed PL. However, the PL fed with 80 mg ZnNPs kg(-1) showed negative results. Activities of enzymatic antioxidants [superoxide dismutase (SOD) and catalase (CAT)], metabolic enzymes [glutamate-oxaloacetate transaminase (GOT) and glutamate-pyruvate transaminase (GPT)] and the process of lipid peroxidation (LPO) in the hepatopancreas and muscle showed no significant alterations in 10-60 mg kg(-1) ZnNP supplemented feed fed PL. Whereas, 80 mg ZnNPs kg(-1) supplemented feed fed PL showed significant elevations in SOD, CAT, LPO, GOT and GPT. Therefore, 80 mg ZnNPs kg(-1) was found to be toxic to M. rosenbergii PL. Thus, the study suggests that up to 60 mg ZnNPs kg(-1) can be supplemented for regulating survival, growth and immunity of M. rosenbergii. PMID:24874230

Muralisankar, Thirunavukkarasu; Bhavan, Periyakali Saravana; Radhakrishnan, Subramanian; Seenivasan, Chandirasekar; Manickam, Narasimman; Srinivasan, Veeran

2014-07-01

50

A new nodavirus is associated with covert mortality disease of shrimp.  

PubMed

A new nodavirus, named covert mortality nodavirus (CMNV), is associated with covert mortality disease of shrimp which has caused serious loss in China since 2009. Histopathological examination of shrimp suffering the disease revealed coagulative necrosis of striated muscle similar to typical histopathology features of infectious myonecrosis virus (IMNV), Penaeus vannamei nodavirus (PvNV) and Macrobrachium rosenbergii nodavirus (MrNV). However, shrimp suffering this disease tested negative for IMNV, MrNV and PvNV by reverse transcription (RT)-PCR. Additionally, eosinophilic inclusions were found in epithelium of the tubules in the hepatopancreas and lymphoid organ, and mass karyopyknotic nuclei existed in the muscle and lymphoid organ. The tubular epithelium of the hepatopancreas showed significant atrophy. A cDNA library was constructed from total RNA of infected shrimp. Sequencing and alignment analysis showed that one clone with an 1185 bp insert (designated CMNV-7) shared 54?, 53? and 39?% identity with the amino acid sequences of RNA-dependent RNA polymerase from Flock House virus, black beetle virus and MrNV. The results of fluorescence in situ hybridization showed that the hepatopancreas, striated muscle and lymphoid organ were positively reacting tissues. The mean size of negative-stained virus particles was 32 nm. In addition, a nested RT-PCR assay was developed for CMNV, and the RT-PCR detection results revealed that Fenneropenaeus chinensis, Litopenaeus vannamei and Marsupenaeus japonicus suffering from this disease were CMNV-positive. PMID:25205685

Zhang, Qingli; Liu, Qun; Liu, Shuang; Yang, Haolin; Liu, Sun; Zhu, Luoluo; Yang, Bing; Jin, Jiting; Ding, Lixue; Wang, Xiuhua; Liang, Yan; Wang, Qintao; Huang, Jie

2014-12-01

51

Characterization of two novel ADP ribosylation factors from giant freshwater prawn Macrobrachium rosenbergii and their responses to WSSV challenge.  

PubMed

ADP-ribosylation factors (Arfs) are small GTP-binding proteins that have an essential function in intracellular trafficking and organelle structure. To date, little information is available on the Arfs in the economically important giant freshwater prawn Macrobrachium rosenbergii and their relationship to viral infection. Here we identified two Arf genes from M.?rosenbergii (MrArf1 and MrArf2) for the first time. Phylogenetic analysis showed that MrArf1, together with MjArf1 from shrimp Marsupenaeus japonicus belonged to Class I Arfs. By contrast, MrArf2 didn't not match any of the Arfs classes of I/II/III, although it could be clustered with an Arf protein from M.?japonicas called MjArfn, which may represent an analog of the Arf. MrArf1 was ubiquitously expressed in all the examined tissues, with the highest transcription level in the hepatopancreas, whereas MrArf2 was only highly expressed in the hepatopancreas and exhibited very low levels in the heart, stomach, gills and intestine. The expression level of MrArf1 in the gills was down-regulated post 24?h WSSV challenge, and reached the maximal level at 48?h. MrArf1 in the hepatopancreas went up from 24 to 48?h WSSV challenge. MrArf2 transcript in the gill also went down at 24?h and then was upregulated at 48?h WSSV challenge. MrArf2 increased significantly in the hepatopancreas 24?h after infection and then went down at 48?h WSSV challenge. RNAi results showed that knockdown of MrArf1 or MrArf2 could inhibit the expression of the envelope protein gene vp28 of the WSSV. So, it could be speculated that MrArf1 and MrArf2 might play important roles in the innate immune system against WSSV infection. PMID:25451300

Ding, Zheng-Feng; Ren, Jie; Tan, Jing-Min; Wang, Zheng; Yin, Shao-Wu; Huang, Ying; Huang, Xin; Wang, Wen; Lan, Jiang-Feng; Ren, Qian

2015-01-01

52

Function of a novel C-type lectin with two CRD domains from Macrobrachium rosenbergii in innate immunity.  

PubMed

C-type lectins play crucial roles in innate immunity. In the present study, a novel C-type lectin gene, designated as MrCTL, was identified from Macrobrachium rosenbergii. MrCTL contains 2 carbohydrate-recognition domains (CRDs), namely MrCRD1 and MrCRD2. The MrCRD1 contains a QEP motif and MrCRD2 contains a motif of EPD. MrCTL was mainly expressed in the hepatopancreas. The expression level of MrCTL in hepatopancreas was significantly upregulated after a challenge with Vibrio parahaemolyticus or White spot syndrome virus (WSSV). The recombinant MrCTL, MrCRD1 and MrCRD2 have an ability to agglutinate both Gram-negative (V. parahaemolyticus) and Gram-positive bacteria (Staphylococcus aureus) in a calcium dependent manner. The recombinant MrCTL, MrCRD1 and MrCRD2 bind directly to all tested microorganisms. All these results suggested that MrCTL may have important roles in immune defense against invading pathogens in prawns. PMID:25475962

Huang, Xin; Huang, Ying; Shi, Yan-Ru; Ren, Qian; Wang, Wen

2015-03-01

53

Identification and Characterization of Differentially Expressed Transcripts in the Gills of Freshwater Prawn (Macrobrachium rosenbergii) under Salt Stress  

PubMed Central

The giant freshwater prawn, Macrobrachium rosenbergii, is an economically important species. It is a euryhaline shrimp, surviving in wide-range salinity conditions. A change in gene expression has been suggested as an important component for stress management. To better understand the osmoregulatory mechanisms mediated by the gill, a subtractive and suppressive hybridization (SSH) tool was used to identify expressed transcripts linked to adaptations in saline water. A total of 117 transcripts represented potentially expressed under salinity conditions. BLAST analysis identified 22% as known genes, 9% as uncharacterized showing homologous to unannotated ESTs, and 69% as unknown sequences. All the identified known genes representing broad spectrum of biological pathways were particularly linked to stress tolerance including salinity tolerance. Expression analysis of 10 known genes and 7 unknown/uncharacterized genes suggested their upregulation in the gills of prawn exposed to saline water as compared to control indicating that these are likely to be associated with salinity acclimation. Rapid amplification of cDNA ends (RACE) was used for obtaining full-length cDNA of MRSW-40 clone that was highly upregulated during salt exposure. The sequenced ESTs presented here will have potential implications for future understanding about salinity acclimation and/or tolerance of the prawn. PMID:22619594

Barman, Hirak Kumar; Patra, Swagat Kumar; Das, Varsha; Mohapatra, Shibani Dutta; Jayasankar, Pallipuram; Mohapatra, Chinmayee; Mohanta, Ramya; Panda, Rudra Prasanna; Rath, Surya Narayan

2012-01-01

54

Effects of (60)Co gamma irradiation on behavior and gill histoarchitecture of giant fresh water prawn Macrobrachium rosenbergii (DE MAN).  

PubMed

Present study was designed to observe the effects of (60)Co gamma radiation in behavioral and histological changes in the gills of giant fresh water prawn Macrobrachium rosenbergii. The adult prawns were irradiated with four different dose levels (3mGy, 30mGy, 300mGy and 3000mGy) and the control group (without irradiation) was maintained separately. Behavioral changes like hyperactivity, loss of balance, reduced swimming rate, slower rate of food intake and convulsions were observed in higher dose levels of 300mGy and 3000mGy. The histological alterations such as accumulated haemocytes in haemocoelic spaces, abnormal gill tips, lifted lamellar epithelium, swollen and fused lamellae, hyperplasic, necrotic, clavate-globate and complete disorganization of lamellae were observed in (60)Co gamma irradiated prawns. Significantly more considerable histological alterations were observed in the highest dose level of 3000mGy, but no mortality was evidenced. This study serves as biomonitoring tool to assess the radiation pollution in the aquatic environment. PMID:23587558

Stalin, A; Broos, K V; Sadiq Bukhari, A; Syed Mohamed, H E; Singhal, R K; Venu-babu, P

2013-06-01

55

Effects of Nitrite Exposure on Acid–Base Balance, Respiratory Protein, and Ion Concentrations of Giant Freshwater Prawn Macrobrachium rosenbergii at Low pH  

Microsoft Academic Search

.  \\u000a \\u000a Macrobrachium rosenbergii that had been exposed individually for 24 h to 0 (control), 2, 5, 10 mg\\/L nitrite-N (nitrite as nitrogen) at 4.3 and 7.7\\u000a pH levels were examined for hemolymph nitrite-N, oxyhemocyanin, protein, acid–base balance, ion concentrations, and ammonia-N\\u000a (ammonia as nitrogen) excretion. Hemolymph oxyhemocyanin, protein, pH, HCO3\\u000a \\u000a ? , TCO2, osmolality, and ion concentrations were inversely related

J.-C. Chen; Y. Lee

1997-01-01

56

Characterization of a gC1qR from the giant freshwater prawn, Macrobrachium rosenbergii.  

PubMed

gC1qR, as a multicompartmental and a multifunctional protein, plays an important role in innate immunity. In this study, a gC1qR homolog (MrgC1qR) in the giant freshwater prawn, Macrobrachium rosenbergii was identified. MrgC1qR, a 258-amino-acid polypeptide, shares high identities with gC1qR from other species. MrgC1qR gene was expressed in different tissues and was highest expressed in the hepatopancreas. In addition, the MrgC1qR transcript was significantly enhanced after 6 h of white spot syndrome virus (WSSV) infection or post 2 h, 24 h of Vibrio anguillarum challenge compared to appropriate controls. Moreover, recombinant MrgC1qR (rMrgC1qR) had bacterial binding activity, the result also revealed that rMrgC1qR could bind pathogen-associated molecular patterns (PAMPs) such as LPS or PGN, suggesting that MrgC1qRmight function as a pathogen-recognition receptor (PRR). Furthermore, glutathione S-transferase (GST) pull-down assays showed that rMrgC1qR with GST-tag could bind to rMrFicolin1 or rMrFicolin2 with His-tag. Altogether, these results may demonstrate a role for MrgC1qR in innate immunity in the giant freshwater prawns. PMID:25555810

Ye, Ting; Huang, Xin; Wang, Xian-Wei; Shi, Yan-Ru; Hui, Kai-Min; Ren, Qian

2015-03-01

57

Detection and genetic profiling of infectious hypodermal and haematopoietic necrosis virus (IHHNV) infections in wild berried freshwater prawn, Macrobrachium rosenbergii collected for hatchery production.  

PubMed

Infectious hypodermal and haematopoietic necrosis virus (IHHNV) has been detected widely in penaeid culture facilities in Asia and the Americas. IHHNV infection on sub-adult and postlarvae of the giant freshwater prawn, Macrobrachium rosenbergii which had caused up to 80% mortalities was first reported in Southeast Taiwan in 2006. In Malaysia, although, there has been no report on IHHNV infections in M. rosenbergii, preliminary work suggests that there is an urgent need to setup a screening protocol for IHHNV for both wild and cultured populations. In this study, polymerase chain reaction based screening was carried out on 30 randomly sampled berried wild M. rosenbergii before and after spawning. All samples did not showed any sign of IHHNV infection. However, the results showed that 20% of the samples were IHHNV positive. Sequence analysis of the amplified band using NCBI-BLAST showed that the putative IHHNV sequence had 98% nucleotide sequence (388 bp) identity with the IHHNV isolate AC-05-005 non-structural protein 1 gene and seven other IHHNV strains in the data bank further affirming the suggestion on the presence of IHHNV in wild freshwater prawn populations in Malaysia. PMID:21755294

Hazreen Nita, M K; Kua, B C; Bhassu, S; Othman, R Y

2012-04-01

58

Identification of lectin isoforms in juvenile freshwater prawns Macrobrachium rosenbergii (DeMan, 1879).  

PubMed

From the serum of juvenile freshwater prawns, we isolated by affinity chromatography on glutaraldehyde-fixed rat erythrocytes stroma, immobilized in Sephadex G-25, a sialic acid specific lectin of 9.6 kDa per subunit. Comparative analysis against adult organisms purified lectin, by chromatofocusing, showed that the lectin from juvenile specimens is composed by four main isoforms with a pI of 4.2, 4.6, 5.1, and 5.6, whereas the lectin from adults is eluted at pH 4.2. The amino acid composition of the lectin obtained from adult and juvenile stages suggest identity, but the compositions are not identical since a higher content of carbohydrates was found in the lectin from younger organisms. The freshwater prawn lectin showed specificity toward N-acetylated amino sugar residues such as GlcNAc, GalNAc, Neu5Ac and Neu5,9Ac; but in juvenile organisms the lectin showed three times less hemagglutinating activity than the lectin from adults. Both lectins agglutinated rat, rabbit and chicken erythrocytes, indicating that Neu5,9Ac in specific O-glycosydically linked glycans seems to be relevant for the interaction of M. rosenbergii lectins with their specific cellular receptor. Our results suggest that the physicochemical characteristics of the lectin from the freshwater prawn are regulated through maturation. PMID:11261843

Zenteno, R; Vázquez, L; Martínez-Cairo, S; Bouquelet, S; Agundis, C; Zenteno, E

2000-05-01

59

De Novo Transcriptome Sequencing Analysis and Comparison of Differentially Expressed Genes (DEGs) in Macrobrachium rosenbergii in China  

PubMed Central

Giant freshwater prawn (GFP; Macrobrachium rosenbergii) is an exotic species that was introduced into China in 1976 and thereafter it became a major species in freshwater aquaculture. However the gene discovery in this species has been limited to small-scale data collection in China. We used the next generation sequencing technology for the experiment; the transcriptome was sequenced of samples of hepatopancreas organ in individuals from 4 GFP groups (A1, A2, B1 and B2). De novo transcriptome sequencing generated 66,953 isogenes. Using BLASTX to search the Non-redundant (NR), Search Tool for the Retrieval of Interacting Genes (STRING), and Kyoto Encyclopedia of Genes and Genome (KEGG) databases; 21,224 unigenes were annotated, 9,552 matched unigenes with the Gene Ontology (GO) classification; 5,782 matched unigenes in 25 categories of Clusters of Orthologous Groups of proteins (COG) and 20,859 unigenes were consequently assigned to 312 KEGG pathways. Between the A and B groups 147 differentially expressed genes (DEGs) were identified; between the A1 and A2 groups 6,860 DEGs were identified and between the B1 and B2 groups 5,229 DEGs were identified. After enrichment, the A and B groups identified 38 DEGs, but none of them were significantly enriched. The A1 and A2 groups identified 21,856 DEGs in three main categories based on functional groups: biological process, cellular_component and molecular function and the KEGG pathway defined 2,459 genes had a KEGG Ortholog - ID (KO-ID) and could be categorized into 251 pathways, of those, 9 pathways were significantly enriched. The B1 and B2 groups identified 5,940 DEGs in three main categories based on functional groups: biological process, cellular_component and molecular function, and the KEGG pathway defined 1,543 genes had a KO-ID and could be categorized into 240 pathways, of those, 2 pathways were significantly enriched. We investigated 99 queries (GO) which related to growth of GFP in 4 groups. After enrichment we identified 23 DEGs and 1 KEGG PATHWAY ‘ko04711’ relation with GFP growth. PMID:25329319

Liu, Qigen

2014-01-01

60

Function of an anti-lipopolysaccharide factor (ALF) isoform isolated from the hemocytes of the giant freshwater prawn Macrobrachium rosenbergii in protecting against bacterial infection.  

PubMed

In this study, a 780-bp full-length cDNA encoding Macrobrachium rosenbergii anti-lipopolysaccharide factor (MrALF) from hemocytes was cloned and identified. The ALF isoform exhibited immune activities, and its concentration in hemolymph was determined. An in vivo expression study showed that the ALF mRNA level of hemocytes could be induced by lipopolysaccharides (LPSs) in an exposure time-dependent manner. Purified recombinant MrALF (rMrALF) expressed in the yeast Pichia pastoris SMD1168 eukaryotic protein expression system demonstrated antibacterial activity against the Gram-negative prawn pathogen Aeromonas hydrophila (minimum inhibitory concentration (MIC)=0.806?M, minimum bactericidal concentration (MBC)=1.606?M) but not the Gram-positive pathogen Lactococcus garvieae exposed to 25.696?M of rALF. However, rMrALF can bind to Gram-negative and -positive bacteria. An in vivo expression study demonstrated that the ALF concentrations in prawn hemocytes and plasma were 0.176?M and 0.168?M, respectively; following LPS treatment for 6h, the corresponding concentrations were 0.133?M in hemocytes and 0.272?M in plasma. Furthermore, the percentage of hemocytes phagocytosing bacteria cells was higher in hemoyctes previously treated with MrALF than those treated with sterile medium. These results suggest that in the innate immune response of M. rosenbergii, the MrALF from hemocytes may play an opsonin during a bacterial invasion. PMID:24333685

Liu, Chia-Chen; Chung, Chien-Pang; Lin, Chang-Yi; Sung, Hung-Hung

2014-02-01

61

Effects of salinity on rates of protein synthesis and oxygen uptake in the post-larvae and juveniles of the tropical prawn Macrobrachium rosenbergii (de Man).  

PubMed

Protein synthesis is a major determinant of growth and yet little is known about the environmental factors that influence protein synthesis rates in farmed freshwater prawns. To this end, post-larvae and juveniles of Macrobrachium rosenbergii were exposed to various salinities (0, 14, 30 per thousand) to determine whole-animal rates of fractional protein synthesis (k(s)) and oxygen uptake. In the post-larvae that migrate upstream from brackish to freshwater areas, whole-animal k(s) was unaffected by salinity, but rates of oxygen uptake were significantly lower at 14 per thousand. In the freshwater juveniles, a different response was observed, as mean k(s) was significantly higher at 14 per thousand compared with 0 per thousand, but rates of oxygen uptake remained unchanged. Such differences are thought to be related to the energetic costs of osmoregulation and to the ability to maintain osmotic gradients in freshwater. In an additional experiment, acclimation temperature (20, 26, 30 degrees C) had a direct effect on k(s) in juveniles held at 0 per thousand. In all cases, changes in k(s) resulted from alterations in RNA activity at constant RNA capacity. In juveniles at least, whole-animal rates of protein synthesis were highest at 14 per thousand and 30 degrees C which corresponds to the optimal salinity and temperature recommended for the growth and culture of M. rosenbergii. PMID:19049893

Intanai, I; Taylor, E W; Whiteley, N M

2009-03-01

62

Simultaneous identification and quantification of 4-cumylphenol, 2,4-bis-(dimethylbenzyl)phenol and bisphenol A in prawn Macrobrachium rosenbergii.  

PubMed

Bisphenol A (BPA), 4-cumylphenol (4-CP) and 2,4-bis-(dimethylbenzyl)phenol (2,4-DCP) are all high production volume chemicals and widely used in plastic and other consumer products. During the past two decades, BPA has attracted a great deal of scientific and public attention due to its presence in the environment and estrogenic property. Although 4-CP and 2,4-DCP are much more estrogenic and toxic than BPA, little information is available about their occurrence and fate in the environment. In this study, a rapid, selective, accurate and reliable analytical method was developed for the simultaneous determination of 4-CP, 2,4-DCP and BPA in prawn Macrobrachium rosenbergii. The method comprises an ultrasound-accelerated extraction followed by capillary gas chromatographic (GC) separation. The detection limits range from 1.50 to 36.4 ng kg(-1) for the three alkylphenols. The calibration curves are linear over the concentration range tested with the coefficients of determination, R(2), greater than 0.994. The developed method was successfully applied to the simultaneous determination of 4-CP, 2,4-DCP and BPA in prawn samples. The peak identification was confirmed using GC-MS. Bisphenol A, 2,4-bis-(dimethylbenzyl)phenol and 4-cumylphenol were found in prawn samples in the concentration ranges of 0.67-5.51, 0.36-1.61, and 0.00-1.96 ng g(-1) (wet weight), respectively. All relative standard deviations are less than 4.8%. At these environmentally relevant concentration levels, 4-CP, 2,4-DCP and BPA may affect the reproduction and development of aquatic organisms, including negative influence on crustaceans' larval survival, molting, metamorphosis and shell hardening. This is the first study reported on the occurrence of 4-CP, 2,4-DCP and BPA in prawn M. rosenbergii. PMID:24560775

Zuo, Yuegang; Zhu, Zhuo

2014-07-01

63

L-( sup 3 H) glutamate binding to a membrane preparation from the optic lobe of the giant freshwater prawn Macrobrachium rosenbergii de Man  

SciTech Connect

Membrane preparation from the optic lobe of the giant freshwater prawn, Macrobrachium rosenbergii de Man, was examined for the presence of specific L-({sup 3}H) glutamate binding. The optic lobes were isolated from live animals. The tissue was homogenized and the membrane fraction isolated by differential centrifugation. The membrane suspension was incubated with 10-1,000 nM of L-({sup 3}H) glutamate at 37{degree}C for 60 min. Nonspecific binding was determined by incubating the mixture with 100 {mu}M L-glutamate. L-({sup 3}H) glutamate specifically bound to the membrane fraction with a dissociation equilibrium constant (Kd) of 205 nM and maximum number of binding sites (Bmax) of 2.04 n mol/mg protein. By using LIGAND computerized program, the saturation isotherm binding pattern indicates a single type of binding. To determine the type of glutamate receptors, competitive inhibition and IC{sub 50} of several glutamate agonists and antagonists were determined. The study reveals a metabotropic type of binding site.

Pratumtan, P.; Govitrapong, P.; Withyachumnarnkul, B.; Poolsanguan, B. (Mahidol Univ., Bangkok (Thailand) Mahidol Univ., Nakorn Pathom (Thailand))

1991-01-01

64

Structure of the olfactory receptor organs, their GABAergic neural pathways, and modulation of mating behavior, in the giant freshwater prawn, Macrobrachium rosenbergii.  

PubMed

In the giant male prawn, Macrobrachium rosenbergii, the olfactory system is thought to be the main pathway for modulating sexual behavior through pheromone perception. In this report, we first used gross anatomical, histological, and SEM methods to describe the structures of the olfactory receptors (sensilla setae), their neural pathways, and possible role in modulating mating behavior. On the surfaces of antennule and antenna filaments there are four types of sensory receptors, viz single spike-like setae, single flagellum-like setae, multiple flagella-like setae, and aesthetascs (ASs). The ASs, which had previously been proposed to be odor receptor setae, are found only on the short filament of lateral antennule (slAn). Each AS on the slAn connects with olfactory receptor neurons (ORNs), whose axons form an outer central antennule nerve (ocAnNv), which then connects with the olfactory neutrophil (ON) of the brain. Thus, the slAn is the major olfactory organ that conveys sensory inputs from each AS to the ON within the deutocerebrum. GABA immunoreactivity was present in ASs, neurons of ORNs, inner central antennular, lateral tegumentary nerve, ocAnNv and the ON, inferring that GABA is the likely neurotransmitter in modulating olfaction. Disruption of the slAn by ablation or covering with Vaseline, resulted in significant reduction of mating behavior, indicating that this organ is crucial for sex pheromone perception. Identification of the active pheromones and further bioassays are now being performed. PMID:23495186

Kruangkum, Thanapong; Chotwiwatthanakun, Charoonroj; Vanichviriyakit, Rapeepun; Tinikul, Yotsawan; Anuracpreeda, Panat; Wanichanon, Chaitip; Hanna, Peter J; Sobhon, Prasert

2013-06-01

65

Expression of the male reproduction-related gene (Mar-Mrr) in the spermatic duct of the giant freshwater prawn, Macrobrachium rosenbergii.  

PubMed

Phosphorylated sperm proteins are crucial for sperm maturation and capacitation as a priori to their fertilization with eggs. In the freshwater prawn, Macrobrachium rosenbergii, a male reproduction-related protein (Mar-Mrr) was known to be expressed only in the spermatic ducts as a protein with putative phosphorylation and may be involved in sperm capacitation in this species. We investigated further the temporal and spatial expression of the Mar-Mrr gene using RT-PCR and in situ hybridization and the characteristics and fate of the protein using immunblotting and immunocytochemistry. The Mar-Mrr gene was first expressed in 4-week-old post larvae and the protein was produced in epithelial cells lining the spermatic ducts, at the highest level in the proximal region and decreased in the middle and distal parts. The native protein had a MW of 17 kDa and a high degree of serine/threonine phosphorylation. It was transferred from the epithelial cells to become a major protein at the anterior region of the sperm. We suggest that it is involved in sperm capacitation and fertilization in this open thelycal species and this is being investigated. PMID:22427066

Phoungpetchara, Ittipon; Tinikul, Yotsawan; Poljaroen, Jaruwan; Changklungmoa, Narin; Siangcham, Tanapan; Sroyraya, Morakot; Chotwiwatthanakun, Charoonroj; Vanichviriyakit, Rapeepun; Hanna, Peter J; Sobhon, Prasert

2012-06-01

66

Inter- and intra-individual variation in resting oxygen consumption in post-larvae of the giant freshwater prawn, Macrobrachium rosenbergii (De Man).  

PubMed

In a study of the factors that influence metabolic rate in the giant freshwater prawn Macrobrachium rosenbergii, resting oxygen consumption (ROC) was measured in 90 post-larvae ranging in size from 0.1 to 2.8 g. As in many other animal species, ROC was strongly negatively related to body weight. A stressful event (anaesthesia with or without tagging) caused a sharp increase in the ROC that disappeared over a time scale of hours. As has been demonstrated for other species of crustaceans, ROC was highest in prawns in the pre-moult stage. Individual differences in ROC among prawns handled in the same way and in the same moult stage persisted over a period of hours, but not over days. It remains unclear, therefore, whether early differences in resting metabolic rate can explain the conspicuous differences in growth rate that are found in this species during the first few weeks of life and that profoundly influence subsequent life history events. PMID:12020662

Taylor, Alan; Ross, Ben; McCauley, Shona; Brown, Janet H; Huntingford, Felicity

2002-06-01

67

Evaluation of paraprobiotic applicability of Lactobacillus plantarum in improving the immune response and disease protection in giant freshwater prawn, Macrobrachium rosenbergii (de Man, 1879).  

PubMed

Paraprobiotics, also known as ghost probiotics, are non-viable microbial cells which, when administered in adequate amounts, confer a benefit on the host. However, the advantage of non-viable microbes over their viable counterparts is a much debated topic in aquaculture. Therefore, the present study was conducted to evaluate paraprobiotic effect of heat-killed Lactobacillus plantarum on giant freshwater prawn Macrobrachium rosenbergii. A 90-day feeding trial was conducted by feeding prawn juveniles (mean weight ± SE: 0.54 ± 0.03 g) with three experimental diets prepared by supplementing basal diet (Crude protein: 38%; Gross energy: 387 kcal 100 g(-1)) with different concentrations of heat-killed probiotics bacteria viz. HKPB1 (10(7) cfu g(-1) diet), HKPB2 (10(8) cfu g(-1) diet), HKPB3 (10(9) cfu g(-1) diet) and control diet (unsupplemented diet). In the present study, growth parameters viz. WG % and SGR and feed utilization parameters viz. FCE, FCR and PER, though improved marginally in all experimental groups, were found to be insignificant (P > 0.05) compared to the control. The immune parameters viz. total hemocyte count (THC), phenol oxidase (PO) activity, respiratory burst (RB) activity and clearance efficiency were significantly improved (P < 0.05) with concurrent decrease (P < 0.05) in cumulative mortality against Aeromonas hydrophila challenge in all the experimental groups except for HKPB1, where PO and RB activity did not improve significantly (P > 0.05) compared to the control. Among the experimental groups, though the improvement in immune parameters was higher (P < 0.05) in HKPB2 and HKPB3 compared to HKPB1 and the control, no significant difference (P > 0.05) was observed between HKPB2 and HKPB3. The results obtained from the present study indicate that the application of heat-killed L. plantarum at a concentration of 10(8) cfu g(-1) diet, though not effective in augmenting the growth and feed utilization parameters, can significantly improve immune parameters and disease resistance of M. rosenbergii in the laboratory condition. PMID:25542379

Dash, Gyanaranjan; Raman, Ram Prakash; Pani Prasad, K; Makesh, M; Pradeep, M A; Sen, Swatipriyanka

2015-03-01

68

Cloning and immunoreactivity of the 5-HT1Mac and 5-HT2Mac receptors in the central nervous system of the freshwater prawn Macrobrachium rosenbergii  

PubMed Central

Biogenic amines are implicated in several mental disorders, many of which involve social interactions. Simple model systems, such as crustaceans, are often more amenable than vertebrates for studying mechanisms underlying behaviors. Although various cellular responses of biogenic amines have been characterized in crustaceans, the mechanisms linking these molecules to behavior remain largely unknown. Observed effects of serotonin receptor agonists and antagonists in abdomen posture, escape responses, and fighting have led to the suggestion that biogenic amine receptors may play a role in modulating interactive behaviors. As a first step in understanding this potential role of such receptors, we have cloned and fully sequenced two serotonin receptors, 5-HT1Mac and 5-HT2Mac, from the CNS of the freshwater prawn Macrobrachium rosenbergii, and have mapped their CNS immunohistochemical distribution. 5-HT1Mac was found primarily on the membranes of subsets of cells in all CNS ganglia, in fibers that traverse all CNS regions, and in the cytoplasm of a small number of cells in the brain, circum- and subesophageal ganglia (SEG), most of which also appear to contain dopamine. The pattern of 5-HT2Mac immunoreactivity was found to differ significantly, being found mostly in the central neuropil area of all ganglia, in glomeruli of the brain’s olfactory lobes, and in the cytoplasm of a small number of neurons in the SEG, thoracic and some abdominal ganglia. The observed differences in terms of localization, distribution within cells, and intensity of immunoreactive staining throughout the prawn’s CNS suggest that these receptors are likely to play different roles. PMID:19184976

Vázquez-Acevedo, Nietzell; Reyes-Colón, Dalynés; Ruíz-Rodríguez, Eduardo A.; Rivera, Nilsa M.; Rosenthal, Joshua; Kohn, Andrea B.; Moroz, Leonid L.; Sosa, María A.

2009-01-01

69

Preliminary obervations on use of ethanol distiller's by-products for polyculture of freshwater prawn (Macrobrachium rosenbergii) and golden shiner (Notemigonus crysoleucas)  

SciTech Connect

Two major by-products of ethanol distillation, corn distiller's solubles and corn distiller's mash, were evaluated for their potential use as a food source for freshwater prawn (Macrobrachium rosenbergii) and golden shiner (Notemigonus crysoleucas) in mid-western United States. Corn distiller's solubles were not found to be highly toxic to aquatic organisms at concentrations ranging up to 10,000 ppM. However, the high biological oxygen demand of the material requires that single applications not exceed 2000 ppM. Yield trials were conducted over a four month period in five 0.1 ha earthen ponds, located in proximity to an ethanol distillery. Each pond was stocked with 2000 postlarval shrimp (0.02 g mean weight). Three of these ponds were also each stocked with 75 adult golden shiner (27.0 g mean weight). One application of corn distiller's solubles (equivalent to approx. 2000 ppM) and three applications of corn distiller's mash (approx. 5 kg/application) were made over the course of the yield trails (approx. 120 days). No other food or fertilizer was added to the ponds. Survival of shrimp ranged from 34 to 75%. Survival of brood fish exceeded 90%. Mean weight of shrimp at harvest was approximately 12 g, and average production was equivalent to approximately 104 kg ha/sup -1/. Golden shiner reared in the same ponds as shrimp had production rates equivalent to approxmately 130 kg ha/sup -1/. The presence of fish did not appear to impede shrimp production. Although production results of fish and shrimp were encouraging, several factors existed which impeded production; these included: (1) little by-product was applied to ponds because the distillery was undergoing its shakedown period; (2) ponds were new and had minimal natural productivity; (3) grass was not fully established on the watershed and ponds became turbid; and (4) lower than normal temperatures prevailed over much of the growing period. 11 references, 2 figures, 8 tables.

Kohler, C.C.; Lewis, W.M.; Krueger, S.P.

1983-01-01

70

Induction of humoral and cell-mediated immune responses by hepatitis B virus epitope displayed on the virus-like particles of prawn nodavirus.  

PubMed

Hepatitis B virus (HBV) is a deadly pathogen that has killed countless people worldwide. Saccharomyces cerevisiae-derived HBV vaccines based upon hepatitis B surface antigen (HBsAg) is highly effective. However, the emergence of vaccine escape mutants due to mutations on the HBsAg and polymerase genes has produced a continuous need for the development of new HBV vaccines. In this study, the "a" determinant within HBsAg was displayed on the recombinant capsid protein of Macrobrachium rosenbergii nodavirus (MrNV), which can be purified easily in a single step through immobilized metal affinity chromatography (IMAC). The purified protein self-assembled into virus-like particles (VLPs) when observed under a transmission electron microscope (TEM). Immunization of BALB/c mice with this chimeric protein induced specific antibodies against the "a" determinant. In addition, it induced significantly more natural killer and cytotoxic T cells, as well as an increase in interferon gamma (IFN-?) secretion, which are vital for virus clearance. Collectively, these findings demonstrated that the MrNV capsid protein is a potential carrier for the HBV "a" determinant, which can be further extended to display other foreign epitopes. This paper is the first to report the application of MrNV VLPs as a novel platform to display foreign epitopes. PMID:25416760

Yong, Chean Yeah; Yeap, Swee Keong; Goh, Zee Hong; Ho, Kok Lian; Omar, Abdul Rahman; Tan, Wen Siang

2015-02-01

71

Ozone treatment in a closed culture system for Macrobrachium rosenbergii  

E-print Network

, taste and turbidity are affected by oxidation of organic snd inorganic impurities. Such properties of ozone suggested its application in the maintenance of acceptable quality in the recirculated water of closed culture systems. The use of ozone in a... changes during ozonation, such a test was run in this study using culture media prepared from deionized water and from dechlorinated tap water. The dechlorinated tap water was prepared with addition of thiosulfate and aeration. The salinity of both...

Yamaguchi, Ryoji

2012-06-07

72

Structural characterization of the lipovitellin from the shrimp Macrobrachium borellii.  

PubMed

In oviparous species, proteins and lipids are found in the vitellus forming lipoproteins called lipovitellins. They are an important energy source for embryos development and larvae growth and survival. We have previously isolated and partially characterized the sole egg cytosolic lipovitellin from the freshwater shrimp Macrobrachium borellii. It is a native protein of 440 kDa, composed of two subunits of 94 and 112 kDa. In the present work we studied size, shape and structure of M. borellii lipovitellin using electron microscopy, crosslinking reagents, MALDI-TOF, circular dichroism, fluorescence and partial proteolysis. The results showed that lipovitellin has a quasi spherical morphology with an estimated diameter of 18.5+/-3.5 nm. It appears to be composed of two subunits of 94 kDa, and one of 112 kDa. The larger subunit is more susceptible to trypsinolysis, indicating that it is less compactly folded and/or more exposed to the aqueous medium than the 94 kDa subunits. The hetero-trimer is held together by non-covalent interactions. Peptide mass fingerprinting by MALDI-TOF, produced 42 polypeptides matching to a vitellogenin of a related species (Macrobrachium rosenbergii). Circular dichroism indicated that this protein contains 35.7% alpha-helix, 16.6% beta-sheet and 20% turns. Tryptophan fluorescence emission, at a maximum of 334 nm, indicated that the environment polarity of these aromatic residues is similar to that of other crustacean lipoproteins. PMID:17030141

Garcia, C F; Cunningham, M; Soulages, J L; Garda, H A; Pollero, R

2006-01-01

73

Virus-Like Particles of a Fish Nodavirus Display a Capsid Subunit Domain Organization Different from That of Insect Nodaviruses  

Microsoft Academic Search

The structure of recombinant virus-like particles of malabaricus grouper nervous necrosis virus (MGNNV), a fish nodavirus isolated from the grouper Epinephelus malabaricus, was determined by electron cryomicroscopy (cryoEM) and three-dimensional reconstruction at 23-Å resolution. The cryoEM structure, sequence compar- ison, and protein fold recognition analysis indicate that the coat protein of MGNNV has two domains resembling those of tomato bushy

Liang Tang; Chan-Shing Lin; Neel K. Krishna; Mark Yeager; Anette Schneemann; John E. Johnson

2002-01-01

74

Toxicity of ammonia to larvae of the freshwater shrimp, Macrobrachium rosenbergii  

E-print Network

population even after a pro- longed period of exposure) reported for fish range from 0. 25-0. 41 mg/I NH -N (Lloyd, 1961) Ball, 1967; Lloyd and Orr, 1969; Burkhalter and Kaya, 1977). Rice and Stokes (1975) found. that rain'bow trout eggs and alevins were... highly tolerant of ammonia but at the end of egg yolk absorption, rainbow trout fry increased in susceptibility dramatically. Redner (1978) obtained a 48- h 1050 of 2. 373 mgl'3 IIN3-N fo ~rfla 'a a ea; aft 35-day exposure to ammonia levels which...

Llobrera, Jose Alvarez

1979-01-01

75

Abundance and diversity of zooplankton in semi intensive prawn (Macrobrachium rosenbergii) farm.  

PubMed

The present study was carried out on the seasonal abundance and diversity of zooplankton in a semi- intensive prawn farm of Bagerhat district from July to December, 2008. Plankton samples were collected by conical shaped monofilament nylon net (Plankton net) and Lugol's solution was used for preservation. The zooplankton abundance was influenced by physico-chemical factors. During the study period 11 genera of zooplankton under 5 orders were recorded from the study ponds namely Copepoda, Rotifera, Cladocera, Ostracoda and Crustacean Larvae. Among all groups copepod was the dominant order. The percentages of Copepoda, Rotifera, Cladocera, Ostracoda and Crustacean Larvae in semi-intensive culture system were 54%, 28%, 12%, 4% and 2% respectively. But the genera Brachionus under the order of Rotifer was dominant among all other genera. Cyclops and Helidiaptomus under the order of Copepod were the 2nd dominant genera. Numbers of zooplankton species were recorded to be the highest in summer season and minimum at early winter season. Highest number of zooplankton found at the month of October. Total zooplankton shows significant positive relationship with water temperature ((r?=?+0.384), Dissolve Oxygen(r?=?+0.113), pH(r?=?+0.320), Free CO2 (r?=?+0.319), Alkalinity(r?=?+0.269), Hardness (r?=?+0.402) and negative relationship with Salinity(r?=?-0.486), Transparency(r?=?-0.693). The findings of the present study will help to improve the management strategies of shrimp culture system. PMID:23667823

Shil, Jadobendro; Ghosh, Alokesh Kumar; Rahaman, S M Bazlur

2013-12-01

76

Antimicrobial activity of chitosan against vibrios from freshwater prawn Macrobrachium rosenbergii larval rearing systems.  

PubMed

Chitosan is a biocompatible and biodegradable natural polymer with established antimicrobial properties against specific microorganisms. The present study demonstrates its antibacterial activity against 48 isolates of Vibrio species from prawn larval rearing systems. The antibacterial activity had a positive correlation with the concentration of chitosan. This work opens up avenues for using chitosan as a prophylactic biopolymer for protecting prawn larvae from vibriosis. PMID:16385825

Anas, A; Paul, S; Jayaprakash, N S; Philip, R; Bright Singh, I S

2005-11-01

77

Fecundity and fertility of Macrobrachium amazonicum (Crustacea, Palaemonidae).  

PubMed

In Brazil, studies with native freshwater prawn species were discontinued due to great importance of Macrobrachium rosenbergii. Therefore, it is necessary to continue investigations about our species, in order to develop technology adequate to our reality and in a future allow prawn farmers to culture other species. The aim of this study was to determine the fecundity and fertility of Macrobrachium amazonicum captured monthly from June 1999 to June 2001 from Jaguaribe River, Itaiçaba, Ceará, Brazil. Prawns were collected using fishing net and transferred at Biological Science Laboratory, Ceara State University (Fortaleza, Ceará, Brazil). Among the ovigerous M. amazonicum females, 60 were randomly selected to determine fecundity. The eggs adhered to the pleopods were taken out and they were then placed in a Gilson solution, and then stored in alcohol 70%. Individual fecundity was determined from the total egg counting, using a stereoscopic microscope. To determine fertility, ovigerous M. amazonicum females were stored in individual 10 L-glass tanks maintained under strong aeration. After the hatching, the larvae were siphoned and counted. The data referring to total length and weight of all the females, storage date, coloration and number of eggs, weight and coloration of gonad and number of hatched larvae were noted. With respect to average fecundity (F) by length classes, the lowest and highest number of eggs observed was 696 and 1,554, respectively. As for fecundity by weight classes, the lowest number of eggs observed was 760 and the highest, 1,690. The highest number of eggs observed individually per hatching was 2,193. Average fecundity/total length (L) and average fecundity/total weight (W) may be expressed by a linear relationship. The adjusted equations are: F = -411.6 + 203.1 L (p < 0.0001) and F = 566.4 + 157.3 W (p < 0.0001), respectively. In the analysis of average fertility (N) per length classes, the lowest and highest number of larvae observed was 374 and 1,301, respectively. With respect to fertility per weight classes, the lowest number of larvae was 581 and the highest, 1,391. In this work, the maximum number of larvae observed per hatching for females kept in laboratory was 2,594. Average fertility/total length and average fertility/total weight may be expressed by a linear relationship. The adjusted equations are: N = -1042.7 + 264.9 L (p < 0.0002); N = 384.1 + 160.3 W (p < 0.003). From these results we can deduced that fecundity and fertility of M. amazonicum are lower than ones commercial species, never-the-less it can be captured during all year long. The number of captured prawns was large in the months whose level of water was low; the inverse was observed in the months that the river was with a high volume of water. PMID:15622846

Da Silva, R R; Sampaio, C M S; Santos, J A

2004-08-01

78

Screening of parasitic and IHHNV infections in wild giant freshwater prawn Macrobrachium rosenbergii from Rejang River at Kuching, Sarawak.  

PubMed

A preliminary survey of parasitic and infectious hypodermal and haematopoietic necrosis virus (IHHNV) infections in giant freshwater prawn from the Damak Sea of Rejang River, Kuching, Sarawak was conducted. Symptoms of black spots/patches on the rostrum, carapace, pleopods or telson were observed in most of the 107 samples collected. Parasitic examination revealed sessiline peritrichs such as (Zoothamnium sp.), nematode larvae, gregarine stage and cocoon of leech with prevalences of 1.2%, 1.2%, 5% and 17% respectively. Under histopathological examination, changes like accumulation of hemocytes around hepatopancreatic tubules due to vibriosis, basophilic intranuclear inclusions in the epithelium and E-cell of hepatopancreatic tubules as a result of HPV were seen through the section. No positive infection of IHHNV was detected in 78 samples. As such, the wild giant freshwater prawns in Damak Sea of Rejang River in Kuching are IHHNV-free though infections of parvo-like virus and bacteria were seen in histopathology. PMID:21602773

Kua, Beng Chu; Choong, F C; Hazreen Nita, M K; Muhd Faizul H, A H; Bhassu, S; Imelda, R R; Mohammed, M

2011-04-01

79

The microbial flora of pond-reared shrimp (Penaeus stylirostris, P. setiferus, P. vannamei, and Macrobrachium rosenbergii)  

E-print Network

) in the pond waters. Samples of P. setiferus and Macr btachdcm ~reenb 11 mere obtained f o pr feet lo- cations on the Pecos and. Rio Grande Rivers. Aerobic plate counts of fresh shrimp ranged from 1. 5 X 10 ? 2. 9 X 10 per gram. Coryneform bacteria... stored on ice for 1V eight days ranged from 5. 1-9. 4 X 10 . The microbial flora 2 of stored shrimp was dominated by coryneform bacteria, Pseudomonas, and Nicrococcus species. The aerobic plate counts of pond waters ranged from 6. 1 X 10 ? 2. 2 X 10...

Christopher, Frank Mitchell

1976-01-01

80

Molecular perspective on the American transisthmian species of Macrobrachium (Caridea, Palaemonidae)  

PubMed Central

Abstract The closure of the Isthmus of Panama (about 3.1 million years ago) separated previously continuous populations and created two groups of extant species, which live now in the Pacific and Atlantic drainage systems. This relatively recent event was a trigger to diversification of various species in the Neotropics, nonetheless there are exemplars that do not show sufficient morphologic variability to separate them by traditional morphological tools. About 60 years ago, some freshwater decapod species with high morphological similarity were separate by previous researchers, based on geographical distribution, in Pacific and Atlantic and considered as “sister species”. However, the complete isolation of these prawns by this geographical barrier is questionable, and it has generated doubts about the status of the following transisthmian pairs of sibling species: Macrobrachium occidentale × Macrobrachium heterochirus, Macrobrachium americanum × Macrobrachium carcinus, Macrobrachium digueti × Macrobrachium olfersii, Macrobrachium hancocki × Macrobrachium crenulatum, Macrobrachium tenellum × Macrobrachium acanthurus and Macrobrachium panamense × Macrobrachium amazonicum. Here we evaluated the relation among these pairs of sibling species in a molecular phylogenetic context. We generated 95 new sequences: 26 sequences of 16S rDNA, 25 of COI mtDNA and 44 of 18S nDNA. In total, 181 sequences were analyzed by maximum likelihood phylogenetic method, including 12 Macrobrachium transisthmian species, as well as seven other American Macrobrachium species, and two other palaemonids. Our analysis corroborated the morphological proximity of the sibling species. Despite the high degree of morphological similarities and considerable genetic diversification encountered among the transisthmian sister species, our data support the conclusion that all species included in sibling groups studied herein are valid taxonomic entities, but not all pairs of siblings form natural groups. PMID:25561833

Pileggi, Leonardo G.; Rossi, Natália; Wehrtmann, Ingo S.; Mantelatto, Fernando L.

2014-01-01

81

Feeding habit of the Amazon river prawn Macrobrachium amazonicum larvae  

Microsoft Academic Search

To investigate the feeding habit of Macrobrachium amazonicum, three experiments were carried out assessing the stage at which larvae start exogenous feeding, the acceptance of inert food by different larval stages and the ratio between live and inert diet ingested by larvae at each larval stage. In the first experiment, newly hatched larvae were kept in 500-mL beakers and fed

Mariana Cutolo de Araujo; Wagner Cotroni Valenti

2007-01-01

82

Crystallization and preliminary crystallographic analysis of a viral RNA-silencing suppressor encoded by Wuhan nodavirus.  

PubMed

Wuhan nodavirus (WhNV), which is a new member of the Nodaviridae family, encodes a viral protein, B2, that suppresses RNA silencing and host-cell RNA interference (RNAi)-mediated immunity. Although Flock House virus (FHV), another member of the Nodaviridae family, also produces a B2 protein with a similar function, the primary sequences of the B2 proteins from WhNV and FHV have no similarity. To gain a better understanding of the structural details and the mechanism of suppression of RNA silencing by WhNV B2 and to compare it with FHV B2, recombinant WhNV B2 protein has been overexpressed in Escherichia coli, purified and crystallized at 291?K using PEG 4000 as a precipitant. A 2.8?Å resolution data set has been collected from a single crystal at 100?K. This crystal belonged to space group P2?2?2?, with unit-cell parameters a=27.3, b=45.6, c=133.9?Å, ?=?=?=90°. Assuming the presence of two molecules in the asymmetric unit, the Matthews coefficient is 2.2?Å3?Da(-1). PMID:24100569

Liu, Yuanyuan; Zhao, Yuhui; Zhang, Yong; Chen, Hui

2013-10-01

83

Genome-Wide Analysis of Host Factors in Nodavirus RNA Replication  

PubMed Central

Flock House virus (FHV), the best studied of the animal nodaviruses, has been used as a model for positive-strand RNA virus research. As one approach to identify host genes that affect FHV RNA replication, we performed a genome-wide analysis using a yeast single gene deletion library and a modified, reporter gene-expressing FHV derivative. A total of 4,491 yeast deletion mutants were tested for their ability to support FHV replication. Candidates for host genes modulating FHV replication were selected based on the initial genome-wide reporter gene assay and validated in repeated Northern blot assays for their ability to support wild type FHV RNA1 replication. Overall, 65 deletion strains were confirmed to show significant changes in the replication of both FHV genomic RNA1 and sub-genomic RNA3 with a false discovery rate of 5%. Among them, eight genes support FHV replication, since their deletion significantly reduced viral RNA accumulation, while 57 genes limit FHV replication, since their deletion increased FHV RNA accumulation. Of the gene products implicated in affecting FHV replication, three are localized to mitochondria, where FHV RNA replication occurs, 16 normally reside in the nucleus and may have indirect roles in FHV replication, and the remaining 46 are in the cytoplasm, with functions enriched in translation, RNA processing and trafficking. PMID:24752411

Hao, Linhui; Lindenbach, Brett; Wang, Xiaofeng; Dye, Billy; Kushner, David; He, Qiuling; Newton, Michael; Ahlquist, Paul

2014-01-01

84

The Self-Interaction of a Nodavirus Replicase Is Enhanced by Mitochondrial Membrane Lipids  

PubMed Central

RNA replication of positive-strand (+)RNA viruses requires the protein-protein interactions among viral replicases and the association of viral replicases with intracellular membranes. Protein A from Wuhan nodavirus (WhNV), which closely associate with mitochondrial membranes, is the sole replicase required for viral RNA replication. Here, we studied the direct effects of mitochondrial membrane lipids (MMLs) on WhNV protein A activity in vitro. Our investigations revealed the self-interaction of WhNV protein A is accomplished via two different patterns (i.e., homotypic and heterotypic self-interactions via different interfaces). MMLs stimulated the protein A self-interaction, and this stimulation exhibited selectivity for specific phospholipids. Moreover, we found that specific phospholipids differently favor the two self-interaction patterns. Furthermore, manipulating specific phospholipid metabolism affected protein A self-interaction and the activity of protein A to replicate RNA in cells. Taken together, our findings reveal the direct effects of membrane lipids on a nodaviral RNA replicase. PMID:24586921

Qiu, Yang; Wang, Zhaowei; Liu, Yongxiang; Han, Yajuan; Miao, Meng; Qi, Nan; Yang, Jie; Xia, Hongjie; Li, Xiaofeng; Qin, Cheng-Feng; Hu, Yuanyang; Zhou, Xi

2014-01-01

85

Effects of hot-water extract of banana (Musa acuminata) fruit's peel on the antibacterial activity, and anti-hypothermal stress, immune responses and disease resistance of the giant freshwater prawn, Macrobrachium rosenbegii.  

PubMed

The hot-extracts isolated from fruit's peel of banana, Musa acuminata, was evaluated on the antibacterial activity to pathogens from aquatic animals, and immunostimulating potential, disease resistance and anti-hypothermal stress in giant freshwater prawn, Macrobrachium rosenbergii through injection administration. The banana peel extract (BPE) showed good activity against 1 Gram-positive and 3 Gram-negative pathogens, including Lactococcus garvieae, Photobacteria damsella, Vibrio alginolyticus and Vibrio parahemolyticus especially in prawn pathogen of L. garvieae strain, which were carried out by a disk diffusion method. Prawn received BPE via injection administration at 1-6 ?g (g prawn)(-1) significantly increased total haemocyte count (THC), hyaline cell (HC), granular cell (GC), phenoloxidase (PO) activity and phagocytic activity against L. garvieae from 3 to 6 days, and significantly increased clearance efficiency against L. garvieae and a significantly decreased coagulation time of prawn from 1 to 6 days. Prawn injected with BPE at 6.0 ?g (g prawn)(-1) for 6 days showed significantly increased superoxide dismutase (SOD) activity, but significantly decreased respiratory bursts (RBs) of per haemocyte. Survival rates of M. rosenbergii injected with BPE at concentrations of 1, 3 and 6 ?g (g prawn)(-1) were significantly higher than those injected with saline control after challenge with L. garvieae for 4-6 days, and the respective relative survival percentages of prawn were 28.6%, 38.1%, and 47.8%, respectively at 6 days. The sublethal time of prawns that had received saline and BPE at 1, 3 and 6 ?g (g prawn)(-1) for 6 days and then were transferred from 28 °C to 14 °C were 69.4, 79.8, 83.6, and 90.2 h, respectively. It was concluded that the BPE can be used as the bacteriostat, and immunostimulant and physiological regulator for prawn through injection administration to enhance immunity, physiological responses, and resistance against L. garvieae. PMID:24906123

Rattanavichai, Wutti; Cheng, Winton

2014-08-01

86

Regulation of laboratory populations of snails (Biomphalaria and Bulinus spp.) by river prawns, Macrobrachium spp. (Decapoda, Palaemonidae): implications for control of schistosomiasis.  

PubMed

Human schistosomiasis is a common parasitic disease endemic in many tropical and subtropical countries. One barrier to achieving long-term control of this disease has been re-infection of treated patients when they swim, bathe, or wade in surface fresh water infested with snails that harbor and release larval parasites. Because some snail species are obligate intermediate hosts of schistosome parasites, removing snails may reduce parasitic larvae in the water, reducing re-infection risk. Here, we evaluate the potential for snail control by predatory freshwater prawns, Macrobrachium rosenbergii and M. vollenhovenii, native to Asia and Africa, respectively. Both prawn species are high value, protein-rich human food commodities, suggesting their cultivation may be beneficial in resource-poor settings where few other disease control options exist. In a series of predation trials in laboratory aquaria, we found both species to be voracious predators of schistosome-susceptible snails, hatchlings, and eggs, even in the presence of alternative food, with sustained average consumption rates of 12% of their body weight per day. Prawns showed a weak preference for Bulinus truncatus over Biomphalaria glabrata snails. Consumption rates were highly predictable based on the ratio of prawn: snail body mass, suggesting satiation-limited predation. Even the smallest prawns tested (0.5-2g) caused snail recruitment failure, despite high snail fecundity. With the World Health Organization turning attention toward schistosomiasis elimination, native prawn cultivation may be a viable snail control strategy that offers a win-win for public health and economic development. PMID:24388955

Sokolow, Susanne H; Lafferty, Kevin D; Kuris, Armand M

2014-04-01

87

Functional analysis of an orange-spotted grouper (Epinephelus coioides) interferon gene and characterisation of its expression in response to nodavirus infection.  

PubMed

We cloned and sequenced 2C I-IFN, a two-cysteine containing type I interferon (I-IFN) gene, in orange-spotted grouper (Epinephelus coioides). The cDNA has 769 base pairs, the protein has 172 amino acids, and the predicted signal peptide has 18 amino acids with two cysteines. This gene is similar to I-FNs from sea bass and other teleosts. 2C I-IFN has 5 exons and 4 introns, also similar to other teleost I-IFNs. Immunohistochemical (IHC) analysis indicated that expression is predominantly membrane-localized in healthy grouper, but has a zonal distribution in nodavirus-infected grouper. Grouper infected with nodavirus had elevated levels of 2C I-IFN at 72 h and Mx at days 6-7. Recombinant 2C I-IFN activated grouper Mx, leading to upregulated antiviral activity. The grouper Mx promoter was highly induced after treatment with recombinant 2C I-IFN. The present results suggest that expression of grouper 2C I-IFN may participate in the immunologic barrier function against nodavirus. PMID:24731841

Chen, Young-Mao; Kuo, Cham-En; Chen, Guan-Ru; Kao, Yu-Ting; Zou, Jun; Secombes, Chris J; Chen, Tzong-Yueh

2014-10-01

88

Genetic variability and phylogenetic aspects in species of the genus Macrobrachium.  

PubMed

The genus Macrobrachium includes prawns, which are widely distributed in lakes, floodplains, and rivers in tropical and subtropical regions of South America. This genus presents nearly 210 known species with great ecological and economic importance. However, few studies are related to the biology of these crustaceans. In this study, we analyzed the genetic variability and phylogenetic relationship between Macrobrachium amazonicum and Macrobrachium jelskii, which are closely related species. Additionally, they are syntopics and their taxonomy poses problems because it is difficult to differentiate between the species. We used the mitochondrial gene sequences COI and 16S rRNA to assess the genetic structure of these species in 3 populations that were collected from Tiete hydrographic basin (São Paulo State, Brazil). The interspecific comparison of samples that were collected at the same and different locations showed a low rate of genetic variability. This similarity was attributed to the recent introduction of these species in the regions that were sampled and the habitat conditions in which they inhabit. In addition, these results may be consistent with the hypothesis that they are a single species, interspecific hybrids, or metapopulation. The dendrogram analyses did not reveal the formation of clusters, confirming the disturbances in the genetic structure of the samples that were analyzed in this study. These data are pioneers to these crustaceans, and they confirm the ecological and evolutionary problems between these Macrobrachium species. PMID:24854444

Guerra, A L; Lima, A V B; Lucato Júnior, R V; Chiachio, M C; Taddei, F G; Castiglioni, L

2014-01-01

89

Population dynamics of Niger River prawn (Macrobrachium felicinum) in Lower Taylor Creek, Niger Delta, Nigeria  

Microsoft Academic Search

The population dynamics of Macrobrachium felicinum (Holthuis, 1949) in Lower Taylor Creek, Niger Delta, Nigeria, was analysed using monthly length-frequency data (June 2008 – May 2010). This study was aimed at determining the status of fishery and establishing the levels of exploitation that will give sustainable yields. The FAO-ICLARM stock assessment tool (FISAT II) software was used to estimate population

T onbarapagha Kingdom; Aduabobo Ibitoruh Hart

2012-01-01

90

Cortney L. Ohs, PhD Select Publications Cassiano, E.J., C.L. Ohs, C.R. Weirich, N.E. Breen, and A.L. Rhyne. 2011. Evaluation of larval  

E-print Network

.L. Ohs, and B.D. Petty. 2010. Evaluation of a point-of-care blood analyzer for use in determination of dietary administration of 17alpha - methyltestosterone to freshwater prawn Macrobrachium rosenbergii of freshwater prawn Macrobrachium rosenbergii through dietary administration of dopamine hydrochloride. Journal

Hill, Jeffrey E.

91

Molecular cloning and functional analysis of an orange-spotted grouper (Epinephelus coioides) secreted protein acidic and rich in cysteine (SPARC) and characterization of its expression response to nodavirus.  

PubMed

Mammalian secreted protein acidic and rich in cysteine (SPARC) is the primary regulator of cell shape and cell adhesion to fibronectin. We, for the first time, report the complete sequencing of SPARC cDNA from orange-spotted grouper. Despite the difference in the lengths of the SPARC transcripts, all of the SPARC molecules encoded a signal peptide, follistain-like copper binding sequence (KGHK) domain, and extracellular domain. The grouper SPARC gene was differentially expressed in vivo and contributed differently to high-level expression of SPARC in muscle. Immunohistochemical staining demonstrated a decreased level of SPARC in nodavirus-infected grouper compared with healthy grouper. Comparative real-time polymerase chain reaction analyses of eye tissues of viral nervous necrosis grouper and healthy grouper were performed. Recombinant SPARC produced changes in grouper cell shape 24 h after treatment. The results provide new insight into the pathogenesis of nodavirus, and demonstrate an experimental rationale for SPARC characterization in nodavirus-infected grouper. PMID:21609765

Chen, Young-Mao; Kuo, Cham-En; Huang, Yi-Ling; Shie, Pei-Shiuan; Liao, Jhong-Jian; Yang, Yuan-Chih; Chen, Tzong-Yueh

2011-08-01

92

Immunological-based assays for specific detection of shrimp viruses  

PubMed Central

Among shrimp viral pathogens, white spot syndrome virus (WSSV) and yellow head virus (YHV) are the most lethal agents, causing serious problems for both the whiteleg shrimp, Penaeus (Litopenaeus) vannamei, and the black tiger shrimp, Penaeus (Penaeus) monodon. Another important virus that infects P. vannamei is infectious myonecrosis virus (IMNV), which induces the white discoloration of affected muscle. In the cases of taura syndrome virus and Penaeus stylirostris densovirus (PstDNV; formerly known as infectious hypodermal and hematopoietic necrosis virus), their impacts were greatly diminished after the introduction of tolerant stocks of P. vannamei. Less important viruses are Penaeus monodon densovirus (PmDNV; formerly called hepatopancreatic parvovirus), and Penaeus monodon nucleopolyhedrovirus (PemoNPV; previously called monodon baculovirus). For freshwater prawn, Macrobrachium rosenbergii nodavirus and extra small virus are considered important viral pathogens. Monoclonal antibodies (MAbs) specific to the shrimp viruses described above have been generated and used as an alternative tool in various immunoassays such as enzyme-linked immunosorbent assay, dot blotting, Western blotting and immunohistochemistry. Some of these MAbs were further developed into immunochromatographic strip tests for the detection of WSSV, YHV, IMNV and PemoNPV and into a dual strip test for the simultaneous detection of WSSV/YHV. The strip test has the advantages of speed, as the result can be obtained within 15 min, and simplicity, as laboratory equipment and specialized skills are not required. Therefore, strip tests can be used by shrimp farmers for the pond-side monitoring of viral infection. PMID:24567913

Chaivisuthangkura, Parin; Longyant, Siwaporn; Sithigorngul, Paisarn

2014-01-01

93

Immunological-based assays for specific detection of shrimp viruses.  

PubMed

Among shrimp viral pathogens, white spot syndrome virus (WSSV) and yellow head virus (YHV) are the most lethal agents, causing serious problems for both the whiteleg shrimp, Penaeus (Litopenaeus) vannamei, and the black tiger shrimp, Penaeus (Penaeus) monodon. Another important virus that infects P. vannamei is infectious myonecrosis virus (IMNV), which induces the white discoloration of affected muscle. In the cases of taura syndrome virus and Penaeus stylirostris densovirus (PstDNV; formerly known as infectious hypodermal and hematopoietic necrosis virus), their impacts were greatly diminished after the introduction of tolerant stocks of P. vannamei. Less important viruses are Penaeus monodon densovirus (PmDNV; formerly called hepatopancreatic parvovirus), and Penaeus monodon nucleopolyhedrovirus (PemoNPV; previously called monodon baculovirus). For freshwater prawn, Macrobrachium rosenbergii nodavirus and extra small virus are considered important viral pathogens. Monoclonal antibodies (MAbs) specific to the shrimp viruses described above have been generated and used as an alternative tool in various immunoassays such as enzyme-linked immunosorbent assay, dot blotting, Western blotting and immunohistochemistry. Some of these MAbs were further developed into immunochromatographic strip tests for the detection of WSSV, YHV, IMNV and PemoNPV and into a dual strip test for the simultaneous detection of WSSV/YHV. The strip test has the advantages of speed, as the result can be obtained within 15 min, and simplicity, as laboratory equipment and specialized skills are not required. Therefore, strip tests can be used by shrimp farmers for the pond-side monitoring of viral infection. PMID:24567913

Chaivisuthangkura, Parin; Longyant, Siwaporn; Sithigorngul, Paisarn

2014-02-12

94

Sub-lethal impact of carbaryl on food utilization in the freshwater prawn Macrobrachium malcolmsonii.  

PubMed

This study determines the toxic effect of carbaryl (Sevin50% W.P) on the food utilization parameters in intermoult juveniles of the prawn, Macrobrachium malcolmsonii. The prawns (4.5-5.0 cm in length and 1.0-1.25 g wet wt.) were exposed to three sub-lethal concentrations of carbaryl (5.15, 7.73 and 15.47 microgl-1) for duration of 40 days. The toxic medium was renewed daily. The prawns were fed ad libitum with known energy quantity of boiled goat liver on daily basis. The overall wet weight gain was calculated. The energy lost through unconsumed food (15-60%), faeces (15-109%), ammonia excretion (9-27%) and moults (13-26%) of the prawns were calculated. The feeding rate, the rate and efficiency of absorption, the metabolic and food conversion rates and the gross and net food conversions efficiencies were found to be significantly declined (p<0.05) in test prawns when compared to that of the control. The energy lost through faeces, ammonia excretion and exuvia was found to be significantly elevated (p<0.05) in test prawns than that of the control. The effectof carbaryl on the bioenergetics parameters was severe in the highest sub-lethal concentration, less in the intermediate concentration and least in the lowest sub-lethal concentration. The results indicated that decrease in feeding, absorption, metabolism and food conversion are interdependent and toxicity of carbaryl diverting energy from production to maintenance pathways, which ultimately resulting in declined growth of M. malcolmsonii. PMID:22167951

Bhavan, P Saravana; Geraldine, P; Sowdeswari, R

2011-05-01

95

Toxicity of cryoprotectants agents in freshwater prawn embryos of Macrobrachium amazonicum.  

PubMed

Summary The process of cooling and cryopreservation of prawn embryos is a viable alternative for a continuous supply of larvae for freshwater prawn farming ponds. However, studies involving the application of those techniques as well as on toxicity of cryoprotectants in freshwater prawn embryos are scarce. Thus, this study aims to test the toxicity of methylic alcohol (MET), dimethyl sulfoxide (DMSO) and ethylene glycol (EG) on Macrobrachium amazonicum embryos. For the present experiment, pools of embryos were taken from 15 M. amazonicum females and were divided into three groups and tested in duplicate at concentrations of 10, 5, 3; 1, 0.5 or 0.1%. Toxicity tests were conducted for 24 h in Falcon® pipes to obtain the lethal concentration for 50% of the larvae (LC50). After the set period for testing, random samples of embryos were removed for morphological analysis under stereoscopic microscopes. Results were analysed using analysis of variance (ANOVA) and Tukey's test at a 5% significance level and Trimmed Spearman-Karber Analysis to determine LC50-24 h. DMSO toxicity tests revealed that 5% and 10% concentrations showed the highest toxicity and differed from the control (P ? 0.05), 24h-LC50 was 437.4 ± 14.4 µL. MET was less toxic among the tested cryoprotectants and concentrations did not allow the determination of its LC50-24h. For tests with EG, concentrations of 3, 5 or 10% solutions resulted in a 100% mortality to tested embryos; EG was the tested cryoprotectant with the highest toxicity, with an LC50-24h average of 81.91 ± 35.3 µl. PMID:25255785

Ferreira, Arthur Vinícius Lourenço; Castro, Elias José Teles; Barbosa, Mariana Silva Alves; de Sousa, Míriam Luzia Nogueira Martins; de Araújo Neto, Manoel Paiva; Filho, Aldeney Andrade Soares; de Souza Sampaio, Celia Maria

2014-09-26

96

Temporal trends of organochlorine pesticides in prawn (Macrobrachium nipponense) from Lake Kasumigaura, Japan, during 1978-2000.  

PubMed

Temporal trends of organochlorine pesticides such as beta-hexachlorocyclohexane (beta-HCH), hexachlorobenzene (HCB), and 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene (p,p'-DDE), were determined in freshwater prawn (Macrobrachium nipponense) collected from Lake Kasumigaura in 1978 to 2000. The organochlorine pesticides elucidated a 72.4% decrease in beta-HCH, from 42 (1978) to 11.6 ng/g fat (2000); an 89.6% decrease in HCB, from 1.64 (1978) to 0.17 ng/g fat (2000); and an 87.3% decrease in p,p'-DDE, from 97.5 (1978) to 12.4 ng/g fat (1992). After organochlorine pesticide prohibition in 1971, the declining trend of beta-HCH, HCB, and p,p'-DDE concentrations persisting in the prawns could be approximated by exponential equations. PMID:15346782

Sunardi; Kumar, K Senthil; Masunaga, S; Iseki, N; Kasuga, S; Nakanishi, J

2004-07-01

97

Vacuolating encephalopathy and retinopathy associated with a nodavirus-like agent: a probable cause of mass mortality of wild Golden grey mullet (Liza aurata) and Sharpnose grey mullet (Liza saliens) in Iranian waters of the Caspian Sea.  

PubMed

Mullets are dominant fishes in the catch composition in the southern coasts of the Caspian Sea and after (Rutilus frisii kutum Kamensky, 1901) have a worthy role in production of marine proteins and incomings of north provinces of Iran. Mullets stocks decreased dramatically in recent decades in the Caspian Sea and catch amount reached from 6446 MT on 2002 to 2151 MT in 2012. Mysterious mortalities occurred in wild mullet (Liza auratu) and (Liza saliens) in Iranian waters of Caspian Sea in recent years. Regarding to investigation of causative agent of mentioned outbreak about 322 suspected samples were collected from coastal capture sites of Iranian north provinces in 2008 till 2011. Moribund fish revealed skin darkening, erratic swimming, belly-up at rest and high distension of swim bladder. Target tissues such as brain and eye were removed and then fixed for histopathology and TEM assay. Widespread and massive vacuolation were observed in brain, spinal cord, retina and optical nerve and intracytoplasmic vacuoles and virus particles in retina. So concerning to clinical signs, histopathological and TEM findings, it could be concluded that nodavirus-like agent could be probable cause of mass mortality of wild mullet in Iranian waters of the Caspian Sea. PMID:25674618

Zorriehzahra, Mohammad Jalil; Nazari, Alireza; Ghasemi, Mohaddes; Ghiasi, Maryam; Karsidani, Somayeh Haghighi; Bovo, Giuseppe; Daud, Hassan Hj Mohd

2014-12-01

98

Growth and mortality, recruitment and yield of the fresh-water shrimp, Macrobrachium völlenhovenii, Herklots 1851 (Crustacea, Palaemonidae) in the Fahe reservoir, Côte d'Ivoire, West Africa  

Microsoft Academic Search

We studied the growth, mortality rates and recruitment pattern of an exploited fresh-water shrimp (Macrobrachium völlenhovenii) population in the Fahe reservoir of the San-Pedro River, Côte d'Ivoire using 12 consecutive months (January to December 1995) length–frequency samples and FISAT software (which incorporates both the ELEFAN and LSFA programs). A fit of the seasonalized von Bertalanffy growth equation to the length–frequency

Lawrence Etim; Yacouba Sankare

1998-01-01

99

Molecular Analysis of the Freshwater Prawn Macrobrachium olfersii (Decapoda, Palaemonidae) Supports the Existence of a Single Species throughout Its Distribution  

PubMed Central

Macrobrachium olfersii is an amphidromous freshwater prawn, widespread along the eastern coasts of the Americas. This species shows great morphological modifications during ontogenesis, and several studies have verified the existence of a wide intraspecific variation. Because of this condition, the species is often misidentified, and several synonyms have been documented. To elucidate these aspects, individuals of M. olfersii from different populations along its range of distribution were investigated. The taxonomic limit was established, and the degree of genetic variability of this species was described. We extracted DNA from 53 specimens of M. olfersii, M. americanum, M. digueti and M. faustinum, which resulted in 84 new sequences (22 of 16S mtDNA, 45 of Cythocrome Oxidase I (COI) mtDNA, and 17 of Histone (H3) nDNA). Sequences of three genes (single and concatenated) from these species were used in the Maximum Likelihood and Bayesian Inference phylogenetic analyses and COI sequences from M. olfersii were used in population analysis. The genetic variation was evaluated through the alignment of 554 bp from the 16S, 638 bp from the COI, and 338 bp from the H3. The rates of genetic divergence among populations were lower at the intraspecific level. This was confirmed by the haplotype net, which showed a continuous gene flow among populations. Although a wide distribution and high morphological intraspecific variation often suggest the existence of more than one species, genetic similarity of Caribbean and Brazilian populations of M. olfersii supported them as a single species. PMID:23382941

Rossi, Natália; Mantelatto, Fernando Luis

2013-01-01

100

Molecular analysis of the freshwater prawn Macrobrachium olfersii (Decapoda, Palaemonidae) supports the existence of a single species throughout its distribution.  

PubMed

Macrobrachium olfersii is an amphidromous freshwater prawn, widespread along the eastern coasts of the Americas. This species shows great morphological modifications during ontogenesis, and several studies have verified the existence of a wide intraspecific variation. Because of this condition, the species is often misidentified, and several synonyms have been documented. To elucidate these aspects, individuals of M. olfersii from different populations along its range of distribution were investigated. The taxonomic limit was established, and the degree of genetic variability of this species was described. We extracted DNA from 53 specimens of M. olfersii, M. americanum, M. digueti and M. faustinum, which resulted in 84 new sequences (22 of 16S mtDNA, 45 of Cythocrome Oxidase I (COI) mtDNA, and 17 of Histone (H3) nDNA). Sequences of three genes (single and concatenated) from these species were used in the Maximum Likelihood and Bayesian Inference phylogenetic analyses and COI sequences from M. olfersii were used in population analysis. The genetic variation was evaluated through the alignment of 554 bp from the 16S, 638 bp from the COI, and 338 bp from the H3. The rates of genetic divergence among populations were lower at the intraspecific level. This was confirmed by the haplotype net, which showed a continuous gene flow among populations. Although a wide distribution and high morphological intraspecific variation often suggest the existence of more than one species, genetic similarity of Caribbean and Brazilian populations of M. olfersii supported them as a single species. PMID:23382941

Rossi, Natália; Mantelatto, Fernando Luis

2013-01-01

101

Transcriptome Analysis of the Oriental River Prawn, Macrobrachium nipponense Using 454 Pyrosequencing for Discovery of Genes and Markers  

PubMed Central

Background The oriental river prawn, Macrobrachium nipponense, is an economically and nutritionally important species of the Palaemonidae family of decapod crustaceans. To date, the sequencing of its whole genome is unavailable as a non-model organism. Transcriptomic information is also scarce for this species. In this study, we performed de novo transcriptome sequencing to produce the first comprehensive expressed sequence tag (EST) dataset for M. nipponense using high-throughput sequencing technologies. Methodology and Principal Findings Total RNA was isolated from eyestalk, gill, heart, ovary, testis, hepatopancreas, muscle, and embryos at the cleavage, gastrula, nauplius and zoea stages. Equal quantities of RNA from each tissue and stage were pooled to construct a cDNA library. Using 454 pyrosequencing technology, we generated a total of 984,204 high quality reads (338.59Mb) with an average length of 344 bp. Clustering and assembly of these reads produced a non-redundant set of 81,411 unique sequences, comprising 42,551 contigs and 38,860 singletons. All of the unique sequences were involved in the molecular function (30,425), cellular component (44,112) and biological process (67,679) categories by GO analysis. Potential genes and their functions were predicted by KEGG pathway mapping and COG analysis. Based on our sequence analysis and published literature, many putative genes involved in sex determination, including DMRT1, FTZ-F1, FOXL2, FEM1 and other potentially important candidate genes, were identified for the first time in this prawn. Furthermore, 6,689 SSRs and 18,107 high-confidence SNPs were identified in this EST dataset. Conclusions The transcriptome provides an invaluable new data for a functional genomics resource and future biological research in M. nipponense. The molecular markers identified in this study will provide a material basis for future genetic linkage and quantitative trait loci analyses, and will be essential for accelerating aquaculture breeding programs with this species. PMID:22745820

Ma, Keyi; Qiu, Gaofeng; Feng, Jianbin; Li, Jiale

2012-01-01

102

Molecular cloning of two tropomyosin family genes and expression analysis during development in oriental river prawn, Macrobrachium nipponense.  

PubMed

This paper reports that Slow-tonic S2 tropomyosin (Sst) and Slow tropomyosin isoform (Sti) was highly expressed in androgenic gland transcriptome of Macrobrachium nipponense, which may play crucial roles in sexual differentiation to maleness. In this study, two Sst and Sti gene homologues designated as Mnsst and Mnsti were cloned and characterized from a freshwater prawn M. nipponense. The full-length cDNA of Mnsst and Mnsti consists of 997 bp and 1926 bp, respectively, with an ORF of 852 bp encoding 284 amino acids, and the similarity in ORF reached to 95.82%. The deduced amino acid sequences of Mnsst and Mnsti shared the highest identity with Slow-tonic S2 tropomyosin and Slow tropomyosin isoform of Homarus americanus. Real-time quantitative RT-PCR showed that the Mnsst and Mnsti genes were expressed in different tissues with the highest level of expression in the androgenic gland, implying that these two genes may be related to sex-determination in M. nipponense. Real-time quantitative RT-PCR revealed that in addition, Mnsst and Mnsti were speculated to be related with embryonic organogenesis of M. nipponense, especially for the formation of complete mouthpart and digestive organ and stimulating larval changes of morphology and initiate metamorphosis, the results of present study implied that the two genes may play complex and important roles in sex differentiation of M. nipponense. Thus, we isolated two candidate genes that may advance the studies of sex-determination mechanism in M. nipponense and even the whole crustacean species, as well as promoting the all-male population culture of M. nipponense. PMID:24809964

Jin, Shubo; Jiang, Sufei; Xiong, Yiwei; Qiao, Hui; Sun, Shengming; Zhang, Wenyi; Li, Fajun; Gong, Yongsheng; Fu, Hongtuo

2014-08-10

103

A kinetic characterization of the gill V(H(+))-ATPase in juvenile and adult Macrobrachium amazonicum, a diadromous palaemonid shrimp.  

PubMed

Novel kinetic properties of a microsomal gill V(H(+))-ATPase from juvenile and adult Amazon River shrimp, Macrobrachium amazonicum, are described. While protein expression patterns are markedly different, Western blot analysis reveals a sole immunoreactive band, suggesting a single V(H(+))-ATPase subunit isoform, distributed in membrane fractions of similar density in both ontogenetic stages. Immunofluorescence labeling locates the V(H(+))-ATPase in the apical regions of the lamellar pillar cells in both stages in which mRNA expression of the V(H(+))-ATPase B-subunit is identical. Juvenile (36.6±3.3nmolPimin(-)(1) mg(-)(1)) and adult (41.6±1.3nmolPi min(-)(1) mg(-)(1)) V(H(+))-ATPase activities are similar, the apparent affinity for ATP of the adult enzyme (K0.5=0.21±0.02mmolL(-)(1)) being 3-fold greater than for juveniles (K0.5=0.61±0.01mmolL(-)(1)). The K0.5 for Mg(2+) interaction with the juvenile V(H(+))-ATPase (1.40 ± 0.07 mmol L(-)(1)) is ?6-fold greater than for adults (0.26±0.02mmolL(-)(1)) while the bafilomycin A1 inhibition constant (KI) is 45.0±2.3nmolL(-)(1) and 24.2±1.2nmolL(-)(1), for juveniles and adults, respectively. Both stages exhibited residual bafilomycin-insensitive ATPase activity of ?25 nmol Pi min(-)(1) mg(-)(1), suggesting the presence of ATPases other than the V(H(+))-ATPase. These differences may reflect a long-term regulatory mechanism of V(H(+))-ATPase activity, and suggest stage-specific enzyme modulation. This is the first kinetic analysis of V(H(+))-ATPase activity in different ontogenetic stages of a freshwater shrimp and allows better comprehension of the biochemical adaptations underpinning the establishment of palaemonid shrimps in fresh water. PMID:25461614

Lucena, Malson N; Pinto, Marcelo R; Garçon, Daniela P; McNamara, John C; Leone, Francisco A

2014-11-15

104

Comparative acute toxicity of gallium(III), antimony(III), indium(III), cadmium(II), and copper(II) on freshwater swamp shrimp (Macrobrachium nipponense)  

PubMed Central

Background Acute toxicity testing were carried out the freshwater swamp shrimp, Macrobrachium nipponense, as the model animal for the semiconductor applied metals (gallium, antimony, indium, cadmium, and copper) to evaluate if the species is an suitable experimental animal of pollution in aquatic ecosystem. Results The static renewal test method of acute lethal concentrations determination was used, and water temperature was maintained at 24.0?±?0.5°C. Data of individual metal obtained from acute toxicity tests were determined using probit analysis method. The median lethal concentration (96-h LC50) of gallium, antimony, indium, cadmium, and copper for M. nipponense were estimated as 2.7742, 1.9626, 6.8938, 0.0539, and 0.0313 mg/L, respectively. Conclusions Comparing the toxicity tolerance of M. nipponense with other species which exposed to these metals, it is obviously that the M. nipponense is more sensitive than that of various other aquatic animals. PMID:25027256

2014-01-01

105

The Prawn Macrobrachium vollenhovenii in the Senegal River Basin: Towards Sustainable Restocking of All-Male Populations for Biological Control of Schistosomiasis  

PubMed Central

Early malacological literature suggests that the outbreak of schistosomiasis, a parasitic disease transmitted by aquatic snails, in the Senegal River basin occurred due to ecological changes resulting from the construction of the Diama dam. The common treatment, the drug praziquantel, does not protect from the high risk of re-infection due to human contact with infested water on a daily basis. The construction of the dam interfered with the life cycle of the prawn Macrobrachium vollenhovenii by blocking its access to breeding grounds in the estuary. These prawns were demonstrated to be potential biological control agents, being effective predators of Schistosoma-susceptible snails. Here, we propose a responsible restocking strategy using all-male prawn populations which could provide sustainable disease control. Male prawns reach a larger size and have a lower tendency to migrate than females. We, therefore, expect that periodic restocking of all-male juveniles will decrease the prevalence of schistosomiasis and increase villagers' welfare. In this interdisciplinary study, we examined current prawn abundance along the river basin, complemented with a retrospective questionnaire completed by local fishermen. We revealed the current absence of prawns upriver and thus demonstrated the need for restocking. Since male prawns are suggested to be preferable for bio-control, we laid the molecular foundation for production of all-male M. vollenhovenii through a complete sequencing of the insulin-like androgenic gland-encoding gene (IAG), which is responsible for sexual differentiation in crustaceans. We also conducted bioinformatics and immunohistochemistry analyses to demonstrate the similarity of this sequence to the IAG of another Macrobrachium species in which neo-females are produced and their progeny are 100% males. At least 100 million people at risk of schistosomiasis are residents of areas that experienced water management manipulations. Our suggested non-breeding sustainable model of control—if proven successful—could prevent re-infections and thus prove useful throughout the world. PMID:25166746

Savaya Alkalay, Amit; Rosen, Ohad; Sokolow, Susanne H.; Faye, Yacinthe P. W.; Faye, Djibril S.; Aflalo, Eliahu D.; Jouanard, Nicolas; Zilberg, Dina; Huttinger, Elizabeth; Sagi, Amir

2014-01-01

106

Transcriptome Analysis of Androgenic Gland for Discovery of Novel Genes from the Oriental River Prawn, Macrobrachium nipponense, Using Illumina Hiseq 2000  

PubMed Central

Background The oriental river prawn, Macrobrachium nipponense, is an important aquaculture species in China, even in whole of Asia. The androgenic gland produces hormones that play crucial roles in sexual differentiation to maleness. This study is the first de novo M. nipponense transcriptome analysis using cDNA prepared from mRNA isolated from the androgenic gland. Illumina/Solexa was used for sequencing. Methodology and Principal Finding The total volume of RNA sample was more than 5 ug. We generated 70,853,361 high quality reads after eliminating adapter sequences and filtering out low-quality reads. A total of 78,408 isosequences were obtained by clustering and assembly of the clean reads, producing 57,619 non-redundant transcripts with an average length of 1244.19 bp. In total 70,702 isosequences were matched to the Nr database, additional analyses were performed by GO (33,203), KEGG (17,868), and COG analyses (13,817), identifying the potential genes and their functions. A total of 47 sex-determination related gene families were identified from the M. nipponense androgenic gland transcriptome based on the functional annotation of non-redundant transcripts and comparisons with the published literature. Furthermore, a total of 40 candidate novel genes were found, that may contribute to sex-determination based on their extremely high expression levels in the androgenic compared to other sex glands,. Further, 437 SSRs and 65,535 high-confidence SNPs were identified in this EST dataset from which 14 EST-SSR markers have been isolated. Conclusion Our study provides new sequence information for M. nipponense, which will be the basis for further genetic studies on decapods crustaceans. More importantly, this study dramatically improves understanding of sex-determination mechanisms, and advances sex-determination research in all crustacean species. The huge number of potential SSR and SNP markers isolated from the transcriptome may shed the lights on research in many fields, including the evolution and molecular ecology of Macrobrachium species. PMID:24204682

Jin, Shubo; Fu, Hongtuo; Zhou, Qiao; Sun, Shengming; Jiang, Sufei; Xiong, Yiwei; Gong, Yongsheng; Qiao, Hui; Zhang, Wenyi

2013-01-01

107

Marine Fisheries On the cover  

E-print Network

Marine Fisheries ~~WD~~ On the cover: A spring chinook gillnetter on the Columbia River at Astoria, Macrobrachium rosenbergii Departments NOAA/NMFS Developments Foreign Fishery Developments Index Papers in Marine For Fisheries National Marine Fisheries Service Editor: W. Hobart Marine Fisheries Review (USPS 090-080) is pub

108

A Simple "in Vitro" Culture of Freshwater Prawn Embryos for Laboratory Investigations  

ERIC Educational Resources Information Center

Giant freshwater prawn ("Macrobrachium rosenbergii" De Man) embryos can be cultured "in vitro" to hatching in 15% (v/v) artificial seawater (ASW). This technique can be applied as a bioassay for testing toxicity or for the effects of various substances on embryo development and can be used as a simple and low-cost model for studying embryo…

Porntrai, Supaporn; Damrongphol, Praneet

2008-01-01

109

Levels of platinum group metals in selected species (Sarotherodon melanotheron, Chonophorus lateristriga, Macrobrachium vollenhovenii and Crassostrea tulipa) in some estuaries and lagoons along the coast of Ghana.  

PubMed

The use of some biota as bioindicators of heavy metal pollution has been demonstrated as particularly adequate due to their capacity of bioconcentration. This study evaluated the levels of platinum group metals (PGMs) in some selected species along the coastal belt of Ghana, using the neutron activation analysis (NAA) method. The result was processed to evaluate pollution indices in order to map the distribution of the metals in those species in the lagoons and estuaries along the costal belt of Ghana. The analysis showed significant levels of all PGMs in blackchin tilapia (Sarotherodon melanotheron Cichlidae), brown goby (Chonophorus lateristriga Gobiidae), shrimp (Macrobrachium vollenhovenii Palaemonidae), and mangrove oysters (Crassostrea tulipa Ostreidae) in the lagoons and river Pra estuary. However, the oysters showed an elevated mean concentration of 0.13 ?g/g (dry weight) Pd. From the pollution indices, most of the sampling sites registered mean contamination factor (CF) values between 1.20 and 3.00 for Pt, Pd, and Rh. The pollution load index (PLI) conducted also gave an average pollution index between 0.79 and 2.37, indicating progressive contamination levels. The results revealed that anthropogenic sources, industrial and hospital effluent, etc., together with vehicular emissions, could be the contributing factors to the deposition of PGMs along the Ghanaian coast. PMID:20953547

Essumang, D K; Adokoh, C K; Boamponsem, L

2010-01-01

110

Determination of microcystin-LR and its metabolites in snail (Bellamya aeruginosa), shrimp (Macrobrachium nipponensis) and silver carp (Hypophthalmichthys molitrix) from Lake Taihu, China.  

PubMed

This paper describes seasonal changes of microcystin-LR (MC-LR) and its glutathione (MC-LR-GSH) and cysteine conjugates (MC-LR-Cys) in three aquatic animals--snail (Bellamya aeruginosa), shrimp (Macrobrachium nipponensis) and silver carp (Hypophthalmichthys molitrix) collected from Lake Taihu, China. MC-LR, MC-LR-GSH, and MC-LR-Cys were determined by liquid chromatography electrospray ionization mass spectrum (LC-ESI-MS). The mean MC-LR concentrations in the hepatopancreas of snail and shrimp and liver of silver carp were 6.61, 0.24, and 0.027 microg g(-1) dry weight (DW), respectively; while the average MC-LR-Cys concentrations were 0.50, 0.97, and 5.72 microg g(-1) DW, respectively. MC-LR-GSH was usually not detectable in these samples. The above results suggest that: (1) in aquatic animals, especially fish, the main excretion form of MC-LR could be MC-LR-Cys, but not MC-LR-GSH, whereas MC-LR-Cys might play an important role in detoxication of MC-LR and (2) that efficiency of MC-LR-Cys formation differs among species. The main detoxication pathway of MC-LR in aquatic animals is suggested as follows: when MC-LR enters into liver/hepatopancreas, it firstly conjugates with polypeptide or protein (including GSH, PP-1 and 2A) containing Cys residues, perhaps also some free cysteine; subsequently, MC-LR-Cys is degraded from these polypeptide or protein; and finally is excreted from animals by the compound of MC-LR-Cys. PMID:19473685

Zhang, Dawen; Xie, Ping; Chen, Jun; Dai, Ming; Qiu, Tong; Liu, Yaqin; Liang, Gaodao

2009-08-01

111

A marine bacterium, Micrococcus MCCB 104, antagonistic to vibrios in prawn larval rearing systems.  

PubMed

A marine bacterium, Micrococcus MCCB 104, isolated from hatchery water, demonstrated extracellular antagonistic properties against Vibrio alginolyticus, V. parahaemolyticus, V. vulnificus, V. fluviallis, V. nereis, V. proteolyticus, V. mediterranei, V cholerae and Aeromonas sp., bacteria associated with Macrobrachium rosenbergii larval rearing systems. The isolate inhibited the growth of V. alginolyticus during co-culture. The antagonistic component of the extracellular product was heat-stable and insensitive to proteases, lipase, catalase and alpha-amylase. Micrococcus MCCB 104 was demonstrated to be non-pathogenic to M. rosenbergii larvae. PMID:16465832

Jayaprakash, N S; Pai, S Somnath; Anas, A; Preetha, R; Philip, Rosamma; Singh, I S Bright

2005-12-30

112

Multi-culture solar heated bio-shelter. Final report  

SciTech Connect

A rooftop greenhouse (bio-shelter) that is heated with active and passive solar systems is presented. The intent of the greenhouse is to grow vegetables hydroponically the year-round using a nutrient flow technique; and to growth the giant tropical Malaysian prawn Macrobrachium rosenbergii in a recycling raceway water system heated with solar power. The produce grown was continuously monitored and the harvests weighed in order to estimate the year-round production potential of the bio-shelter greenhouse.

Not Available

1985-01-01

113

Direct use of low temperature geothermal water by Aquafarms International, Inc. for freshwater aquaculture (prawns and associated species). An operations and maintenance manual  

SciTech Connect

In connection with an ongoing commercial aquaculture project in the Coachella Valley, California; a twelve month prawn growout demonstration project was conducted. This project began in August, 1979 and involved the use of low temperature (85/sup 0/F) geothermal waters to raise freshwater prawns, Macrobrachium rosenbergii (deMan), in earthen ponds. The following publication is an operations and maintenance guide which may by useful for those interested in conducting similar enterprises.

Broughton, R.; Price, M.; Price, V.; Grajcer, D.

1984-04-01

114

Organochlorine Pesticides and Biomarker Responses in Two Fishes Oreochromis niloticus (Linnaeus, 1758) and Chrysichthys nigrodigitatus (Lacepede, 1803) and an Invertebrate, Macrobrachium vollenhovenii (Herklot, 1857), from the Lake Taabo (Cote d`Ivoire)  

NASA Astrophysics Data System (ADS)

The concentrations of organochlorine pesticides (OCPs) were determined in muscle samples of two species of fish, tilapia (Oreochromis niloticus) and the catfish (Chrysichthys nigrodigitatus) and the prawn (Macrobrachium vollenhovenii) found in Lake Taabo (Cote d`Ivoire). Simultaneous measurements of enzymatic biomarkers were made to evaluate the ecotoxicological risk in this hydroelectric reservoir. Lindane and endosulfan were the dominant contaminants, suggesting their current use in neighboring agricultural areas. Other organochlorine (OC) compounds were detected, including some currently banned substances. Ranked in an order of descending concentrations, we found: DDT and its metabolites (17.8-57.2 ng g-1 dry weight), endrin (7.17-25.0 ng g-1 dry weight) and heptachlor (7.36-23.6 ng g-1 dry weight), as well as traces of isomers of chlordane, aldrin and fipronil. The hepatic Glutathione S-Transferase (GST) activity measured in fishes was not correlated with pesticide contamination; whereas the antioxidant biomarkers demonstrated some significant associations, especially hepatic catalase with lindane (R = 0.83) and Glutathione Peroxidase (GPx) with heptachlor epoxide (R = 0.84) and with pp`DDT (R = 0.81). In the prawns, acetylcholinesterase (AChE) activity showed significant negative correlations with DDT and its metabolites (R = -0.91). The results of this study emphasize the urgent need for overall environmental risk assessment studies in the region of Taabo and other developing areas.

Roche, Helene; Tidou, Abiba; Persic, Ana

115

Kinetic analysis of gill (Na?,K?)-ATPase activity in selected ontogenetic stages of the Amazon River shrimp, Macrobrachium amazonicum (Decapoda, Palaemonidae): interactions at ATP- and cation-binding sites.  

PubMed

We investigated modulation by ATP, Mg²?, Na?, K? and NH?? and inhibition by ouabain of (Na?,K?)-ATPase activity in microsomal homogenates of whole zoeae I and decapodid III (formerly zoea IX) and whole-body and gill homogenates of juvenile and adult Amazon River shrimps, Macrobrachium amazonicum. (Na?,K?)-ATPase-specific activity was increased twofold in decapodid III compared to zoea I, juveniles and adults, suggesting an important role in this ontogenetic stage. The apparent affinity for ATP (K(M) = 0.09 ± 0.01 mmol L?¹) of the decapodid III (Na?,K?)-ATPase, about twofold greater than the other stages, further highlights this relevance. Modulation of (Na?,K?-ATPase activity by K? also revealed a threefold greater affinity for K? (K?.? = 0.91 ± 0.04 mmol L?¹) in decapodid III than in other stages; NH?? had no modulatory effect. The affinity for Na? (K?.? = 13.2 ± 0.6 mmol L?¹) of zoea I (Na?,K?)-ATPase was fourfold less than other stages. Modulation by Na?, Mg²? and NH?? obeyed cooperative kinetics, while K? modulation exhibited Michaelis-Menten behavior. Rates of maximal Mg²? stimulation of ouabain-insensitive ATPase activity differed in each ontogenetic stage, suggesting that Mg²?-stimulated ATPases other than (Na?,K?)-ATPase are present. Ouabain inhibition suggests that, among the various ATPase activities present in the different stages, Na?-ATPase may be involved in the ontogeny of osmoregulation in larval M. amazonicum. The NH??-stimulated, ouabain-insensitive ATPase activity seen in zoea I and decapodid III may reflect a stage-specific means of ammonia excretion since functional gills are absent in the early larval stages. PMID:22544049

Leone, Francisco Assis; Masui, Douglas Chodi; de Souza Bezerra, Thais Milena; Garçon, Daniela Pereira; Valenti, Wagner Cotroni; Augusto, Alessandra Silva; McNamara, John Campbell

2012-04-01

116

Natural and Experimental Infection of Caenorhabditis Nematodes by Novel Viruses Related to Nodaviruses  

E-print Network

, Tony Be´licard1 , Yanfang Jiang3 , Guoyan Zhao3 , Carl J. Franz3 , Leonard D. Goldstein2 , Mabel. Louis, Missouri, United States of America Abstract An ideal model system to study antiviral immunity

Wang, David

117

Identification of a novel cognate cytosolic Hsp70 gene (MnHsc70-2) from oriental river prawn Macrobrachium nipponense and comparison of its expressions with the first cognate Hsc70 (MnHsc70-1) under different stresses.  

PubMed

The 70-kDa family of heat-shock proteins (Hsp70) plays an important role in the host immunity, which is widely expressed in eukaryotic cells as a major chaperone protein. In the present study, the full-length complementary DNA (cDNA) of a second cognate cytosolic Hsp70 family member (MnHsc70-2) was cloned and characterized from Macrobrachium nipponense, which is an economically and nutritionally important crustacean. The cDNA was 2,717 bp, containing an open reading frame (ORF) of 1,950 bp, which encodes a protein of 649 amino acids with a theoretical molecular weight of 71.1 kDa and an isoelectric point of 5.27. Sequence alignment showed that the MnHsc70-2 shared 75-97 % identity with other heat-shock proteins. Compared to the previously identified cognate Hsp70 (MnHsc70-1) in M. nipponense, MnHsc70-2 showed quite different expression profiles under unstressed conditions in all tested tissues, including the hemocytes, heart, hepatopancreas, gill, intestine, nerve, and muscle. The phylogenetic analysis demonstrated that MnHsc70-2 showed the closest relationship with MnHsc70-1. Heat-inducibility assays showed that two isolated messenger RNAs (mRNAs) displayed different expression profiles in both the hepatopancreas and gill tissues. MnHsc70-1 mRNA expression level decreased at first and then increased to the normal level, whereas MnHsc70-2 mRNA level increased at first and then decreased. The expressions of two MnHsc70s showed substantial obvious heat-inducible regulation in both the hepatopancreas and gill. Under bacterial challenge by Aeromonas hydrophila, both MnHsc70-1 and MnHsc70-2 mRNA level was up-regulated moderately. The results suggested that two cognate Hsc70s may play essential functions in mediating responses to heat-shock and bacterial challenge. PMID:24859888

Xiu, Yunji; Feng, Jia; Lu, Weiqiang; Liu, Dandan; Wu, Ting; Zhu, Huanxi; Liu, Peng; Li, Wenjie; Ren, Qian; Gu, Wei; Meng, Qingguo; Wang, Wen

2014-11-01

118

The invasion of five alien species in the Delta do Parnaíba Environmental Protection Area, Northeastern Brazil.  

PubMed

Marine biological invasions have been regarded as one of the major causes of native biodiversity loss, with shipping and aquaculture being the leading contributors for the introductions of alien species in aquatic ecosystems. In the present study, five aquatic alien species (one mollusk, three crustaceans and one fish species) were detected during dives, shore searches and from the fisheries on the coast of the Delta do Parnaíba Environmental Protection Area, in the States of Piauí and Maranhão, Northeastern Brazil. The species were the bicolor purse-oyster Isognomon bicolor, the whiteleg shrimp Litopenaeus vannamei, the giant river prawn Macrobrachium rosenbergii, the Indo-Pacific swimming crab Charybdis hellerii and, the muzzled blenny Omobranchus punctatus. Ballast water (I. bicolor, C. hellerii, and O. punctatus) and aquaculture activities (L. vannamei and M. rosenbergii) in adjacent areas are the most likely vectors of introduction. All exotic species found have potential impact risks to the environment because they are able to compete against native species for resources (food and habitat). Isognomon bicolor share the same habitat and food items with the native bivalve species of mussels and barnacles. Litopenaeus vannamei share the same habitat and food items with the native penaeids such as the pinkspot shrimp Farfantepenaeus brasiliensis, the Southern brown shrimp Farfantepenaeus subtilis, and the Southern white shrimp Litopenaeus schmitti, and in the past few years L. vannamei was responsible for a viral epidemics in the cultivation tanks that could be transmitted to native penaeid shrimps. Charybdis hellerii is also able to cause impacts on the local fisheries as the species can decrease the populations of native portunid crabs which are commercialized in the studied region. Macrobrachium rosenbergii may be sharing natural resources with the Amazon River prawn Macrobrachium amazonicum. Omobranchus punctatus shares habit with the native redlip blenny Ophioblennius atlanticus and other fishes, such as the frillfin goby Bathigobius soporator Some immediate remedial measures to prevent further introductions from ballast water and shrimp farm ponds should be: (i) to prevent the release of ballast water by ship/vessels in the region; (ii) to reroute all effluent waters from shrimp rearing facilities through an underground or above-ground dry well; (iii) to install adequate sand and gravel filter which will allow passage of water but not livestock; (iv) outdoor shrimp pounds located on floodable land should be diked, and; (v) to promote environmental awareness of those directly involved with ballast water (crews of ship/vessels) and shrimp farms in the region. PMID:20737846

Loebmann, Daniel; Mai, Ana Cecília G; Lee, James T

2010-09-01

119

Total and inorganic arsenic in freshwater fish and prawn in Thailand.  

PubMed

Total and inorganic arsenic levels were determined in 120 samples of eight freshwater animal species collected from five distribution centers in the central region of Thailand between January and March 2011. Eight species with the highest annual catch, consisting of seven fish species and one prawn species, were analyzed. Concentrations of inorganic arsenic (on a wet weight basis) ranged from 0.010 ?g/g in giant prawn (Macrobrachium rosenbergii) to 0.230 ?g/g in striped snakehead (Channa striata). Climbing perch (Anabas testudineus) exhibited the highest mean concentrations of total arsenic (0.459 ± 0.137 ?g/g), inorganic arsenic (0.121 ± 0.044 ?g/g), and percentage of inorganic arsenic (26.2%). Inorganic arsenic levels found in freshwater animals in this study were much lower than the Thai regulatory standard of 2 ?g/g. PMID:23043844

Saipan, Piyawat; Ruangwises, Suthep; Tengjaroenkul, Bundit; Ruangwises, Nongluck

2012-10-01

120

The aesthetasc concept: structural variations of putative olfactory receptor cell complexes in Crustacea.  

PubMed

The structure of the aesthetascs has been investigated in the prawn Macrobrachium rosenbergii (larvae and juveniles), the opossum shrimp Neomysis integer, the euphausid Meganyctiphanes, and in the water-fleas Daphnia magna and D. longispina. The aesthetascs, that are thought to represent olfactory receptors, exhibit a considerable structural variation, ranging from the well known aesthetascs of higher crustaceans (lobster, crab, crayfish) to the corresponding sensilla found in the water-fleas and the males of opossum shrimps. The two following morphological characteristics of the aesthetascs are thought to indicate an olfactory function: the shape of the cuticular hair that is long and essentially hose-shaped, and the thin, loosely arranged cuticle of at least the outer part of the cuticular hair. The presence of other structural elements such as sensory cells, cilia, and enveloping cells are vital for the olfactory function, but the development is variable, which makes their use in the morphological definition of aesthetascs problematic. PMID:1392063

Hallberg, E; Johansson, K U; Elofsson, R

1992-09-01

121

The Apparent Quorum-Sensing Inhibitory Activity of Pyrogallol Is a Side Effect of Peroxide Production  

PubMed Central

There currently is more and more interest in the use of natural products, such as tea polyphenols, as therapeutic agents. The polyphenol compound pyrogallol has been reported before to inhibit quorum-sensing-regulated bioluminescence in Vibrio harveyi. Here, we report that the addition of 10 mg · liter?1 pyrogallol protects both brine shrimp (Artemia franciscana) and giant river prawn (Macrobrachium rosenbergii) larvae from pathogenic Vibrio harveyi, whereas the compound showed relatively low toxicity (therapeutic index of 10). We further demonstrate that the apparent quorum-sensing-disrupting activity is a side effect of the peroxide-producing activity of this compound rather than true quorum-sensing inhibition. Our results emphasize that verification of minor toxic effects by using sensitive methods and the use of appropriate controls are essential when characterizing compounds as being able to disrupt quorum sensing. PMID:23545532

Pande, Gde Sasmita Julyantoro; Baruah, Kartik; Bossier, Peter

2013-01-01

122

The Vibrio campbellii quorum sensing signals have a different impact on virulence of the bacterium towards different crustacean hosts.  

PubMed

Pathogenic bacteria communicate with small signal molecules in a process called quorum sensing, and they often use different signal molecules to regulate virulence gene expression. Vibrio campbellii, one of the major pathogens of aquatic organisms, regulates virulence gene expression by a three channel quorum sensing system. Here we show that although they use a common signal transduction cascade, the signal molecules have a different impact on the virulence of the bacterium towards different hosts, i.e. the brine shrimp Artemia franciscana and the commercially important giant freshwater prawn Macrobrachium rosenbergii. These results suggest that the use of multiple types of signal molecules to regulate virulence gene expression is one of the features that allow bacteria to infect different hosts. Our findings emphasize that it is highly important to study the efficacy of quorum sensing inhibitors as novel biocontrol agents under conditions that are as close as possible to the clinical situation. PMID:24055027

Pande, Gde Sasmita Julyantoro; Natrah, Fatin Mohd Ikhsan; Sorgeloos, Patrick; Bossier, Peter; Defoirdt, Tom

2013-12-27

123

The apparent quorum-sensing inhibitory activity of pyrogallol is a side effect of peroxide production.  

PubMed

There currently is more and more interest in the use of natural products, such as tea polyphenols, as therapeutic agents. The polyphenol compound pyrogallol has been reported before to inhibit quorum-sensing-regulated bioluminescence in Vibrio harveyi. Here, we report that the addition of 10 mg · liter(-1) pyrogallol protects both brine shrimp (Artemia franciscana) and giant river prawn (Macrobrachium rosenbergii) larvae from pathogenic Vibrio harveyi, whereas the compound showed relatively low toxicity (therapeutic index of 10). We further demonstrate that the apparent quorum-sensing-disrupting activity is a side effect of the peroxide-producing activity of this compound rather than true quorum-sensing inhibition. Our results emphasize that verification of minor toxic effects by using sensitive methods and the use of appropriate controls are essential when characterizing compounds as being able to disrupt quorum sensing. PMID:23545532

Defoirdt, Tom; Pande, Gde Sasmita Julyantoro; Baruah, Kartik; Bossier, Peter

2013-06-01

124

Characterization of Virus-like Particles Assembled in a Recombinant Baculovirus System Expressing the Capsid Protein of a Fish Nodavirus  

Microsoft Academic Search

Betanodaviruses are causative agents of neurological disorders in several species of fish. We cloned and sequenced the RNA2 segment of two grouper viruses isolated from Epinephelus malabaricus (malabaricus grouper nervous necrosis virus, MGNNV) and Epinephelus lanceolatus (dragon grouper nervous necrosis virus, DGNNV). The sequences of the two RNAs were 99% identical and comparison with previously sequenced RNA2 segments of fish

Chan-Shing Lin; Ming-Wei Lu; Liang Tang; Wangta Liu; Chia-Ben Chao; Chun Ju Lin; Neel K. Krishna; John E. Johnson; Anette Schneemann

2001-01-01

125

Involvement of fish signal transducer and activator of transcription 3 (STAT3) in nodavirus infection induced cell death.  

PubMed

The Janus kinase (JAK)-signal transducer and activator of transcription (STAT) signaling pathway is an important signaling pathway activated by interferons in response to virus infection. Fish STAT3 has been demonstrated to be involved in Singapore grouper iridovirus (SGIV) infection and virus induced paraptosis, but its effects on the replication of other fish viruses still remained uncertain. Here, the roles of grouper STAT3 (Ec-STAT3) in red spotted grouper nervous necrosis virus (RGNNV) infection were investigated. The present data showed that the distribution of phosphorylated Ec-STAT3 was altered in RGNNV infected fish cells, and the promoter activity of STAT3 was significantly increased during virus infection, suggesting that STAT3 activation was involved in RGNNV infection. Using STAT3 specific inhibitor, we found that inhibition of Ec-STAT3 in vitro did not affect the transcription and protein synthesis of RGNNV coat protein (CP), however, the severity of RGNNV induced vacuolation and autophagy was significantly increased. Meanwhile, at the late stage of virus infection, RGNNV induced necrotic cell death was significantly decreased after inhibition of Ec-STAT3. Further studies indicated that Ec-STAT3 inhibition significantly increased the transcript level of autophagy related genes, including UNC-51-like kinase 2 (ULK2) and microtubule-associated protein 1 light chain 3-II (LC3-II) induced by RGNNV infection. Moreover, the expression of several pro-inflammatory factors, including TNF?, IL-1? and IL-8 were mediated by Ec-STAT3 during RGNNV infection. Together, our results not only firstly revealed that STAT3 exerted novel roles in response to fish virus infection, but also provided new insights into understanding the roles of STAT3 in different forms of programmed cell death. PMID:25555814

Huang, Youhua; Huang, Xiaohong; Yang, Ying; Wang, Wei; Yu, Yepin; Qin, Qiwei

2015-03-01

126

In-Depth Tanscriptomic Analysis on Giant Freshwater Prawns  

PubMed Central

Gene discovery in the Malaysian giant freshwater prawn (Macrobrachium rosenbergii) has been limited to small scale data collection, despite great interest in various research fields related to the commercial significance of this species. Next generation sequencing technologies that have been developed recently and enabled whole transcriptome sequencing (RNA-seq), have allowed generation of large scale functional genomics data sets in a shorter time than was previously possible. Using this technology, transcriptome sequencing of three tissue types: hepatopancreas, gill and muscle, has been undertaken to generate functional genomics data for M. rosenbergii at a massive scale. De novo assembly of 75-bp paired end Ilumina reads has generated 102,230 unigenes. Sequence homology search and in silico prediction have identified known and novel protein coding candidate genes (?24%), non-coding RNA, and repetitive elements in the transcriptome. Potential markers consisting of simple sequence repeats associated with known protein coding genes have been successfully identified. Using KEGG pathway enrichment, differentially expressed genes in different tissues were systematically represented. The functions of gill and hepatopancreas in the context of neuroactive regulation, metabolism, reproduction, environmental stress and disease responses are described and support relevant experimental studies conducted previously in M. rosenbergii and other crustaceans. This large scale gene discovery represents the most extensive transcriptome data for freshwater prawn. Comparison with model organisms has paved the path to address the possible conserved biological entities shared between vertebrates and crustaceans. The functional genomics resources generated from this study provide the basis for constructing hypotheses for future molecular research in the freshwater shrimp. PMID:23734171

Mohd-Shamsudin, Maizatul Izzah; Kang, Yi; Lili, Zhao; Tan, Tian Tian; Kwong, Qi Bin; Liu, Hang; Zhang, Guojie; Othman, Rofina Yasmin; Bhassu, Subha

2013-01-01

127

A novel single-domain peptide, anti-LPS factor from prawn: synthesis of peptide, antimicrobial properties and complete molecular characterization.  

PubMed

In this study, we reported a complete molecular characterization including bioinformatics features, gene expression, peptide synthesis and its antimicrobial activities of an anti-lipopolysaccharide (LPS) factor (ALF) cDNA identified from the established cDNA library of freshwater prawn Macrobrachium rosenbergii (named as MrALF). The mature protein has an estimated molecular weight of 11.240 kDa with an isoelectric point of 9.46. The bioinformatics analysis showed that the MrALF contains an antimicrobial peptide (AMP) region between T54 and P77 with two conserved cysteine residues (Cys55 and Cys76) which have an anti-parallel ?-sheet confirmation. The ?-sheet is predicted as cationic with hydrophobic nature containing a net charge of +5. The depicted AMP region is determined to be amphipathic with a predicted hydrophobic face 'FPVFI'. A highest MrALF gene expression was observed in hemocytes and is up-regulated with virus [white spot syndrome baculovirus (WSBV)], bacteria (Aeromonas hydrophila) and Escherichia coli LPS at various time points. The LPS binding region of MrALF peptide was synthesized to study the antimicrobial property, bactericidal efficiency and hemolytic capacity. The peptide showed antimicrobial activity against both the Gram-negative and Gram-positive bacteria. The bactericidal assay showed that the peptide recognized the LPS of bacterial cell walls and binding on its substrate and thereby efficiently distinguishing the pathogens. The hemolytic activity of MrALF peptide is functioning in a concentration dependant manner. In summary, the comprehensive analysis of MrALF showed it to be an effective antimicrobial peptide and thus it plays a crucial role in the defense mechanism of M. rosenbergii. PMID:24269604

Arockiaraj, Jesu; Kumaresan, Venkatesh; Bhatt, Prasanth; Palanisamy, Rajesh; Gnanam, Annie J; Pasupuleti, Mukesh; Kasi, Marimuthu; Chaurasia, Mukesh Kumar

2014-03-01

128

Stability of the WSSV ORF94 VNTR genotype marker during passage in marine shrimp, freshwater crayfish and freshwater prawns.  

PubMed

The white spot syndrome virus (WSSV) genome contains 3 variable number tandem repeat (VNTR) regions, located in open reading frame (ORF) 75, ORF94 and ORF125, which have been employed for molecular epizootiological studies. A previous report suggested that the ORF 94 VNTR is highly unstable, varying in the number of tandem repeats during single passages from shrimp to other crustaceans. As such rapid variations would have profound implications for the interpretation of molecular epizootiological data, we re-examined the stability of the ORF94 VNTR. Two WSSV isolates with different ORF94 VNTR genotypes (TRS5 and TRS7) were obtained from disease outbreaks in farmed black tiger shrimp Penaeus monodon in Indonesia. High titre stocks of each virus were produced by injection in specific pathogen-free (SPF) Pacific white shrimp Litopenaeus vannamei with filtered infected tissue extracts, and the genotypes were confirmed. Each stock (macerated tissue) was then used to feed SPF Pacific white shrimp, freshwater crayfish (Cherax sp.) and freshwater prawns Macrobrachium rosenbergii through 3 successive passages involving alternative hosts at each level. Taqman real-time PCR was conducted on samples from each group to confirm infection and quantify viral genetic loads. ORF94 VNTR genotype analysis conducted on samples from each of the 43 passage groups indicated no variations in the VNTR number in either genotype TRS5 or genotype TRS7. This finding is contrary to the previous report and suggests that ORF94 VNTR are stable during multiple passages in these crustaceans. PMID:25320037

Gudkovs, Nicholas; Murwantoko, Murwantoko; Walker, Peter J

2014-10-16

129

Effect of stocking density on extensive production of freshwater shrimp in coal mine reclamation ponds  

SciTech Connect

The use of post-mining reclamation ponds for the production of freshwater shrimp was evaluated by examining different stocking densities. Juvenile shrimp (Macrobrachium rosenbergii) averaging 0.5g each were stocked into four existing ponds at Peabody`s Ken Surface Mine at 6,175; 12,350; 18,500; and 24,700/ha (2,500, 5,000, 7,500, and 10,000/acre) on June 1, 1995. Shrimp were fed twice a week for 103 days, with harvest conducted September 13, 1995. Survival averaged 40%, overall. Average individual weight size was inversely related to stocking density ranging from 52 g (8.7 shrimp/lb) at 6,175/ha to 20.3 g (22.7 shrimp/lb) at 18,500/acre. Total production was directly related to stocking density ranging from 97 kg/ha (86 lbs/acre) at low density to 211 kg/ha (188 lbs/acre) at 18,500/ha shrimp acre. The major difficulty was at harvest due to difficulty in draining ponds. Construction of designed culture ponds with gravity drains during reclamation could greatly enhance survival, harvestability, and commercial feasibility.

Tidwell, J.H.; Wynne, F.; Coyle, S.D. [Kentucky State Univ., Frankfort, KY (United States). Aquaculture Research Center; Grey, B. [Peabody Coal Co., Rockport, KY (United States); McGuire, J.

1998-12-31

130

Fishing for prawn larvae in Bangladesh: an important coastal livelihood causing negative effects on the environment.  

PubMed

Freshwater prawn (Macrobrachium rosenbergii) farming in Bangladesh has, to a large extent, been dependent on the supply of wild larvae. Although there are 81 freshwater prawn hatcheries in the country, a lack of technical knowledge, inadequate skilled manpower, and an insufficient supply of wild broods have limited hatchery production. Many thousands of coastal poor people, including women, are engaged in fishing for wild prawn larvae along the coastline during a few months each year. On average, 40% of the total yearly income for these people comes from prawn larvae fishing activity. However, indiscriminate fishing of wild larvae, with high levels of bycatch of juvenile fish and crustaceans, may impact negatively on production and biodiversity in coastal ecosystems. This concern has provoked the imposition of restrictions on larvae collection. The ban has, however, not been firmly enforced because of the limited availability of hatchery-raised larvae, the lack of an alternative livelihood for people involved in larvae fishing, and weak enforcement power. This article discusses the environmental and social consequences of prawn larvae fishing and concludes that, by increasing awareness among fry fishers, improving fishing techniques (reducing bycatch mortality), and improving the survival of fry in the market chain, a temporal ban may be a prudent measure when considering the potential negative impacts of bycatch. However, it also suggests that more research is needed to find out about the impact of larvae fishing on nontarget organisms and on the populations of targeted species. PMID:20496649

Ahmed, Nesar; Troell, Max

2010-02-01

131

Expression of an Androgenic Gland-Specific Insulin-Like Peptide during the Course of Prawn Sexual and Morphotypic Differentiation  

PubMed Central

The crustacean male-specific androgenic gland (AG) regulates sexual differentiation. In the prawn Macrobrachium rosenbergii, silencing an AG-specific insulin-like encoding transcript (Mr-IAG) inhibited the development of male sexual characters, suggesting that Mr-IAG is a key androgenic hormone. We used recombinant pro-Mr-IAG peptide to generate antibodies that recognized the peptide in AG cells and extracts, as verified by mass spectrometry. We revealed the temporal expression pattern of Mr-IAG and studied its relevance to the timetable of sex differentiation processes in juveniles and after puberty. Mr-IAG was expressed from as early as 20 days after metamorphosis, prior to the appearance of external male sexual characters. Mr-IAG expression was lower in the less reproductively active orange-clawed males than in both the dominant blue-clawed males and the actively sneak mating small males. These results suggest a role for Mr-IAG both in the timing of male sexual differentiation and in regulating reproductive strategies. PMID:22363879

Ventura, Tomer; Manor, Rivka; Aflalo, Eliahu D.; Weil, Simy; Khalaila, Isam; Rosen, Ohad; Sagi, Amir

2011-01-01

132

Identification of the essential and free amino acids of the freshwater shrimp, Macrobrachium ohione  

E-print Network

supplement, folic acid, biotin, niacin, thiamine, riboflavin supplement, pyridoxine hydrochloride, menadione sodium bisulfite (source of vitamin K activity), iron oxide, manganous oxide, copper oxide, cobalt carbonate, and zinc oxide. Ralston Purina...). Fractions of the column effluent were collected at 1 min intervals with n fraction collector. Aliqunts of each fraction were ninhydrin analyzed using a Technicon analytical system to determine the location of each amino acid peak. Fractions cor...

Miyajima, Lester Shigemi

1975-01-01

133

Ingestion and absorption of nutrients by the freshwater prawn (Macrobrachium rosengergii)  

E-print Network

: Dr. Robert R. Stickney The effects of feeding rate and feeding frequency on protein and total organic matter absorption as well as dry matter ingestion h I h*t 9 Il *b h' ~9*dt, * 1 t'9 d. Feeding rate and feeding frequency did not appear to have... significant effects on protein absorption. In most instances, no significant effects of feeding rate and feeding frequency on total organic matter absorption were observed. Feeding frequency of 2 times/day resulted in a significant increase in food...

Taechanuruk, Suchat

2012-06-07

134

Transcript profiles of mitochondrial and cytoplasmic manganese superoxide dismutases in Exopalaemon carinicauda under ammonia stress  

NASA Astrophysics Data System (ADS)

Superoxide dismutase (SOD) is one of the most important antioxidant defense enzymes, and is considered as the first line against oxidative stress. In this study, we cloned a mitochondrial manganese (Mn) SOD (mMnSOD) cDNA from the ridgetail white prawn Exopalaemon carinicauda by using rapid amplification of cDNA ends (RACE) methods. The full-length cDNA for mMnSOD was 1 014-bp long, containing a 5'-untranslated region (UTR) of 37-bp, a 3'-UTR of 321-bp with a poly (A) tail, and included a 657-bp open reading frame encoding a protein of 218 amino acids with a 16-amino-acid signal peptide. The protein had a calculated molecular weight of 23.87 kDa and a theoretical isoelectric point of 6.75. The mMnSOD sequence included two putative N-glycosylation sites (NHT and NLS), the MnSOD signature sequence 180DVWEHAYY187, and four putative Mn binding sites (H48, H96, D180, and H184). Sequence comparison showed that the mMnSOD deduced amino acid sequence of E. carinicauda shared 97%, 95%, 89%, 84%, 82%, 72%, and 69% identity with that of Macrobrachium rosenbergii, Macrobrachium nipponense, Fenneropeneaus chinensis, Callinectes sapidus, Perisesarma bidens, Danio rerio, and Homo sapiens, resectively. Quantitative real-time RT-PCR analysis showed that mMnSOD transcripts were present in all E. carinicauda tissues examined, with the highest levels in the hepatopancreas. During an ammonia stress treatment, the transcript levels of mMnSOD and cMnSOD were up-regulated at 12 h in hemocytes and at 24 h in the hepatopancreas. As the duration of the ammonia stress treatment extended to 72 h, the transcript levels of mMnSOD and cMnSOD significantly decreased both in hemocytes and hepatopancreas. These findings indicate that the SOD system is induced to respond to acute ammonia stress, and may be involved in environmental stress responses in E. carinicauda.

Ren, Hai; Li, Jian; Li, Jitao; Liu, Ping; Liang, Zhongxiu; Wu, Jianhua

2015-01-01

135

Molecular characterization of a cytosolic manganese superoxide dismutase from the Chinese mitten crab, Eriocheir sinensis.  

PubMed

A cytosolic manganese superoxide dismutase gene (Es-cMnSOD) was cloned from the Chinese mitten crab Eriocheir sinensis, using reverse transcription-polymerase chain reaction and the rapid amplification of cDNA ends. The open reading frame of Es-cMnSOD is 867 bp in length and encodes a 288-amino acid protein without a signal peptide. The calculated molecular mass of the translated protein of Es-cMnSOD is 31.43 kDa, with an estimated isoelectric point of 6.30. The deduced amino acid sequence of Es-cMnSOD has similarities of 90, 89, 84, 87, and 81% to those of white shrimp Litopenaeus vannamei MnSOD, black tiger shrimp Penaeus monodon MnSOD, giant freshwater prawn Macrobrachium rosenbergii MnSOD, blue crab Callinectes sapidus MnSOD, and red swamp crayfish Procambarus clarkii MnSOD, respectively. Es-cMnSOD contains a manganese superoxide dismutase domain (DVWEHAYY) and 4 conserved amino acids responsible for binding manganese. Es-cMnSOD was expressed in the hemocytes, eyestalk, muscle, intestine, gill, and hepatopancreas. Es-cMnSOD transcripts in hemocytes of E. sinensis increased at 1.5 and 48 h after injection of Aeromonas hydrophila, indicating that the induction of the SOD system response occurred within a short period of time. This study suggests that MnSOD may play a critical role in crab immunity, allowing efficient activation of an early innate immune response in the crab. PMID:25501153

Zhao, D X; Chen, L Q; Qin, J G; Qin, C J; Zhang, H; Wu, P; Li, E C

2014-01-01

136

FishMicrosat: a microsatellite database of commercially important fishes and shellfishes of the Indian subcontinent  

PubMed Central

Background Microsatellite DNA is one of many powerful genetic markers used for the construction of genetic linkage maps and the study of population genetics. The biological databases in public domain hold vast numbers of microsatellite sequences for many organisms including fishes. The microsatellite data available in these data sources were extracted and managed into a database that facilitates sequences analysis and browsing relevant information. The system also helps to design primer sequences for flanking regions of repeat loci for PCR identification of polymorphism within populations. Description FishMicrosat is a database of microsatellite sequences of fishes and shellfishes that includes important aquaculture species such as Lates calcarifer, Ctenopharyngodon idella, Hypophthalmichthys molitrix, Penaeus monodon, Labeo rohita, Oreochromis niloticus, Fenneropenaeus indicus and Macrobrachium rosenbergii. The database contains 4398 microsatellite sequences of 41 species belonging to 15 families from the Indian subcontinent. GenBank of NCBI was used as a prime data source for developing the database. The database presents information about simple and compound microsatellites, their clusters and locus orientation within sequences. The database has been integrated with different tools in a web interface such as primer designing, locus finding, mapping repeats, detecting similarities among sequences across species, and searching using motifs and keywords. In addition, the database has the ability to browse information on the top 10 families and the top 10 species, through record overview. Conclusions FishMicrosat database is a useful resource for fish and shellfish microsatellite analyses and locus identification across species, which has important applications in population genetics, evolutionary studies and genetic relatedness among species. The database can be expanded further to include the microsatellite data of fishes and shellfishes from other regions and available information on genome sequencing project of species of aquaculture importance. PMID:24047532

2013-01-01

137

Characterization of a Prawn OA/TA Receptor in Xenopus Oocytes Suggests Functional Selectivity between Octopamine and Tyramine  

PubMed Central

Here we report the characterization of an octopamine/tyramine (OA/TA or TyrR1) receptor (OA/TAMac) cloned from the freshwater prawn, Macrobrachium rosenbergii, an animal used in the study of agonistic social behavior. The invertebrate OA/TA receptors are seven trans-membrane domain G-protein coupled receptors that are related to vertebrate adrenergic receptors. Behavioral studies in arthropods indicate that octopaminergic signaling systems modulate fight or flight behaviors with octopamine and/or tyramine functioning in a similar way to the adrenalins in vertebrate systems. Despite the importance of octopamine signaling in behavioral studies of decapod crustaceans there are no functional data available for any of their octopamine or tyramine receptors. We expressed OA/TAMac in Xenopus oocytes where agonist-evoked trans-membrane currents were used as readouts of receptor activity. The currents were most effectively evoked by tyramine but were also evoked by octopamine and dopamine. They were effectively blocked by yohimbine. The electrophysiological approach we used enabled the continuous observation of complex dynamics over time. Using voltage steps, we were able to simultaneously resolve two types of endogenous currents that are affected over different time scales. At higher concentrations we observe that octopamine and tyramine can produce different and opposing effects on both of these currents, presumably through the activity of the single expressed receptor type. The pharmacological profile and apparent functional-selectivity are consistent with properties first observed in the OA/TA receptor from the insect Drosophila melanogaster. As the first functional data reported for any crustacean OA/TA receptor, these results suggest that functional-selectivity between tyramine and octopamine is a feature of this receptor type that may be conserved among arthropods. PMID:25350749

Jezzini, Sami H.; Reyes-Colón, Dalynés; Sosa, María A.

2014-01-01

138

Poly-ß-hydroxybutyrate content and dose of the bacterial carrier for Artemia enrichment determine the performance of giant freshwater prawn larvae.  

PubMed

The beneficial effects of poly-?-hydroxybutyrate (PHB) for aquaculture animals have been shown in several studies. The strategy of applying PHB contained in a bacterial carrier has, however, hardly been considered. The effect of administering PHB-accumulated Alcaligenes eutrophus H16 containing 10 or 80 % PHB on dry weight, named A10 and A80, respectively, through the live feed Artemia was investigated on the culture performance of larvae of the giant freshwater prawn (Macrobrachium rosenbergii). Feeding larvae with Artemia nauplii enriched in a medium containing 100 and 1,000 mg L(-1) A80 significantly increased the survival with about 15 % and the development of the larvae with a larval stage index of about 1 as compared to feeding non-enriched Artemia. The survival of the larvae also significantly increased with about 35 % in case of a challenge with Vibrio harveyi. The efficiency of these treatments was equal to a control treatment of Artemia enriched in an 800 mg L(-1) PHB powder suspension, while Artemia enriched in 10 mg L(-1) A80, 100 mg L(-1) A10, and 1,000 mg L(-1) A10 did not bring similar effects. From our results, it can be concluded that PHB supplemented in a bacterial carrier (i.e., amorphous PHB) can increase the larviculture efficiency of giant freshwater prawn similar to supplementation of PHB in powdered form (i.e., crystalline PHB). When the level of PHB in the bacterial carrier is high, similar beneficial effects can be achieved as crystalline PHB, but at a lower live food enrichment concentration expressed on PHB basis. PMID:24615382

Thai, Truong Quoc; Wille, Mathieu; Garcia-Gonzalez, Linsey; Sorgeloos, Patrick; Bossier, Peter; De Schryver, Peter

2014-06-01

139

Anomalous anatomy of identified neurons in the larval prawn: spontaneous and induced by microlesions.  

PubMed

The abdominal ganglia of the prawn Macrobrachium rosenbergii undergo developmental changes of fundamental interest between the time of hatching and metamorphosis. These changes include an increase in cell numbers and changes in the connectivity between identified neurons. The giant motoneurons involved in the escape response, which form a syncytium in the adult, are observed as separate neurons with crossed axons in early larvae. Anomalous growth and connections of identified neurons were studied in order to gain some understanding of the rules and mechanisms governing normal development. Spontaneous anomalies included: supernumerary axons and abnormal axonal trajectories. The plasticity and specificity of identified neurons were studied by following the anatomical effects of deletions of giant neurons. Microlesions were inflicted reproducibly by means of a focused beam of visible and ultraviolet light. Within a day, irradiated cell bodies are eliminated; complete disappearance of the axon takes about 10 days, indicating that the remarkable ability of some invertebrate neurons to survive without a soma is not present in the larval prawn. As a result of the removal of an axon, the most common effect found in central connections was the absence of the collaterals or axons deprived of their targets. No collateral sprouting was detected in the central nervous system. In about a third of the ganglia where a giant motoneuron was killed and structure was analyzed 2 or more weeks after irradiation, anomalous connections were found. They usually involved contacts between an interneuron deprived of its normal target and the contralateral motoneuron which remained intact. The restricted types of anomalies observed support the notion of a hierarchical order in the rules governing formation of central synapses, in which neuron type ranks higher than laterality. PMID:7062104

Friedlander, D R; Levinthal, C

1982-02-01

140

Monodon baculovirus of shrimp.  

PubMed

Among the viruses infecting penaeid shrimp, monodon-type baculovirus (MBV) otherwise known as Penaeus monodon singly enveloped nuclear polyhedrosis virus (PmSNPV), is one of the widely reported and well described viruses. It is a rod-shaped, enveloped, double-stranded DNA virus, and considered till recently, as the type A baculovirus. Besides MBV, two strains of SNPV are reported-plebejus baculovirus and bennettae baculovirus. MBV was reported to be originated from Taiwan and has wide geographic distribution and is reported to be enzootic in wild penaeids of the Indo-pacific coasts of Asia. The virus also has diverse host-range including a variety of cultured and captured shrimp species and freshwater prawn, Macrobrachium rosenbergii. MBV has been reported in all life stages of P. monodon with late larval, postlarval and young juvenile as the most susceptible stages/ages. However, MBV has not been documented in early larval stages. Although MBV has been reported to be tolerated well by shrimp, the infection has been attributed to decreased productivity. The target organs or tissues of MBV are the hepatopancreatic tubules and duct epithelium of postlarvae, juveniles and adults, and the anterior midgut epithelium of very young postlarvae. The prominent clinical sign of infection is the presence of multiple spherical inclusion bodies in the hepatopancreas and midgut epithelial cells. The major mode of transmission of the virus is horizontal through oral exposure to occlusion bodies, contaminated tissues or fomites. Minor morphometric variation of the virus has been reported among different isolates. The rod-shaped enveloped virus particles range from 265-324 nm in length and 42-77 nm in diameter. Although complete genome sequence of MBV is not available, nucleic acid of MBV is circular, double-stranded DNA with a genome size ranging from 80 to 160 kbp. The virus codes for a 53 kDa major polyhedrin polypeptide and two minor 47 and 49 kDa polypeptides. A variety of diagnostic tools have been reported for this virus including real-time PCR and LAMP-based detection. Taxonomic position is still uncertain and International Committee on Taxonomy of Viruses lists MBV as a tentative species named PemoNPV in the genus Nucleopolyhedrovirus. However, according to the latest genomic information on the virus, it has been suggested to create a new group of non-occluded bacilliform viruses called nudiviruses with MBV as one of the members. The aim of the current work is to describe the knowledge on the status, distribution and host-range, pathology, transmission, virus structure and morphogenesis, genomic characteristics, diagnosis and the latest taxonomic position of MBV. PMID:23997439

Rajendran, K V; Makesh, M; Karunasagar, I

2012-09-01

141

Cloning of crystallin from orange-spotted grouper and characterization of its activity as potential protective agent  

PubMed Central

Oxidative stress associated with nodavirus infection is poorly understood, especially pertaining to infection-mediated brain injury. Indirect evidence indicates that infection increases cellular abundance of reactive oxygen species (ROS) with consequent increase in cellular dityrosine production. The detection of dityrosine in nodavirus-infected grouper was demonstrated using immunohistochemical (IHC) staining. Proteomic analyses with eye tissues of healthy grouper revealed more abundant expression of crystallin protein in the eye than in various tissues, which was confirmed by real-time polymerase chain reaction and IHC analyses. Grouper crystallin belongs to a small heat shock protein family with chaperone-like function that prevents heat-induced and oxidative stress-induced protein aggregation. Recombinant crystallin induced nitric oxide (NO) production in RAW 264.7 cells after treatment. The results provide new insight into the pathogenesis of nodavirus and demonstrate an experimental rationale for antioxidant therapy research. PMID:24371554

Chen, Young-Mao; Kuo, Cham-En; Lin, Chun-Mao; Shie, Pei-Shiuan; Chen, Tzong-Yueh

2011-01-01

142

SPECIES INTERACTIONS BETWEEN ESTUARINE DETRITIVORES: INHIBITION OR FACILITATION?  

EPA Science Inventory

Native Hawaiian estuarine detritivores; the prawn Macrobrachium grandimanus, and the neritid gastropod Neritina vespertina, were maintained in flow-through microcosms with conditioned leaves from two riparian tree species, Hau (Hibiscus tiliaceus) and guava (Psidium guajava). Th...

143

Differential segregation of nodaviral coat protein and RNA into progeny virions during mixed infection with FHV and NoV.  

PubMed

Nodaviruses are icosahedral viruses with a bipartite, positive-sense RNA genome. The two RNAs are packaged into a single virion by a poorly understood mechanism. We chose two distantly related nodaviruses, Flock House virus and Nodamura virus, to explore formation of viral reassortants as a means to further understand genome recognition and encapsidation. In mixed infections, the viruses were incompatible at the level of RNA replication and their coat proteins segregated into separate populations of progeny particles. RNA packaging, on the other hand, was indiscriminate as all four viral RNAs were detectable in each progeny population. Consistent with the trans-encapsidation phenotype, fluorescence in situ hybridization of viral RNA revealed that the genomes of the two viruses co-localized throughout the cytoplasm. Our results imply that nodaviral RNAs lack rigorously defined packaging signals and that co-encapsidation of the viral RNAs does not require a pair of cognate RNA1 and RNA2. PMID:24725955

Gopal, Radhika; Venter, P Arno; Schneemann, Anette

2014-04-01

144

Nodamura Virus RNA Replication in Saccharomyces cerevisiae: Heterologous Gene Expression Allows Replication-Dependent Colony Formation  

Microsoft Academic Search

Nodamura virus (NoV) and Flock House virus (FHV) are members of the family Nodaviridae. The nodavirus genome is composed of two positive-sense RNA segments: RNA1 encodes the viral RNA-dependent RNA polymerase and RNA2 encodes the capsid protein precursor. A small subgenomic RNA3, which encodes nonstructural proteins B1 and B2, is transcribed from RNA1 during RNA replication. Previously, FHV was shown

B. Duane Price; Lance D. Eckerle; L. Andrew Ball; Kyle L. Johnson

2005-01-01

145

The Freshwater Shrimps Of Curaçao, West Indies (decapoda, Caridea)  

Microsoft Academic Search

On the basis of a é eld survey and review of existing records I here report on the occurrence of ten freshwater shrimp species in Curaç ao. Four species constitute new and\\/or previously unpublished records for the island. Existing records for the neighbouring islands of Bonaire and Aruba are reviewed. The most common species are Macrobrachium carcinus , M. crenulatum,

Adolphe O. Debrot

2003-01-01

146

The development of behavioral defenses: a mechanistic analysis of vulnerability in red-eyed tree frog hatchlings  

Microsoft Academic Search

I examined the development and effectiveness of behavioral defenses of red-eyed tree frog hatchlings, Agalychnis callidryas, against predatory shrimp Macrobrachium americanum. Arboreal eggs of A. callidryas hatch early if attacked by egg predators and later if undisturbed, producing tadpoles that enter the water at different developmental stages. Older hatchlings survive better than young hatchlings with aquatic predators, including shrimp. Hatchlings

Karen M. Warkentin

1999-01-01

147

Optimisation of Lime-Soda process parameters for reduction of hardness in aqua-hatchery practices using Taguchi methods.  

PubMed

This paper presents the optimisation of Lime-Soda process parameters for the reduction of hardness in aqua-hatchery practices in the context of M. rosenbergii. The fresh water in the development of fisheries needs to be of suitable quality. Lack of desirable quality in available fresh water is generally the confronting restraint. On the Indian subcontinent, groundwater is the only source of raw water, having varying degree of hardness and thus is unsuitable for the fresh water prawn hatchery practices (M. rosenbergii). In order to make use of hard water in the context of aqua-hatchery, Lime-Soda process has been recommended. The efficacy of the various process parameters like lime, soda ash and detention time, on the reduction of hardness needs to be examined. This paper proposes to determine the parameter settings for the CIFE well water, which is pretty hard by using Taguchi experimental design method. Orthogonal Arrays of Taguchi, Signal-to-Noise Ratio, the analysis of variance (ANOVA) have been applied to determine their dosage and analysed for their effect on hardness reduction. The tests carried out with optimal levels of Lime-Soda process parameters confirmed the efficacy of the Taguchi optimisation method. Emphasis has been placed on optimisation of chemical doses required to reduce the total hardness using Taguchi method and ANOVA, to suit the available raw water quality for aqua-hatchery practices, especially for fresh water prawn M. rosenbergii. PMID:24749379

Yavalkar, S P; Bhole, A G; Babu, P V Vijay; Prakash, Chandra

2012-04-01

148

Modern fauna and quantitative parameters of invasive invertebrates in zoobenthos of upper reaches of the Kuybyshev Reservoir, Russia  

Microsoft Academic Search

On the basis of data for the period 1998–2008, a faunistic review of invasive species of zoobenthos in the upper reaches of\\u000a the Kuybyshev Reservoir is given. In total, 30 species are revealed: polychaetes—3; oligochaetes—2; leeches—1; mollusks—5;\\u000a crustaceans—19 (gammarids—9; corophiums—2; cumaceans and mysids—3 each; narrow-clawed crayfish Astacus leptodactilus and shrimp Macrobrachium nipponense). Invasive species account for 10.8% of the total

A. V. Yakovleva; V. A. Yakovlev

2010-01-01

149

Nervous Necrosis Virus Replicates Following the Embryo Development and Dual Infection with Iridovirus at Juvenile Stage in Grouper  

PubMed Central

Infection of virus (such as nodavirus and iridovirus) and bacteria (such as Vibrio anguillarum) in farmed grouper has been widely reported and caused large economic losses to Taiwanese fish aquaculture industry since 1979. The multiplex assay was used to detect dual viral infection and showed that only nervous necrosis virus (NNV) can be detected till the end of experiments (100% mortality) once it appeared. In addition, iridovirus can be detected in a certain period of rearing. The results of real-time PCR and in situ PCR indicated that NNV, in fact, was not on the surface of the eggs but present in the embryo, which can continue to replicate during the embryo development. The virus may be vertically transmitted by packing into eggs during egg development (formation) or delivering into eggs by sperm during fertilization. The ozone treatment of eggs may fail to remove the virus, so a new strategy to prevent NNV is needed. PMID:22563447

Hsu, Hao-Hsuan; Chen, Peng-Peng; Lee, Szu-Hsien; Chen, Young-Mao; Tsai, Tieh-Jung; Wang, Chien-Kai; Ku, Hsiao-Tung; Lee, Gwo-Bin; Chen, Tzong-Yueh

2012-01-01

150

Rapid Evolution of Virus Sequences in Intrinsically Disordered Protein Regions  

PubMed Central

Nodamura Virus (NoV) is a nodavirus originally isolated from insects that can replicate in a wide variety of hosts, including mammals. Because of their simplicity and ability to replicate in many diverse hosts, NoV, and the Nodaviridae in general, provide a unique window into the evolution of viruses and host-virus interactions. Here we show that the C-terminus of the viral polymerase exhibits extreme structural and evolutionary flexibility. Indeed, fewer than 10 positively charged residues from the 110 amino acid-long C-terminal region of protein A are required to support RNA1 replication. Strikingly, this region can be replaced by completely unrelated protein sequences, yet still produce a functional replicase. Structure predictions, as well as evolutionary and mutational analyses, indicate that the C-terminal region is structurally disordered and evolves faster than the rest of the viral proteome. Thus, the function of an intrinsically unstructured protein region can be independent of most of its primary sequence, conferring both functional robustness and sequence plasticity on the protein. Our results provide an experimental explanation for rapid evolution of unstructured regions, which enables an effective exploration of the sequence space, and likely function space, available to the virus. PMID:25502394

Gitlin, Leonid; Hagai, Tzachi; LaBarbera, Anthony; Solovey, Mark; Andino, Raul

2014-01-01

151

Targeting of Dicer-2 and RNA by a Viral RNA Silencing Suppressor in Drosophila Cells  

PubMed Central

RNA interference (RNAi) is a eukaryotic gene-silencing mechanism that functions in antiviral immunity in diverse organisms. To combat RNAi-mediated immunity, viruses encode viral suppressors of RNA silencing (VSRs) that target RNA and protein components in the RNAi machinery. Although the endonuclease Dicer plays key roles in RNAi immunity, little is known about how VSRs target Dicer. Here, we show that the B2 protein from Wuhan nodavirus (WhNV), the counterpart of Flock House virus (FHV), suppresses Drosophila melanogaster RNAi by directly interacting with Dicer-2 (Dcr-2) and sequestering double-stranded RNA (dsRNA) and small interfering RNA (siRNA). Further investigations reveal that WhNV B2 binds to the RNase III and Piwi-Argonaut-Zwille (PAZ) domains of Dcr-2 via its C-terminal region, thereby blocking the activities of Dcr-2 in processing dsRNA and incorporating siRNA into the RNA-induced silencing complex (RISC). Moreover, we uncover an interrelationship among diverse activities of WhNV B2, showing that RNA binding enhances the B2–Dcr-2 interaction by promoting B2 homodimerization. Taken together, our findings establish a model of suppression of Drosophila RNAi by WhNV B2 targeting both Dcr-2 and RNA and provide evidence that an interrelationship exists among diverse activities of VSRs to antagonize RNAi. PMID:22438534

Qi, Nan; Zhang, Lei; Qiu, Yang; Wang, Zhaowei; Si, Jie; Liu, Yongxiang; Xiang, Xue; Xie, Jiazheng; Qin, Cheng-Feng; Hu, Yuanyang

2012-01-01

152

Rapid evolution of virus sequences in intrinsically disordered protein regions.  

PubMed

Nodamura Virus (NoV) is a nodavirus originally isolated from insects that can replicate in a wide variety of hosts, including mammals. Because of their simplicity and ability to replicate in many diverse hosts, NoV, and the Nodaviridae in general, provide a unique window into the evolution of viruses and host-virus interactions. Here we show that the C-terminus of the viral polymerase exhibits extreme structural and evolutionary flexibility. Indeed, fewer than 10 positively charged residues from the 110 amino acid-long C-terminal region of protein A are required to support RNA1 replication. Strikingly, this region can be replaced by completely unrelated protein sequences, yet still produce a functional replicase. Structure predictions, as well as evolutionary and mutational analyses, indicate that the C-terminal region is structurally disordered and evolves faster than the rest of the viral proteome. Thus, the function of an intrinsically unstructured protein region can be independent of most of its primary sequence, conferring both functional robustness and sequence plasticity on the protein. Our results provide an experimental explanation for rapid evolution of unstructured regions, which enables an effective exploration of the sequence space, and likely function space, available to the virus. PMID:25502394

Gitlin, Leonid; Hagai, Tzachi; LaBarbera, Anthony; Solovey, Mark; Andino, Raul

2014-12-01

153

First report of viral nervous necrosis-induced mass mortality in hatchery-reared larvae of clownfish, Amphiprion sebae Bleeker.  

PubMed

Frequent mortality was observed in the larval rearing facility of marine clownfish, Amphiprion sebae Bleeker. Mortality resulted in 80% loss of larval stock. Moribund larvae showed clinical signs typical of viral nervous necrosis, such as uncoordinated, corkscrew-like swimming behaviour, hypersensitivity to stimuli, darkening of body and assembly into large groups, similar to bunches of grapes. The aetiology of the disease was confirmed by gross observation of clinical signs, histopathology and molecular diagnosis. Histological studies revealed severe vacuolation in the brain and in the bipolar and ganglion layers of the eye. Molecular diagnosis by reverse transcription-polymerase chain reaction (RT-PCR) specific to piscine nodavirus yielded a positive result. The partial nucleotide sequences of the PCR-amplified fragment were 97-98% similar to other betanodavirus isolates reported globally and more closely aligned with red-spotted grouper nervous necrosis virus (RGNNV). This is the first report of susceptibility of clownfish, A. sebae, to betanodavirus and the presence of the RGNNV in India. PMID:24117972

Binesh, C P; Renuka, K; Malaichami, N; Greeshma, C

2013-12-01

154

Differential expression profiling of orange-spotted grouper larvae, Epinephelus coioides (Hamilton), that survived a betanodavirus outbreak.  

PubMed

Nervous necrosis virus (NNV), a piscine nodavirus, has caused serious viral nervous necrosis and viral encephalopathy and retinopathy in hatchery-reared larvae and juveniles of a wide range of marine teleost species worldwide in the last two decades. Although the mortality of NNV-infected larvae is nearly 100%, there are still some larvae that survive this catastrophe. To comprehensively understand the variations of these survivors at the molecular level, we collected orange-spotted grouper larvae that survived an NNV outbreak in an indoor hatchery in southern Taiwan to study differential gene expression. Healthy larvae with high, medium and low levels of detected NNV were compared with morbid larvae using a 9600-clone-containing grouper larva cDNA microarray, and differential gene expression was further confirmed by a quantitative real-time polymerase chain reaction. Significant variation exists in healthy larvae. The following genes were upregulated: adenylate kinase 1-2, myosin binding protein H-like, myosin light chain 2, myosin light chain 3, tropomyosin, fast/white muscle troponin T embryonic isoform, and parvalbumin 1 and 2 genes. The following genes were downregulated: apolipoprotein A-I, trypsinogen, pyruvate kinase and astacin-like metalloprotease. Moreover, immunoglobulin M heavy chain gene transcription was significantly higher in healthy larvae that had high virus levels, indicating that humoral immunity might protect organisms from viral infection. These results suggest that some non-immune-related genes may have played important roles in survival during the larval metamorphosis stage, after betanodavirus infection. PMID:22324345

Wu, M-S; Chen, C-W; Lin, C-H; Tzeng, C-S; Chang, C-Y

2012-03-01

155

Identification of novel positive-strand RNA viruses by metagenomic analysis of archaea-dominated Yellowstone hot springs.  

PubMed

There are no known RNA viruses that infect Archaea. Filling this gap in our knowledge of viruses will enhance our understanding of the relationships between RNA viruses from the three domains of cellular life and, in particular, could shed light on the origin of the enormous diversity of RNA viruses infecting eukaryotes. We describe here the identification of novel RNA viral genome segments from high-temperature acidic hot springs in Yellowstone National Park in the United States. These hot springs harbor low-complexity cellular communities dominated by several species of hyperthermophilic Archaea. A viral metagenomics approach was taken to assemble segments of these RNA virus genomes from viral populations isolated directly from hot spring samples. Analysis of these RNA metagenomes demonstrated unique gene content that is not generally related to known RNA viruses of Bacteria and Eukarya. However, genes for RNA-dependent RNA polymerase (RdRp), a hallmark of positive-strand RNA viruses, were identified in two contigs. One of these contigs is approximately 5,600 nucleotides in length and encodes a polyprotein that also contains a region homologous to the capsid protein of nodaviruses, tetraviruses, and birnaviruses. Phylogenetic analyses of the RdRps encoded in these contigs indicate that the putative archaeal viruses form a unique group that is distinct from the RdRps of RNA viruses of Eukarya and Bacteria. Collectively, our findings suggest the existence of novel positive-strand RNA viruses that probably replicate in hyperthermophilic archaeal hosts and are highly divergent from RNA viruses that infect eukaryotes and even more distant from known bacterial RNA viruses. These positive-strand RNA viruses might be direct ancestors of RNA viruses of eukaryotes. PMID:22379100

Bolduc, Benjamin; Shaughnessy, Daniel P; Wolf, Yuri I; Koonin, Eugene V; Roberto, Francisco F; Young, Mark

2012-05-01

156

Identification of Novel Positive-Strand RNA Viruses by Metagenomic Analysis of Archaea-Dominated Yellowstone Hot Springs  

SciTech Connect

There are no known RNA viruses that infect Archaea. Filling this gap in our knowledge of viruses will enhance our understanding of the relationships between RNA viruses from the three domains of cellular life and, in particular, could shed light on the origin of the enormous diversity of RNA viruses infecting eukaryotes. We describe here the identification of novel RNA viral genome segments from high-temperature acidic hot springs in Yellowstone National Park in the United States. These hot springs harbor low-complexity cellular communities dominated by several species of hyperthermophilic Archaea. A viral metagenomics approach was taken to assemble segments of these RNA virus genomes from viral populations isolated directly from hot spring samples. Analysis of these RNA metagenomes demonstrated unique gene content that is not generally related to known RNA viruses of Bacteria and Eukarya. However, genes for RNA-dependent RNA polymerase (RdRp), a hallmark of positive-strand RNA viruses, were identified in two contigs. One of these contigs is approximately 5,600 nucleotides in length and encodes a polyprotein that also contains a region homologous to the capsid protein of nodaviruses, tetraviruses, and birnaviruses. Phylogenetic analyses of the RdRps encoded in these contigs indicate that the putative archaeal viruses form a unique group that is distinct from the RdRps of RNA viruses of Eukarya and Bacteria. Collectively, our findings suggest the existence of novel positive-strand RNA viruses that probably replicate in hyperthermophilic archaeal hosts and are highly divergent from RNA viruses that infect eukaryotes and even more distant from known bacterial RNA viruses. These positive-strand RNA viruses might be direct ancestors of RNA viruses of eukaryotes.

Benjamin Bolduc; Daniel P. Shaughnessy; Yuri I. Wolf; Eugene V. Koonin; Francisco F. Roberto; Mark Young

2012-05-01

157

Evaluation of cells and biological reagents for adventitious agents using degenerate primer PCR and massively parallel sequencing.  

PubMed

We employed a massively parallel sequencing (MPS)-based approach to test reagents and model cell substrates including Chinese hamster ovary (CHO), Madin-Darby canine kidney (MDCK), African green monkey kidney (Vero), and High Five insect cell lines for adventitious agents. RNA and DNA were extracted either directly from the samples or from viral capsid-enriched preparations, and then subjected to MPS-based non-specific virus detection with degenerate oligonucleotide primer (DOP) PCR. MPS by 454, Illumina MiSeq, and Illumina HiSeq was compared on independent samples. Virus detection using these methods was reproducibly achieved. Unclassified sequences from CHO cells represented cellular sequences not yet submitted to the databases typically used for sequence identification. The sensitivity of MPS-based virus detection was consistent with theoretically expected limits based on dilution of virus in cellular nucleic acids. Capsid preparation increased the number of viral sequences detected. Potential viral sequences were detected in several samples; in each case, these sequences were either artifactual or (based on additional studies) shown not to be associated with replication-competent viruses. Virus-like sequences were more likely to be identified in BLAST searches using virus-specific databases that did not contain cellular sequences. Detected viral sequences included previously described retrovirus and retrovirus-like sequences in CHO, Vero, MDCK and High Five cells, and nodavirus and endogenous bracovirus sequences in High Five insect cells. Bovine viral diarrhea virus, bovine hokovirus, and porcine circovirus sequences were detected in some reagents. A recently described parvo-like virus present in some nucleic acid extraction resins was also identified in cells and extraction controls from some samples. The present study helps to illustrate the potential for MPS-based strategies in evaluating the presence of viral nucleic acids in various sample types, including cell culture substrates and vaccines. PMID:25454874

McClenahan, Shasta D; Uhlenhaut, Christine; Krause, Philip R

2014-12-12

158

Silencing of Host Genes Directed by Virus-Derived Short Interfering RNAs in Caenorhabditis elegans  

PubMed Central

Small interfering RNAs (siRNAs) processed from viral replication intermediates by RNase III-like enzyme Dicer guide sequence-specific antiviral silencing in fungi, plants, and invertebrates. In plants, virus-derived siRNAs (viRNAs) can target and silence cellular transcripts and, in some cases, are responsible for the induction of plant diseases. Currently it remains unclear whether viRNAs are also capable of modulating the expression of cellular genes in the animal kingdom, although animal virus-encoded microRNAs (miRNAs) are known to guide efficient silencing of host genes, thereby facilitating virus replication. In this report, we showed that viRNAs derived from a modified nodavirus triggered potent silencing of homologous cellular transcripts produced by the endogenous gene or transgene in the nematode worm Caenorhabditis elegans. Like that found in plants, virus-induced gene silencing (VIGS) in C. elegans also involves RRF-1, a worm RNA-dependent RNA polymerase (RdRP) that is known to produce single-stranded secondary siRNAs in a Dicer-independent manner. We further demonstrated that VIGS in C. elegans is inheritable, suggesting that VIGS has the potential to generate profound epigenetic consequences in future generations. Altogether, these findings, for the first time, confirmed that viRNAs have the potential to modulate host gene expression in the animal kingdom. Most importantly, the success in uncoupling the trigger and the target of the antiviral silencing would allow for the exploration of novel features of virus-host interactions mediated by viRNAs in the animal kingdom. PMID:22896621

Guo, Xunyang; Li, Wan-Xiang

2012-01-01

159

Isolation, Propagation, Characterization, Cryopreservation, and Application of Novel Cardiovascular Endothelial Cell Line From Channa striatus (Bloch, 1793).  

PubMed

There are only few primary endothelial cell cultures developed from fishes to date, but in this work the development of an endothelial cell line from Channa striatus is described. The vascular explants were plated into fibronectin (5 µg ml(-1)) and anti-CD31 antibody (100 ng ml(-1))-coated flask; after 60 h incubation explants were removed from the flask. The flask contained only endothelial and blood cells. Blood cells were cleared out after subsequent passages. The culture medium used was Leibovitz's L-15 supplemented with 20 % serum and antibiotics. The cultures were incubated at 28 °C in a normal atmosphere incubator. The plating efficiency was high (53.72 %). The endothelial cells were cryopreserved at different passage levels and revived successfully with 75-85 % survival. Polymerase chain reaction amplification of mitochondrial 16S rRNA using primer specific to C. striatus confirmed the origin of C. striatus cardiovascular endothelial (CSCVE) cell line from C. striatus. This cell line was further characterized for chromosome number, transfection, mycoplasma, cell cycle distribution, mitochondrial staining, and phagocytic activity. Cells were analyzed according to morphological appearance and expression of specific endothelial markers by fluorescent staining (von Willebrand Factor, anti-platelet endothelial cell adhesion molecule-1, and anti-Endoglin). The formation of tubules in the Matrigel and endothelial co-cultured with fibroblast like cells was observed. The cytotoxicity of ciprofloxacin on the CSCVE cell line was determined by MTT, AB, and R-123 cytotoxicity end points. Susceptibility of CSCVE cell line to nodavirus was confirmed by cytopathic effect and reverse transcriptase-polymerase chain reaction. PMID:25194832

Abdul Majeed, S; Nambi, K S N; Taju, G; Sahul Hameed, A S

2014-09-01

160

Profiling of infection specific mRNA transcripts of the European seabass Dicentrarchus labrax  

PubMed Central

Background The European seabass (Dicentrarchus labrax), one of the most extensively cultured species in European aquaculture productions, is, along with the gilthead sea bream (Sparus aurata), a prospective model species for the Perciformes which includes several other commercially important species. Massive mortalities may be caused by bacterial or viral infections in intensive aquaculture production. Revealing transcripts involved in immune response and studying their relative expression enhances the understanding of the immune response mechanism and consequently also the creation of vaccines. The analysis of expressed sequence tags (EST) is an efficient and easy approach for gene discovery, comparative genomics and for examining gene expression in specific tissues in a qualitative and quantitative way. Results Here we describe the construction, analysis and comparison of a total of ten cDNA libraries, six from different tissues infected with V. anguillarum (liver, spleen, head kidney, gill, peritoneal exudates and intestine) and four cDNA libraries from different tissues infected with Nodavirus (liver, spleen, head kidney and brain). In total 9605 sequences representing 3075 (32%) unique sequences (set of sequences obtained after clustering) were obtained and analysed. Among the sequences several immune-related proteins were identified for the first time in the order of Perciformes as well as in Teleostei. Conclusion The present study provides new information to the Gene Index of seabass. It gives a unigene set that will make a significant contribution to functional genomic studies and to studies of differential gene expression in relation to the immune system. In addition some of the potentially interesting genes identified by in silico analysis and confirmed by real-time PCR are putative biomarkers for bacterial and viral infections in fish. PMID:19361338

Sarropoulou, Elena; Sepulcre, Pilar; Poisa-Beiro, Laura; Mulero, Victoriano; Meseguer, José; Figueras, Antonio; Novoa, Beatriz; Terzoglou, Vasso; Reinhardt, Richard; Magoulas, Antonios; Kotoulas, Georgios

2009-01-01

161

Isolation and characterization of a novel alphanodavirus  

PubMed Central

Background Nodaviridae is a family of non-enveloped isometric viruses with bipartite positive-sense RNA genomes. The Nodaviridae family consists of two genera: alpha- and beta-nodavirus. Alphanodaviruses usually infect insect cells. Some commercially available insect cell lines have been latently infected by Alphanodaviruses. Results A non-enveloped small virus of approximately 30 nm in diameter was discovered co-existing with a recombinant Helicoverpa armigera single nucleopolyhedrovirus (HearNPV) in Hz-AM1 cells. Genome sequencing and phylogenetic assays indicate that this novel virus belongs to the genus of alphanodavirus in the family Nodaviridae and was designated HzNV. HzNV possesses a RNA genome that contains two segments. RNA1 is 3038 nt long and encodes a 110 kDa viral protein termed protein A. The 1404 nt long RNA2 encodes a 44 kDa protein, which exhibits a high homology with coat protein precursors of other alphanodaviruses. HzNV virions were located in the cytoplasm, in association with cytoplasmic membrane structures. The host susceptibility test demonstrated that HzNV was able to infect various cell lines ranging from insect cells to mammalian cells. However, only Hz-AM1 appeared to be fully permissive for HzNV, as the mature viral coat protein essential for HzNV particle formation was limited to Hz-AM1 cells. Conclusion A novel alphanodavirus, which is 30 nm in diameter and with a limited host range, was discovered in Hz-AM1 cells. PMID:21682922

2011-01-01

162

Crystal structure of a nematode-infecting virus.  

PubMed

Orsay, the first virus discovered to naturally infect Caenorhabditis elegans or any nematode, has a bipartite, positive-sense RNA genome. Sequence analyses show that Orsay is related to nodaviruses, but molecular characterizations of Orsay reveal several unique features, such as the expression of a capsid-? fusion protein and the use of an ATG-independent mechanism for translation initiation. Here we report the crystal structure of an Orsay virus-like particle assembled from recombinant capsid protein (CP). Orsay capsid has a T = 3 icosahedral symmetry with 60 trimeric surface spikes. Each CP can be divided into three regions: an N-terminal arm that forms an extended protein interaction network at the capsid interior, an S domain with a jelly-roll, ?-barrel fold forming the continuous capsid, and a P domain that forms surface spike projections. The structure of the Orsay S domain is best aligned to T = 3 plant RNA viruses but exhibits substantial differences compared with the insect-infecting alphanodaviruses, which also lack the P domain in their CPs. The Orsay P domain is remotely related to the P1 domain in calicivirus and hepatitis E virus, suggesting a possible evolutionary relationship. Removing the N-terminal arm produced a slightly expanded capsid with fewer nucleic acids packaged, suggesting that the arm is important for capsid stability and genome packaging. Because C. elegans-Orsay serves as a highly tractable model for studying viral pathogenesis, our results should provide a valuable structural framework for further studies of Orsay replication and infection. PMID:25136116

Guo, Yusong R; Hryc, Corey F; Jakana, Joanita; Jiang, Hongbing; Wang, David; Chiu, Wah; Zhong, Weiwei; Tao, Yizhi J

2014-09-01

163

Molecular cloning, expression and functional analysis of ISG15 in orange-spotted grouper, Epinephelus coioides.  

PubMed

Interferon-stimulated gene 15 (ISG15) is an ubiquitin homolog that is significantly induced by type I interferons or viral infections. Groupers, Epinephelus spp. being maricultured in China and Southeast Asian countries, always suffer from virus infection, including iridovirus and nodavirus. To date, the roles of grouper genes, especially interferon related genes in virus infection remained largely unknown. Here, the ISG15 homolog (EcISG15) was cloned from grouper Epinephelus coioides and its immune response to Singapore grouper iridovirus (SGIV) and grouper nervous necrosis virus (GNNV) was investigated. The full-length EcISG15 cDNA was composed of 948 bp and encoded a polypeptide of 155 amino acids with 37-68% identity with the known ISG15 homologs from other fish species. Amino acid alignment analysis indicated that EcISG15 contained two ubiquitin-like (UBL) domains and an Ub-conjugation domain (LRGG). Expressional analysis showed that EcISG15 was dramatically induced by GNNV infection, poly I:C or poly dA-dT treatment, but no obvious changes were observed during SGIV infection. Immunofluorescence assay showed that EcISG15 localized mainly in the cytoplasm of grouper cells in response to poly I:C stimulation or GNNV infection, but not in mock or SGIV infected cells. Western blot analysis indicated that the ISGylation was absent in SGIV-infected cells, but significantly enhanced in GNNV-infected or poly I:C transfected cells, suggesting that EcISG15 might play different roles in SGIV and GNNV infection. Furthermore, overexpression of EcISG15 in vitro inhibited the transcription of GNNV genes significantly. Taken together, the results indicated that fish ISG15 might exert important roles against RNA virus infection. PMID:23403156

Huang, Xiaohong; Huang, Youhua; Cai, Jia; Wei, Shina; Ouyang, Zhengliang; Qin, Qiwei

2013-05-01

164

Photobacterium sanctipauli sp. nov. isolated from bleached Madracis decactis (Scleractinia) in the St Peter & St Paul Archipelago, Mid-Atlantic Ridge, Brazil.  

PubMed

Five novel strains of Photobacterium (A-394T, A-373, A-379, A-397 and A-398) were isolated from bleached coral Madracis decactis (scleractinian) in the remote St Peter & St Archipelago (SPSPA), Mid-Atlantic Ridge, Brazil. Healthy M. decactis specimens were also surveyed, but no strains were related to them. The novel isolates formed a distinct lineage based on the 16S rRNA, recA, and rpoA gene sequences analysis. Their closest phylogenetic neighbours were Photobacterium rosenbergii, P. gaetbulicola, and P. lutimaris, sharing 96.6 to 95.8% 16S rRNA gene sequence similarity. The novel species can be differentiated from the closest neighbours by several phenotypic and chemotaxonomic markers. It grows at pH 11, produces tryptophane deaminase, presents the fatty acid C18:0, but lacks C16:0 iso. The whole cell protein profile, based in MALDI-TOF MS, distinguished the strains of the novel species among each other and from the closest neighbors. In addition, we are releasing the whole genome sequence of the type strain. The name Photobacterium sanctipauli sp. nov. is proposed for this taxon. The G + C content of the type strain A-394(T) (= LMG27910(T) = CAIM1892(T)) is 48.2 mol%. PMID:25024905

Moreira, Ana Paula B; Duytschaever, Gwen; Chimetto Tonon, Luciane A; Fróes, Adriana M; de Oliveira, Louisi S; Amado-Filho, Gilberto M; Francini-Filho, Ronaldo B; De Vos, Paul; Swings, Jean; Thompson, Cristiane C; Thompson, Fabiano L

2014-01-01

165

Photobacterium sanctipauli sp. nov. isolated from bleached Madracis decactis (Scleractinia) in the St Peter & St Paul Archipelago, Mid-Atlantic Ridge, Brazil  

PubMed Central

Five novel strains of Photobacterium (A-394T, A-373, A-379, A-397 and A-398) were isolated from bleached coral Madracis decactis (scleractinian) in the remote St Peter & St Archipelago (SPSPA), Mid-Atlantic Ridge, Brazil. Healthy M. decactis specimens were also surveyed, but no strains were related to them. The novel isolates formed a distinct lineage based on the 16S rRNA, recA, and rpoA gene sequences analysis. Their closest phylogenetic neighbours were Photobacterium rosenbergii, P. gaetbulicola, and P. lutimaris, sharing 96.6 to 95.8% 16S rRNA gene sequence similarity. The novel species can be differentiated from the closest neighbours by several phenotypic and chemotaxonomic markers. It grows at pH 11, produces tryptophane deaminase, presents the fatty acid C18:0, but lacks C16:0 iso. The whole cell protein profile, based in MALDI-TOF MS, distinguished the strains of the novel species among each other and from the closest neighbors. In addition, we are releasing the whole genome sequence of the type strain. The name Photobacterium sanctipauli sp. nov. is proposed for this taxon. The G + C content of the type strain A-394T (= LMG27910T = CAIM1892T) is 48.2 mol%. PMID:25024905

Moreira, Ana Paula B.; Duytschaever, Gwen; Chimetto Tonon, Luciane A.; Fróes, Adriana M.; de Oliveira, Louisi S.; Amado-Filho, Gilberto M.; Francini-Filho, Ronaldo B.; De Vos, Paul; Swings, Jean; Thompson, Cristiane C.

2014-01-01

166

Photobacterium jeanii sp. nov., isolated from corals and zoanthids.  

PubMed

Four novel isolates (R-40508(T), R-40507, R-40903 and R-21419) were obtained from different cnidarian species (Phyllogorgia dilatata, Merulina ampliata and Palythoa caribaeorum) from different places in Brazil and Australia. The novel isolates formed a tight phylogenetic group based on 16S rRNA, recA, topA, ftsZ, mreB and rpoA gene sequences. Their closest phylogenetic neighbours were the type strains of Photobacterium leiognathi, P. rosenbergii and P. halotolerans, sharing 97.1-97.5?% 16S rRNA gene sequence similarity. DNA-DNA hybridization between a representative strain (R-40508(T)) and the type strains of these Photobacterium species revealed less than 20?% relatedness, showing that the new isolates belong to a novel species. Several phenotypic features allow the differentiation of the novel species from its closest phylogenetic neighbours. It has gelatinase and lipase activity and can utilize melibiose, but it cannot grow on 6?% NaCl. In addition, the novel species has the fatty acid iso-C(16?:?0), but lacks the fatty acids C(17?:?0), C(17?:?0) cyclo, iso-C(17?:?0), C(17?:?1)?8c and iso-C(17?:?1)?9c. The name Photobacterium jeanii sp. nov. is proposed for this species, with the type strain R-40508(T) (=LMG 25436(T) =CAIM 1817(T)). The G+C content of the type strain is 45.5mol%. PMID:20081016

Chimetto, Luciane A; Cleenwerck, Ilse; Thompson, Cristiane C; Brocchi, Marcelo; Willems, Anne; De Vos, Paul; Thompson, Fabiano L

2010-12-01

167

DDT and Derivatives in Indicator Species of the Aquatic Food Web of Rangsit Agricultural Area, Central Thailand  

PubMed Central

The presence of DDT and derivatives in the food web of freshwater ecosystems of Rangsit agricultural area, Pathum Thani Province, Thailand were investigated from June 2004 to May 2007. By using gas chromatography (GC) with micro electron capture detector (? ECD), DDT and derivatives in water, sediment, and fifteen indicator species i.e., 2 producers; Eichhornia crassipes and plankton (phyto- and zoo- plankton), an herbivore; Trichogaster microlepis (3) 3 omnivores; Trichogaster trichopterus, Oreochromis niloticus, and Puntius gonionotus, 6 carnivores; Channa striatus, Oxyeleotris marmoratus, Macrognathus siamensis, Parambassis siamensis, Anabas testudineus, and Pristolepis fasciatus, and 3 detritivores; Macrobrachium lanchesteri, Pomacea sp., and Filopaludina mertensi were measured. Results show low concentration levels (part per billion) of DDT & derivatives in each food web compartment i.e. water, sediment, aquatic plant, plankton, fish, and invertebrates. Magnification patterns, i.e. bioconcentration, bioaccumulation, and biomagnification, based on habitat and foraging behavior of selected freshwater species indicates that DDT & derivatives can accumulate and be magnified through the food chain from the lowest up to the highest trophic level. Therefore, the presence of residues and the evidence of magnification patterns can be observed as ecological indicators for evaluating ecological health risk. PMID:20161116

Siriwong, W.; Thirakhupt, K.; Sitticharoenchai, D.; Rohitrattana, J.; Thongkongowm, P.; Borjan, M.; Robson, M.

2009-01-01

168

Deriving Freshwater Quality Criteria for Iron, Lead, Nickel, and Zinc for Protection of Aquatic Life in Malaysia  

PubMed Central

Freshwater quality criteria for iron (Fe), lead (Pb), nickel (Ni), and zinc (Zn) were developed with particular reference to aquatic biota in Malaysia, and based on USEPA's guidelines. Acute toxicity tests were performed on eight different freshwater domestic species in Malaysia which were Macrobrachium lanchesteri (prawn), two fish: Poecilia reticulata and Rasbora sumatrana, Melanoides tuberculata (snail), Stenocypris major (ostracod), Chironomus javanus (midge larvae), Nais elinguis (annelid), and Duttaphrynus melanostictus (tadpole) to determine 96 h LC50 values for Fe, Pb, Ni, and Zn. The final acute value (FAV) for Fe, Pb, Ni, and Zn were 74.5, 17.0, 165, and 304.9??g L?1, respectively. Using an estimated acute-to-chronic ratio (ACR) of 8.3, the value for final chronic value (FCV) was derived. Based on FAV and FCV, a criterion maximum concentration (CMC) and a criterion continuous concentration (CCC) for Fe, Pb, Ni, and Zn that are 37.2, 8.5, 82.5, and 152.4??g?L?1 and 9.0, 2.0, 19.9, and 36.7??g?L?1, respectively, were derived. The results of this study provide useful data for deriving national or local water quality criteria for Fe, Pb, Ni, and Zn based on aquatic biota in Malaysia. Based on LC50 values, this study indicated that N. elinguis, M. lanchesteri, N. elinguis, and R. sumatrana were the most sensitive to Fe, Pb, Ni, and Zn, respectively. PMID:22919358

Shuhaimi-Othman, M.; Nadzifah, Y.; Nur-Amalina, R.; Umirah, N. S.

2012-01-01

169

On the Brain of a Crustacean: A Morphological Analysis of CaMKII Expression and Its Relation to Sensory and Motor Pathways  

PubMed Central

Calcium/calmodulin kinase II (CaMKII) is a Ca2+-activated enzyme that is abundant in vertebrate and invertebrate brains. However, its characterization is poorly addressed in the nervous system of crustaceans, and, to our knowledge, no studies have determined the microanatomical location of CaMKII in a crustacean species. In this study, we found labeling of CaMKII in the eyestalk and brain of the prawn Macrobrachium acanthurus, by means of immunohistochemistry and Western blotting. Antibodies against neuron (ß tubulin III), glutamate receptor (GluA1), and FMRFamide were used in order to further characterize the CaMKII-labeled cells in the brain. In the eyestalk, strong labeling with CaMKII was observed in the photoreceptors. These cells, especially in the rhabdom, were also reactive to anti-ß tubulin III, whereas the pigment cells were labeled with anti-CaMKII. GluA1 co-located with CaMKII in the photoreceptors. Also, CaMKII appeared in the same sites as FMRFamide in the deutocerebrum, including the olfactory lobe, and in the tritocerebrum, specifically in the antennular neuropil, indicating that the synaptic areas in these regions may be related to sensory-motor processing. In the brain, the identification of cells and regions that express CaMKII contributes to the understanding of the processing of neural connections and the modulating role of CaMKII in decapod crustaceans. PMID:23741406

Ammar, Dib; Nazari, Evelise M.

2013-01-01

170

On the brain of a crustacean: a morphological analysis of CaMKII expression and its relation to sensory and motor pathways.  

PubMed

Calcium/calmodulin kinase II (CaMKII) is a Ca(2+)-activated enzyme that is abundant in vertebrate and invertebrate brains. However, its characterization is poorly addressed in the nervous system of crustaceans, and, to our knowledge, no studies have determined the microanatomical location of CaMKII in a crustacean species. In this study, we found labeling of CaMKII in the eyestalk and brain of the prawn Macrobrachium acanthurus, by means of immunohistochemistry and Western blotting. Antibodies against neuron (ß tubulin III), glutamate receptor (GluA1), and FMRFamide were used in order to further characterize the CaMKII-labeled cells in the brain. In the eyestalk, strong labeling with CaMKII was observed in the photoreceptors. These cells, especially in the rhabdom, were also reactive to anti-ß tubulin III, whereas the pigment cells were labeled with anti-CaMKII. GluA1 co-located with CaMKII in the photoreceptors. Also, CaMKII appeared in the same sites as FMRFamide in the deutocerebrum, including the olfactory lobe, and in the tritocerebrum, specifically in the antennular neuropil, indicating that the synaptic areas in these regions may be related to sensory-motor processing. In the brain, the identification of cells and regions that express CaMKII contributes to the understanding of the processing of neural connections and the modulating role of CaMKII in decapod crustaceans. PMID:23741406

Ammar, Dib; Nazari, Evelise M; Müller, Yara M R; Allodi, Silvana

2013-01-01

171

Infectious Bronchitis Virus Generates Spherules from Zippered Endoplasmic Reticulum Membranes  

PubMed Central

ABSTRACT Replication of positive-sense RNA viruses is associated with the rearrangement of cellular membranes. Previous work on the infection of tissue culture cell lines with the betacoronaviruses mouse hepatitis virus and severe acute respiratory syndrome coronavirus (SARS-CoV) showed that they generate double-membrane vesicles (DMVs) and convoluted membranes as part of a reticular membrane network. Here we describe a detailed study of the membrane rearrangements induced by the avian gammacoronavirus infectious bronchitis virus (IBV) in a mammalian cell line but also in primary avian cells and in epithelial cells of ex vivo tracheal organ cultures. In all cell types, structures novel to IBV infection were identified that we have termed zippered endoplasmic reticulum (ER) and spherules. Zippered ER lacked luminal space, suggesting zippering of ER cisternae, while spherules appeared as uniform invaginations of zippered ER. Electron tomography showed that IBV-induced spherules are tethered to the zippered ER and that there is a channel connecting the interior of the spherule with the cytoplasm, a feature thought to be necessary for sites of RNA synthesis but not seen previously for membrane rearrangements induced by coronaviruses. We also identified DMVs in IBV-infected cells that were observed as single individual DMVs or were connected to the ER via their outer membrane but not to the zippered ER. Interestingly, IBV-induced spherules strongly resemble confirmed sites of RNA synthesis for alphaviruses, nodaviruses, and bromoviruses, which may indicate similar strategies of IBV and these diverse viruses for the assembly of RNA replication complexes. IMPORTANCE All positive-sense single-stranded RNA viruses induce rearranged cellular membranes, providing a platform for viral replication complex assembly and protecting viral RNA from cellular defenses. We have studied the membrane rearrangements induced by an important poultry pathogen, the gammacoronavirus infectious bronchitis virus (IBV). Previous work studying closely related betacoronaviruses identified double-membrane vesicles (DMVs) and convoluted membranes (CMs) derived from the endoplasmic reticulum (ER) in infected cells. However, the role of DMVs and CMs in viral RNA synthesis remains unclear because these sealed vesicles lack a means of delivering viral RNA to the cytoplasm. Here, we characterized structures novel to IBV infection: zippered ER and small vesicles tethered to the zippered ER termed spherules. Significantly, spherules contain a channel connecting their interior to the cytoplasm and strongly resemble confirmed sites of RNA synthesis for other positive-sense RNA viruses, making them ideal candidates for the site of IBV RNA synthesis. PMID:24149513

Maier, Helena J.; Hawes, Philippa C.; Cottam, Eleanor M.; Mantell, Judith; Verkade, Paul; Monaghan, Paul; Wileman, Tom; Britton, Paul

2013-01-01

172

Two Membrane-Associated Regions within the Nodamura Virus RNA-Dependent RNA Polymerase Are Critical for both Mitochondrial Localization and RNA Replication  

PubMed Central

ABSTRACT Viruses with positive-strand RNA genomes amplify their genomes in replication complexes associated with cellular membranes. Little is known about the mechanism of replication complex formation in cells infected with Nodamura virus. This virus is unique in its ability to lethally infect both mammals and insects. In mice and in larvae of the greater wax moth (Galleria mellonella), Nodamura virus-infected muscle cells exhibit mitochondrial aggregation and membrane rearrangement, leading to disorganization of the muscle fibrils on the tissue level and ultimately in hind limb/segment paralysis. However, the molecular basis for this pathogenesis and the role of mitochondria in Nodamura virus infection remains unclear. Here, we tested the hypothesis that Nodamura virus establishes RNA replication complexes that associate with mitochondria in mammalian cells. Our results showed that Nodamura virus replication complexes are targeted to mitochondria, as evidenced in biochemical, molecular, and confocal microscopy studies. More specifically, we show that the Nodamura virus RNA-dependent RNA polymerase interacts with the outer mitochondrial membranes as an integral membrane protein and ultimately becomes associated with functional replication complexes. These studies will help us to understand the mechanism of replication complex formation and the pathogenesis of Nodamura virus for mammals. IMPORTANCE This study will further our understanding of Nodamura virus (NoV) genome replication and its pathogenesis for mice. NoV is unique among the Nodaviridae in its ability to infect mammals. Here we show that NoV establishes RNA replication complexes (RCs) in association with mitochondria in mammalian cells. These RCs contain newly synthesized viral RNA and feature a physical interaction between mitochondrial membranes and the viral RNA-dependent RNA polymerase (RdRp), which is mediated by two membrane-associated regions. While the nature of the interaction needs to be explored further, it appears to occur by a mode distinct from that described for the insect nodavirus Flock House virus (FHV). The interaction of the NoV RdRp with mitochondrial membranes is essential for clustering of mitochondria into networks that resemble those described for infected mouse muscle and that are associated with fatal hind limb paralysis. This work therefore provides the first link between NoV RNA replication complex formation and the pathogenesis of this virus for mice. PMID:24696464

Gant, Vincent U.; Moreno, Stephanie; Varela-Ramirez, Armando

2014-01-01

173

Photobacterium panuliri sp. nov., an alkalitolerant marine bacterium isolated from eggs of spiny lobster, Panulirus penicillatus from Andaman Sea.  

PubMed

A facultative anaerobe, alkalitolerant, gram-negative marine bacterium strain LBS5(T), was isolated from eggs carried on the pleopods of female spiny lobster (Panulirus penicillatus) in Andaman Sea from a depth of 3.5 m. Heterotrophic growth was observed at 15-38 °C and pH 5.5-11. Optimum growth occurred at 28 °C and pH 7.5. It can grow in the presence of 0.5-7 % NaCl (w/v), and the optimal NaCl required for growth was 2-4 %. 16S rRNA gene sequence analysis revealed the strain LBS5(T) belongs to the genus Photobacterium and showed 99.6 % similarity with P. aquae AE6(T), 98.2 % with P. aphoticum M46(T), 97 % with P. rosenbergii CC1(T), 96.9 % with P. lutimaris DF-42(T), and 96.6 % with P. halotolerans MACL01(T). The DNA-DNA similarities between strains LBS5(T) with other closely related strains were well below 70 %. The DNA G + C content was 50.52 (±0.9) mol%. The major fatty acids were C16:1w7c/w6c, C18:1w6c/w7c, C16:0, C15:0 iso, C16:0 10-methyl/17:1 iso w9c, C17:0 iso. Polar lipids included a phosphatidylglycerol, a diphosphatidylglycerol, a phosphatidylethanolamine, and one unidentified lipid. Based on the polyphasic evidences, strain LBS5(T) represents a novel species of the genus Photobacterium for which Photobacterium panuliri sp. nov. is proposed. The type strain is LBS5(T) (=DSM 27646(T) = LMG 27617(T) = JCM 19199(T)). PMID:24962598

Deep, Kamal; Poddar, Abhijit; Das, Subrata K

2014-11-01

174

Resistance to the crayfish plague pathogen, Aphanomyces astaci, in two freshwater shrimps.  

PubMed

Aphanomyces astaci, the causal agent of the crayfish plague, has recently been confirmed to infect also freshwater-inhabiting crabs. We experimentally tested the resistance of freshwater shrimps, another important decapod group inhabiting freshwaters, to this pathogen. We exposed individuals of two Asian shrimp species, Macrobrachium dayanum and Neocaridina davidi, to zoospores of the pathogen strain isolated from Procambarus clarkii, a known A. astaci carrier likely to get into contact with shrimps. The shrimps were kept in separate vessels up to seven weeks; exuviae and randomly chosen individuals were sampled throughout the experiment. Shrimp bodies and exuviae were tested for A. astaci presence by a species-specific quantitative PCR. The results were compared with amounts of A. astaci DNA in an inert substrate to distinguish potential pathogen growth in live specimens from persisting spores or environmental DNA attached to their surface. In contrast to susceptible crayfish Astacus astacus, we did not observe mortality of shrimps. The amount of detected pathogen DNA was decreasing steadily in the inert substrate, but it was still detectable several weeks after zoospore addition, which should be considered in studies relying on molecular detection of A. astaci. Probably due to moulting, the amount of A. astaci DNA was decreasing in N. davidi even faster than in the inert substrate. In contrast, high pathogen DNA levels were detected in some non-moulting individuals of M. dayanum, suggesting that A. astaci growth may be possible in tissues of this species. Further experiments are needed to test for the potential of long-term A. astaci persistence in freshwater shrimp populations. PMID:25064254

Svoboda, J; Mruga?a, A; Kozubíková-Balcarová, E; Kouba, A; Diéguez-Uribeondo, J; Petrusek, A

2014-09-01

175

Evidence of rapid shifts in the trophic base of lotic predators using experimental dietary manipulations and assimilation-based analyses.  

PubMed

Assimilation-based techniques such as stoichiometric analysis, bulk tissue stable isotope analysis (SIA), fatty acid (FA) profiling and compound-specific SIA of FAs can be used to resolve ambiguities in consumer-resource relationships, but comparisons of their effectiveness are lacking. Feeding trials and concurrent application of these techniques were used to investigate the trophic base of two shrimps from Hong Kong streams: the atyid Caridina cantonensis, which is a primary consumer, and predatory Macrobrachium hainanense (Palaemonidae). Leaf litter and periphyton were fed to C. cantonensis (CC-LF and CC-PF, respectively) reared in the laboratory for 2 months, when C. cantonensis, that had fed on a mixed diet (CC-WC), were collected from the field. Atyids from each group (CC-LF, CC-PF and CC-WC) were fed to M. hainanense (MH-L, MH-P and MH-W, respectively) during a further 2-month trial, at the end of which M. hainanense were also collected from the field (MH-R). FA biomarkers present in CC-WC and CC-PF indicated that C. cantonensis depended primarily on autochthonous foods, and FA profiles of CC-WC were distinct from those of CC-LF. Differences in C/N ratios and isotope signatures of leaf litter and periphyton were not reflected in tissues of atyids or palaemonid predators. FA profiles of M. hainanense groups were similar, but FA stable C isotope ratio (delta(13)C) signatures of MH-R and MH-W were distinct from those of MH-L and leaf litter. FA delta(13)C signatures of MH-R were similar to those of MH-P and MH-W, indicating that autochthonous resources constituted the trophic base of production for this predator. This is the first study using compound-specific SIA to study stream food chains. Compound-specific SIA and FA profiling allowed accurate elucidation of consumer-resource relationships that were not revealed by stoichiometry or bulk tissue SIA. Compound-specific SIA was particularly sensitive for detecting rapid shifts in the predator trophic base. This tool will have wide applicability for investigating food webs in a range of ecosystems. PMID:19132399

Lau, Danny C P; Leung, Kenneth M Y; Dudgeon, David

2009-04-01