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51.
Tanuja Rana Anuradha Negi Sunny Dhir Tombisana Thockchom Vanita Chandel Yashika Walia 《Archives Of Phytopathology And Plant Protection》2013,46(6):505-512
Apple is known to be susceptible to various virus and viroid pathogens. Symptomatic apple cultivars and rootstocks were collected and analyzed by ELISA and then through RT-PCR. The study reports the presence of Apple mosaic virus (ApMV), Apple stem grooving virus (ASGV), Apple stem pitting virus (ASPV), Apple chlorotic leaf spot virus (ACLSV), the major apple viruses and Prunus necrotic ringspot virus (PNRSV), a minor apple virus, at the molecular level in India. Apple scar skin viroid (ASSVd) infection was also confirmed at the molecular level. Sporadic incidences of Tomato ringspot virus and Arabis mosaic virus infections were also detected by ELISA in nursery plants. 相似文献
52.
Sayed Sartaj Sohrab Zeenat Mirza Sajjad Karim Debashis Rana Adel M. Abuzenadah Adeel G. Chaudhary 《Archives Of Phytopathology And Plant Protection》2013,46(9):1047-1053
Leaf curl and yellow vein mosaic viral disease is the major constraint on okra (Abelmoschus esculentus L.) production in India. Amplified fragment sequence of DNA-β showed highest similarity of 91.7% with Bhendi yellow vein mosaic virus-Tamil Nadu (AJ308425, NC_003405) and lowest similarity of 48.5% with OKLCV (NC_004093), whereas coat protein specific amplified sequence showed highest homology with isolate of Madurai, Haryana, Ludhiana and lowest homology of 92% with Mesta yellow vein mosaic Bahraich virus (MYVMBV) (EU360303). The results obtained in the present study confirm that both the viral diseases of okra reported in southern India are caused by a begomovirus associated with DNA-β in which the plants show leaf curl symptoms and never develops yellow vein mosaic and those plants which show yellow vein mosaic, never develops leaf curl symptoms even in the same rows and field. The okra leaf curl is an emerging virus disease in India. 相似文献
53.
Stone fruits and pome fruits are cultivated commercially worldwide. In India, they are grown in temperate regions, which mainly includes Jammu and Kashmir, Uttarakhand, Himachal Pradesh and some North-Eastern states. In this study, an attempt has been made to identify the Prunus necrotic ringspot virus (PNRSV) infecting stone and pome fruits in India and to characterise them on the molecular level. Surveys were conducted in the temperate fruit-growing areas and incidence of PNRSV was detected by serological and molecular means in almond, apple, cherry, nectarine, peach, plum and wild cherry. Further diversity analysis of PNRSV was performed using bioinformatics tools such as clustalW, DNA Data Bank of Japan, MultAlin and Recombination Detection Programme. PNRSV was detected in plum, peach, cherry, almond, nectarine, wild cherry and apple. In the diversity analysis study on the basis of coat protein gene, it was found that the isolates showed identity levels from 82 to 100%. In a plum isolate, a stretch of amino acids from 207 to 221 was found variable from Indian and other isolates. In one of the Indian apple isolates, “NR” repeats at 41–44 position (characteristic of PV-32 group, Group I) were identified. Phylogenetic analysis revealed that Indian isolates are falling in Group-I. Movement protein was also amplified from peach and multiple alignment studies showed that N-terminus was mostly conserved, whereas the C-terminal was highly variable. 相似文献
54.
Vinay Singh Tanwar Mandeep P. Chand Jitender Kumar Gaurav Garg Sandeep Seth Ganesan Karthikeyan Shantanu Sengupta 《Gene》2013
Vitamin B12 is an essential micronutrient synthesized by microorganisms. Mammals including humans have evolved ways for transport and absorption of this vitamin. Deficiency of vitamin B12 (either due to low intake or polymorphism in genes involved in absorption and intracellular transport of this vitamin) has been associated with various complex diseases. Genome-wide association studies have recently identified several common single nucleotide polymorphisms (SNPs) in fucosyl transferase 2 gene (FUT2) to be associated with levels of vitamin B12—the strongest association was with a non-synonymous SNP rs602662 in this gene. In the present study, we attempted to replicate the association of this SNP (rs602662) in an Indian population since a significant proportion has been reported to have low levels of vitamin B12 in this population. A total of 1146 individuals were genotyped for this SNP using a single base extension method and association with levels of vitamin B12 was assessed in these individuals. Regression analysis was performed to analyze the association considering various confounding factors like for age, sex, diet, hypertension, diabetes mellitus and coronary artery disease status. We found that the SNP rs602662 was significantly associated with the levels of vitamin B12 (p value < 0.0001). We also found that individuals adhering to a vegetarian diet with GG (homozygous major genotype) have significantly lower levels of vitamin B12 in these individuals. Thus, our study reveals that vegetarian diet along with polymorphism in the FUT2 gene may contribute significantly to the high prevalence of vitamin B12 deficiency in India. 相似文献
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56.
With the rise of antibody based therapeutics as successful medicines, there is an emerging need to understand the fundamental antibody conformational dynamics and its implications towards stability of these medicines. Both deglycosylation and thermal stress have been shown to cause conformational destabilization and aggregation in monoclonal antibodies. Here, we study instabilities caused by deglycosylation and by elevated temperature (400 K) by performing molecular dynamic simulations on a full length murine IgG2a mAb whose crystal structure is available in the Protein Data bank. Cα‐atom root mean square deviation and backbone root mean square fluctuation calculations show that deglycosylation perturbs quaternary and tertiary structures in the CH2 domains. In contrast, thermal stress pervades throughout the antibody structure and both Fabs and Fc regions are destabilized. The thermal stress applied in this study was not sufficient to cause large scale unfolding within the simulation time and most amino acid residues showed similar average solvent accessible surface area and secondary structural conformations in all trajectories. CH3 domains were the most successful at resisting the conformational destabilization. The simulations helped identify aggregation prone regions, which may initiate cross‐β motif formation upon deglycosylation and upon applying thermal stress. Deglycosylation leads to increased backbone fluctuations and solvent exposure of a highly conserved APR located in the edge β‐strand A of the CH2 domains. Aggregation upon thermal stress is most likely initiated by two APRs that overlap with the complementarity determining regions. This study has important implications for rational design of antibody based therapeutics that are resistant towards aggregation. Proteins 2013. © 2012 Wiley Periodicals, Inc. 相似文献
57.
Sorghum with its remarkable adaptability to drought and high temperature provides a model system for grass genomics and resource for gene discovery especially for abiotic stress tolerance. Group 3 LEA genes from barley and rice have been shown to play crucial role in abiotic stress tolerance. Here, we present a genome-wide analysis of LEA3 genes in sorghum. We identified four genes encoding LEA3 proteins in the sorghum genome and further classified them into LEA3A and LEA3B subgroups based on the conservation of LEA3 specific motifs. Further, expression pattern of these genes were analyzed in seeds during development and vegetative tissues under abiotic stresses. SbLEA3A group genes showed expression at early stage of seed development and increased significantly at maturity, while SbLEA3B group genes expressed only in matured seeds. Expression of SbLEA3 genes in response to abiotic stresses such as soil moisture deficit (drought), osmotic, salt, and temperature stresses, and exogenous ABA treatments was also studied in the leaves of 2-weeks-old seedlings. ABA and drought induced the expression of all LEA3 genes, while cold and heat stress induced none of them. Promoter analysis revealed the presence of multiple ABRE core cis-elements and a few low temperature response (LTRE)/drought responsive (DRE) cis-elements. This study suggests non-redundant function of LEA3 genes in seed development and stress tolerance in sorghum. 相似文献
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59.
Arun T. John Peter Jens Lachmann Meenakshi Rana Madeleine Bunge Margarita Cabrera Christian Ungermann 《The Journal of cell biology》2013,201(1):97-111
Membrane microcompartments of the early endosomes serve as a sorting and signaling platform, where receptors are either recycled back to the plasma membrane or forwarded to the lysosome for destruction. In metazoan cells, three complexes, termed BLOC-1 to -3, mediate protein sorting from the early endosome to lysosomes and lysosome-related organelles. We now demonstrate that BLOC-1 is an endosomal Rab-GAP (GTPase-activating protein) adapter complex in yeast. The yeast BLOC-1 consisted of six subunits, which localized interdependently to the endosomes in a Rab5/Vps21-dependent manner. In the absence of BLOC-1 subunits, the balance between recycling and degradation of selected cargoes was impaired. Additionally, our data show that BLOC-1 is both a Vps21 effector and an adapter for its GAP Msb3. BLOC-1 and Msb3 interacted in vivo, and both mutants resulted in a redistribution of active Vps21 to the vacuole surface. We thus conclude that BLOC-1 controls the lifetime of active Rab5/Vps21 and thus endosomal maturation along the endocytic pathway. 相似文献
60.
Andreas D. Kistler Geetika Singh Mehmet M. Altintas Hao Yu Isabel C. Fernandez Changkyu Gu Cory Wilson Sandeep Kumar Srivastava Alexander Dietrich Katherina Walz Dontscho Kerjaschki Phillip Ruiz Stuart Dryer Sanja Sever Amit K. Dinda Christian Faul Jochen Reiser 《The Journal of biological chemistry》2013,288(51):36598-36609
Gain-of-function mutations in the calcium channel TRPC6 lead to autosomal dominant focal segmental glomerulosclerosis and podocyte expression of TRPC6 is increased in some acquired human glomerular diseases, particularly in membranous nephropathy. These observations led to the hypothesis that TRPC6 overactivation is deleterious to podocytes through pathological calcium signaling, both in genetic and acquired diseases. Here, we show that the effects of TRPC6 on podocyte function are context-dependent. Overexpression of TRPC6 alone did not directly affect podocyte morphology and cytoskeletal structure. Unexpectedly, however, overexpression of TRPC6 protected podocytes from complement-mediated injury, whereas genetic or pharmacological TRPC6 inactivation increased podocyte susceptibility to complement. Mechanistically, this effect was mediated by Ca2+/calmodulin-dependent protein kinase II (CaMKII) activation. Podocyte-specific TRPC6 transgenic mice showed stronger CaMKII activation, reduced podocyte foot process effacement and reduced levels of proteinuria during nephrotoxic serum nephritis, whereas TRPC6 null mice exhibited reduced CaMKII activation and higher levels of proteinuria compared with wild type littermates. Human membranous nephropathy biopsy samples showed podocyte staining for active CaMKII, which correlated with the degree of TRPC6 expression. Together, these data suggest a dual and context dependent role of TRPC6 in podocytes where acute activation protects from complement-mediated damage, but chronic overactivation leads to focal segmental glomerulosclerosis. 相似文献