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121.
The Asian rice gall midge, Orseolia oryzae Wood-Mason (Cecidomyiidae: Diptera) is a serious pest of wet season rice in South and Southeast Asia. Due to internal feeding habit and presence of biotypes of the pest, the most feasible way to control is breeding varieties resistant against multiple biotypes through marker-assisted breeding (MAB). But very few versatile co-dominant markers linked to the gall midge resistance genes are available. We used a set of F9 recombinant inbred lines (RILs) of the cross TN1/PTB10 and identified microsatellite markers for the gall midge resistance gene in cv. PTB10 on short arm of rice chromosome 8. Markers RM22550 and RM547 flank the gene at a distance of 0.9 and 1.9 cM, respectively. Amplification of the markers in gall midge resistant and susceptible cultivars showed that these markers can be successfully used in MAB for development of gall midge resistant varieties.  相似文献   
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Recent experiments using expression, immunolocalization, and cell culture approaches have provided leading insights into regulation of luteal angiogenesis by different growth factor systems and its role in the function of corpus luteum (CL) in buffalo. On the contrary, lymphangiogenesis and its regulation in the CL are still poorly understood. The aim of this study was to evaluate the expression and localization of lymphangiogenic factors (vascular endothelial growth factor [VEGF]-C and VEGFD), their receptor (VEGFR3), and lymphatic endothelial marker (LYVE1) in bubaline CL during different stages of the estrous cycle and to investigate functional role of VEGFC and VEGFD in luteal lymphangeogenesis. The mRNA and protein expression of VEGFC, VEGFD, and VEGFR3 was significantly greater in mid and late luteal phases, which correlated well with the expression of LYVE1. The lymphangiogenic factors were localized in luteal cells, exclusively in the cytoplasm. Immunoreactivity of VEGFC was greater during midluteal phase and that of VEGFD was greater during the mid and late luteal phases. Luteal cells were cultured in vitro and treated for different time duration (24, 48, and 72 hours) with VEGFC and VEGFD each at 50, 100, and 150 ng/mL concentration and VEGFC with VEGFD at 100 ng/mL concentration. The temporal increase in LYVE1 mRNA expression was significant (P < 0.05) in VEGFC and VEGFC with VEGFD treatment and no significant change was seen in VEGFD treatment. Thus, it seems likely that VEGFD itself has little role in lymphangiogenesis but along with VEGFC it might have a synergistic effect on VEGFR3 receptors for inducing lymphangiogenesis. In summary, the present study provided evidence that VEGFC and VEGFD, and their receptor VEGFR3, are expressed in bubaline CL and are localized exclusively in the cell cytoplasm, suggesting that these factors have a functional role in lymphangiogenesis of CL in buffalo.  相似文献   
125.
Cadmium (Cd) is a potential environmental phytotoxicant. The generation of reactive oxygen species (ROS) due to Cd stress is responsible for the induction of oxidative stress in plants. On the other hand, SNP, a NO donor is known to have effect on Cd-induced oxidative stress in plants. We evaluated the effect of NO on the regulation of Cd stress in the rice (Oryza sativa L.) variety MSE-9. Cd treatment was given in the form of 50, 100 and 200 ??M, whereas for interaction study, 100 ??M of Cd and 100 ??M of SNP were used. The result showed that Cd-induced oxidative stress in MSE-9 by generating ROS. However, when SNP was given with Cd stress, it was seen that SNP treatment regulated the stress metabolism in rice seedlings under Cd toxicity by generating NO. It can be said that the SNP in combination with Cd treatment might possess the way to protect rice seedlings under Cd stress.  相似文献   
126.
The in vitro culture system for spermatogonial stem cells (SSCs) is a powerful tool for exploring molecular mechanisms of male gametogenesis and gene manipulation. Very little information is available for fish SSC biology. Our aim was to isolate highly pure SSCs from the testis of commercially important farmed carp, Labeo rohita. The minced testis of L. rohita was dissociated with collagenase. Dissociated cells purified by two-step Ficoll gradient centrifugation followed by magnetic activated cell sorting (MACS) using Thy1.2 (CD90.2) antibody dramatically heightened recovery rate for spermatogonial cells. The purified cells were cultured in vitro conditions for more than two months in L-15 media containing 10% fetal bovine serum (FBS), 1% carp serum, and other nutrients. The proliferative cells were dividing as validated by 5-bromo-2′-deoxyuridine (BrdU) incorporation assay and formed colonies/clumps with the typical characteristics of SSCs A majority of enriched cell population represented a Vasa+, Pou5f1/pou5f1+, Ssea-1+, Tra-1-81+, plzf+, Gfrα1/gfrα1, and c-Kit/c-kit as detected by immunocytochemical and/or quantitative real-time polymerase chain reaction (RT-PCR) analyses. Thus, Thy1+ SSCs were enriched with greater efficiency from the mixed population of testicular cells of L. rohita. A population of enriched spermatogonial cells could be cultured in an undifferentiated state. The isolated SSCs could provide avenue for undertaking research on basic and applied reproductive biology.  相似文献   
127.
Insulin is the key regulator of glucose homeostasis in mammals, and glucose-stimulated insulin biosynthesis is essential for maintaining glucose levels in a narrow range in mammals. Glucose specifically promotes the translation of insulin in pancreatic β-islet, and the untranslated regions of insulin mRNA play a role in such regulation. Specific factors in the β-islets bind to the insulin 5' UTR and regulate its translation. In the present study we identify protein-disulfide isomerase (PDI) as a key regulator of glucose-stimulated insulin biosynthesis. We show that both in vitro and in vivo PDI can specifically associate with the 5' UTR of insulin mRNA. Immunodepletion of PDI from the islet extract results in loss of glucose-stimulated translation indicating a critical role for PDI in insulin biosynthesis. Similarly, transient overexpression of PDI resulted in specific translation activation by glucose. We show that the RNA binding activity of PDI is mediated through PABP. PDI catalyzes the reduction of the PABP disulfide bond resulting in specific binding of PABP to the insulin 5' UTR. We also show that glucose stimulation of the islets results in activation of a specific kinase that can phosphorylate PDI. These findings identify PDI and PABP as important players in glucose homeostasis.  相似文献   
128.
Recovery of metal value, especially from low-grade ores and overburden minerals using acidophilic bacteria through the process of bioleaching is an environmentally benign and commercially scalable biotechnology. In recent years, while the “OMICS” landscape has been witnessing extensive application of computational tools to understand and interpret global biological sequence data, a dedicated bioinformatic server for analysis of bacterial information in the context of its bioleaching ability is not available. We have developed an on-line Bacterial Bioleaching Protein Finder (BBProF) System, which rapidly identifies novel proteins involved in a bacterial bioleaching process and also performs phylogenetic analysis of 16S rRNA genes. BBProF uses the features of Asynchronous Java Script and XML (AJAX) to provide an efficient and fast user experience with minimal requirement of network bandwidth. In the input module the server accepts any bacterial or archaeal complete genome sequence in RAW format and provides a list of proteins involved in the microbial leaching process. BBProF web server is integrated with the European Bioinformatics Institute (EBI) web services such as BLAST for homology search and InterProScan for functional characterization of output protein sequences. Studying evolutionary relationship of bacterial strains of interest using Muscle and ClustalW2 phylogeny web services from EBI is another key feature of our server, where 16S rRNA gene sequences are considered as input through a JQUERY interface along with the sequences present in the BBProF database library. Complete genome sequences of 24 bioleaching microorganism characterized by genomic and physiological study in the laboratory and their respective 16S rRNA gene sequences were stored in the database of the BBProF library. To our knowledge BBProF is the first integrated bioinformatic web server that demonstrates its utility in identifying potential bioleaching bacteria. We hope that the server facilitate ongoing comparative genomic studies on of bioleaching microorganisms and also assist in identification and design of novel microbial consortia that are optimally efficient bioleaching agents.  相似文献   
129.
Insect Barcode Information System called as Insect Barcode Informática (IBIn) is an online database resource developed by the National Bureau of Agriculturally Important Insects, Bangalore. This database provides acquisition, storage, analysis and publication of DNA barcode records of agriculturally important insects, for researchers specifically in India and other countries. It bridges a gap in bioinformatics by integrating molecular, morphological and distribution details of agriculturally important insects. IBIn was developed using PHP/My SQL by using relational database management concept. This database is based on the client– server architecture, where many clients can access data simultaneously. IBIn is freely available on-line and is user-friendly. IBIn allows the registered users to input new information, search and view information related to DNA barcode of agriculturally important insects.This paper provides a current status of insect barcode in India and brief introduction about the database IBIn.

Availability

http://www.nabg-nbaii.res.in/barcode  相似文献   
130.
The genetic algorithm was used effectively to find the optimal values of eight process variables for the maximum laccase production by Daedalea flavida in a stationary culture. The algorithm was modified suitably to improve laccase production with 18 parallel experiments in 4 generations. A high enzyme titer of 65 % was achieved after the optimization and compared to the titer obtained before optimization. To study the effect of the surface immobilized growth on the enzyme production, the fungus was grown on three solid carriers. When cultured on polymer composite fibers, polyurethane foam, or steel wool, at least 2.5 times more biomass was produced, compared to the biomass produced in support-free growth. On the contrary, the mycelia grown on solid support produced much less laccase than non-adhering mycelia. Four parallel runs of batch-fed cultures were done, using the cell mass of D. flavida to evaluate the influence of four different volumes of medium exchanged on laccase production. For sustainable production of the enzyme, complete exchange of medium was favorable, where the laccase activity increased continuously in six consecutive cycles, though, 50 % exchange of medium produced the maximum laccase in terms of mean enzyme activity obtained in six cycles.  相似文献   
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