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651.
Kidney podocytes are highly specialized terminally differentiated cells that form the final barrier to urinary protein loss. Podocytes are a target for injury by metabolic, autoimmune, hereditary, inflammatory, and other stressors. Persistence of podocyte injury leads to podocyte death and loss, which results in progressive kidney damage and ultimately kidney failure. Dendrin is a dual compartment protein with proapoptotic signaling properties. Nuclear relocation of dendrin in response to glomerular injury promotes podocyte apoptosis. Here we show that Yes-associated protein (YAP), a downstream target of Hippo kinases and an inhibitor of apoptosis, is expressed in the nucleus of podocytes. The WW domains of YAP mediate the interaction with the PPXY motifs of dendrin. This interaction is functionally relevant because YAP binding to dendrin reduces dendrin-dependent, staurosporine-induced apoptosis in co-transfected HEK293 cells. Moreover gene silencing of YAP in podocytes increases adriamycin-induced podocyte apoptosis. It also increases staurosporine-induced caspase-3/7 activity, which is rescued by dendrin depletion in YAP knockdown cells. Our findings elucidate YAP binding to dendrin as a prosurvival mechanism. The antiapoptotic signaling properties of YAP in podocytes could hold significance in the quest for targeted therapeutics aimed at preventing podocyte loss.  相似文献   
652.
During exploratory surveys in the tributaries (Penganga and Satnala) of Godavari and (Bheema) Krishna basins, specimens of mahseer were collected. The morpho‐meristic characteristics of these specimens conformed to the taxonomic keys for Tor tor. The mitochondrial COI sequences of these specimens clustered with the T. tor specimens from the River Narmada and were distinct from the other mahseer such as T. khudree and T. mussullah, which are known to exist in the rivers of the region. This confirmed the distribution of T. tor in the rivers of peninsular India and indicated an extended distribution of the known range. The major predominating habitat characteristics of collection areas were cobbles mixed with gravel, and a riparian cover of shrubs and trees. The occurrence of fingerling size specimens in the river suggests that the species has adapted and is likely to have established self‐recruiting populations in these rivers.  相似文献   
653.
Host cell invasion by Plasmodium falciparum requires multiple molecular interactions between host receptors and parasite ligands. A family of parasite proteins, which contain the conserved thrombospondin structural repeat motif (TSR), has been implicated in receptor binding during invasion. In this study we have characterized the functional role of a TSR containing blood stage protein referred to as P. falciparum thrombospondin related apical merozoite protein (PfTRAMP). Both native and recombinant PfTRAMP bind untreated as well as neuraminidase, trypsin or chymotrypsin‐treated human erythrocytes. PfTRAMP is localized in the rhoptry bulb and is secreted during invasion. Adhesion of microneme protein EBA175 with its erythrocyte receptor glycophorin A provides the signal that triggers release of PfTRAMP from the rhoptries. Rabbit antibodies raised against PfTRAMP block erythrocyte invasion by P. falciparum suggesting that PfTRAMP plays an important functional role in invasion. Combination of antibodies against PfTRAMP with antibodies against microneme protein EBA175 provides an additive inhibitory effect against invasion. These observations suggest that targeting multiple conserved parasite ligands involved in different steps of invasion may provide an effective strategy forthe development of vaccines against blood stage malaria parasites.  相似文献   
654.
Genetics of control mechanisms that underlies sex differentiation in date palm is not known. Sex of the plants becomes known only at the time of first flowering, which takes around 5 years. In comparison, molecular diagnosis (if available/feasible) promises quick and reliable identification of sex types very early when plantlets are growing in seedbeds. To develop such an assay, genomic DNA from 45 individual plants (25 female and 20 male) belonging to different varieties of date palm was subjected to PCR amplification using 100 random amplified polymorphic DNA (RAPD) and 104 intersimple sequence repeat (ISSR) primers. Initially, two bulk genomic DNA samples (each made by pooling DNA from ten male and female plants, separately) were used. A primer showing sex-specific band in bulked samples was further used for amplification of the genomic DNA of the individual samples of that bulk. Only one RAPD primer, OPA-02, amplified a fragment of ~1.0 kb in all the individual samples of male genotypes, whereas this fragment was absent in all the female genotypes. This male-specific fragment was cloned and sequenced (GenBank accession no. JN123357), and a sequence-characterized amplified region (SCAR) primer pair was designed that amplified a 406-bp fragment in both female and male genotypes and a unique fragment of 354 bp in only male genotypes. The SCAR marker was further validated using 25 female and ten male date palm plants belonging to different varieties collected from different locations.  相似文献   
655.
ABSTRACT

Microbial mannanases have become biotechnologically important since they target the hydrolysis of complex polysaccharides of plant tissues into simple molecules like manno-oligosaccharides and mannoses. The role of mannanases in the paper and pulp industry is well established and recently they have found application in the food and feed technology, coffee extraction, oil drilling and detergent industry. Mannanses are enzymes produced mainly from microorganisms but mannanases produced from plants and animals have also been reported. Bacterial mannanases are mostly extracellular and can act in a wide range of pH and temperature, though acidic and neutral mannanases are more common. This review will focus on complex mannan structure and the microbial enzyme complex involved in its complete breakdown, mannanase sources, production conditions and their applications in the commercial sector. The reference to plant and animal mannanases has been made to complete the overview. However, the major emphasis of the review is on the microbial mannanases.  相似文献   
656.
Mitoxantrone is a promising antitumor drug having considerably reduced cardiotoxicity as compared to anthracyclines. Its binding to deoxyhexanucleotides sequence d-(ATCGAT)2 has been studied by proton and phosphorous-31 nuclear magnetic resonance spectroscopy. The stoichiometry reveals that 1:1 and 2:1 mitoxantrone-d(ATCGAT)2 complexes are formed in solution. Significant upfield shifts in 6H/7H, 2H/3H, 11NH, and 12NH protons (~.5?ppm) of mitoxantrone and T6NH imino protons (~.3?ppm) are observed. The phosphorous resonances do not shift significantly indicating that the base pairs do not open at any nucleotide step along the sequence of hexamer. Several inter-molecular Nuclear Overhauser Enhancement connectivities between mitoxantrone and hexanucleotide protons indicate that mitoxantrone chromophore stacks with terminal A1-T6 base pair and side chains involving 12CH2, 12NH, and 14OH protons are in close proximity of A1, T2, A5, and T6 bases. Absorption and emission spectra show red shift in wavelength maxima, which is characteristic of stacking interaction. At higher mitoxantrone to nucleic acid ratios, electrostatic interactions are dominant. The 2:1 drug/DNA stoichiometric structure obtained by restrained Molecular Dynamics simulations shows considerable distortions in backbone torsional angles and helicoidal parameters although structural fluctuations in 25?ps analysis of trajectory are found to be negligible. Mitoxantrone binds as a monomer at either or both ends of hexamer externally with side chains interacting specifically with DNA. The findings are relevant to the understanding of pharmacological action of drug.  相似文献   
657.
In this study, approximately 3.4 kb nucleotide sequence of caprine TLR7 (Toll-like receptor 7) gene was generated from twelve different Indian goat breeds belonging to different geographical regions. Goat TLR7 gene ORF (Open Reading Frame) was found to be 3141 nucleotides long coding for 1046 amino acids similar to sheep. The sequence analysis at nucleotide level revealed goat TLR7 having 99.5% homology with sheep, followed by other livestock species. Simple Modular Architecture Research Tool (SMART) was used for the structural analysis of goat TLR7 that showed the presence of 22 leucine rich repeats (LRRs) along with single Toll/interleukin-1 receptor (TIR) domains. TIR domain, when compared, was found to be similar in ruminant species, goat, sheep, cattle, and buffalo. The phylogenetic analysis also revealed grouping of all ruminant species together, goat being closer to sheep followed by cattle and buffalo. A total of 22 polymorphic sites were observed in TLR7 gene of 24 goats representing 12 different breeds, out of which 19 were present within the coding region and three in 3'UTR. Out of the seven nonsynonymous SNPs, two were in ectodomains and one in TIR domain. Overall our results indicate substantial variation within goat TLR7 gene, which could be exploited for association with disease susceptibility.  相似文献   
658.
659.
APOBEC3G (APO3G) is a cellular cytidine deaminase with potent antiviral activity. Initial studies of the function of APO3G demonstrated extensive mutation of the viral genome, suggesting a model in which APO3G's antiviral activity is due to hypermutation of the viral genome. Recent studies, however, found that deaminase-defective APO3G mutants transiently expressed in virus-producing cells exhibited significant antiviral activity, suggesting that the antiviral activity of APO3G could be dissociated from its deaminase activity. To directly compare the antiviral activities of wild-type (wt) and deaminase-defective APO3G, we used two approaches: (i) we titrated wt and deaminase-defective APO3G in transient-transfection studies to achieve similar levels of virus-associated APO3G and (ii) we constructed stable cell lines and selected clones expressing comparable amounts of wt and deaminase-defective APO3G. Viruses produced under these conditions were tested for viral infectivity. The results from the two approaches were consistent and suggested that the antiviral activity of deaminase-defective APO3G was significantly lower than that of wt APO3G. We conclude that efficient inhibition of vif-defective human immunodeficiency virus type 1 requires catalytically active APO3G.  相似文献   
660.
The present study evaluated the inhibitory effects of zinc on colonic antioxidant defense system and histoarchitecture during 1,2 dimethylhydrazine (DMH) induced colon carcinogenesis in male Sparque Dawley rats. The rats were segregated into four groups viz., normal control, DMH treated, zinc treated, DMH + zinc treated. Colon carcinogenesis was induced through weekly subcutaneous injections of DMH (30 mg/kg body weight) for 8 weeks. Zinc (in the form of zinc sulphate) was supplemented to rats at a dose level of 227 mg/l in drinking water, ad libitum for the entire duration of the study. Increased lipid peroxidation was accompanied by a decrease in reduced glutathione (GSH), glutathione reductase (GR), glutathione-s-transferase (GST), superoxide dismutase (SOD), and catalase. Administration of zinc to DMH treated rats significantly decreased the lipid peroxidation levels with simultaneous enhancement of GSH, GR, GST, SOD, and Catalase. Histopathological studies from DMH treated rats revealed disorganization of colonic histoarchitecture. However, zinc treatment to DMH treated rats greatly restored normalcy in the colonic histoarchitecture, with no apparent signs of abnormality. Energy Dispersive X-Ray Fluorescence (EDXRF) studies revealed a significant decrease in tissue concentrations of zinc in the colon following DMH treatment, which upon zinc supplementation were recovered to near normal levels. In conclusion, the results of this study suggest that zinc has a beneficial effect during the initiation of key events leading to the development of experimentally induced carcinogenesis.  相似文献   
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