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41.
Male fertility is an orchestrated interplay of loci on the Y chromosome with a number of genes from across the other chromosomes. In this context, micro-deletions in the Y chromosome have been correlated with spermatogenic failure often leading to infertility. However, causes of infertility in the patients with the normal spermiogram have remained unclear and therefore pose another level of challenge. In the present study, we analyzed 64 STSs, studied different Y-linked genes and loci and conducted single nucleotide variant (SNV) analyses in 31 infertile males with normal spermiogram along with 67 normal fertile males (NFMs) to gain an insight into the organization of their Y chromosome. Further, employing quantitative real-time PCR (qPCR), we studied copy number variation of DYZ1 arrays and three genes and mutational status of SRY by direct sequence analyses. STS analyses of the AZFa, b and c regions in these patients showed known and new mutations. Further, copies of DAZ and BPY2 in the patients were found to be affected [Formula: see text] compared to those in NFMs. All the patients had normal copy number of the SRY however its sequence analysis (in silico) showed mutations in eight patients. In four of these eight patients, SRY mutations resulted into truncated proteins. Similarly, DYZ1 analysis showed micro-deletions and it's much reduced copy number [Formula: see text] as compared to those in NFMs. Present study in males with unexplained infertility revealed deletions similar to those observed in oligospermic and azoospermic patients. Thus, there are some common but still unknown factors underlying infertility in these patients irrespective of their spermatogenic status. This work is envisaged to augment DNA diagnosis, proving beneficial in the context of in vitro fertilization (IVF) and genetic counselling. 相似文献
42.
Anju Gulati Pat Schryer Alan McHughen 《In vitro cellular & developmental biology. Plant》2001,37(6):798-802
Summary A protocol for regeneration and micrografting of shoots of lentil (Lens culinaris Medik) was developed. Multiple shoots (4–5) were regenerated from cotyledonary node explants on Murashige and Skoog (MS)
medium containing 8.8 μM 6-benzylaminopurine. In vitro regenerated shoots were micrografted on rootstocks with 96% efficiency. The successful grafts were transplanted to pots in
Redi-earthTM, hardened off and were grown to maturity with 100% success. The success of the micrografting was independent of the nature
and concentration of growth regulator used in shoot initiation medium and the time period for induction of shoots. The protocol
was successful with several cultivars of lentil. The advantages of micrografting over in vitro rooting are discussed. 相似文献
43.
William A. Kronert Girish C. Melkani Anju Melkani Sanford I. Bernstein 《The Journal of biological chemistry》2014,289(18):12779-12790
Intramolecular communication within myosin is essential for its function as motor, but the specific amino acid residue interactions required are unexplored within muscle cells. Using Drosophila melanogaster skeletal muscle myosin, we performed a novel in vivo molecular suppression analysis to define the importance of three relay loop amino acid residues (Ile508, Asn509, and Asp511) in communicating with converter domain residue Arg759. We found that the N509K relay mutation suppressed defects in myosin ATPase, in vitro motility, myofibril stability, and muscle function associated with the R759E converter mutation. Through molecular modeling, we define a mechanism for this interaction and suggest why the I508K and D511K relay mutations fail to suppress R759E. Interestingly, I508K disabled motor function and myofibril assembly, suggesting that productive relay-converter interaction is essential for both processes. We conclude that the putative relay-converter interaction mediated by myosin residues 509 and 759 is critical for the biochemical and biophysical function of skeletal muscle myosin and the normal ultrastructural and mechanical properties of muscle. 相似文献
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46.
An Endoplasmic Reticulum Retrieval Signal Partitions Human Foamy Virus Maturation to Intracytoplasmic Membranes
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Paul A. Goepfert Kit Shaw George Wang Anju Bansal Bradley H. Edwards Mark J. Mulligan 《Journal of virology》1999,73(9):7210-7217
Among all retroviruses, foamy viruses (FVs) are unique in that they regularly mature at intracytoplasmic membranes. The envelope glycoprotein of FV encodes an endoplasmic reticulum (ER) retrieval signal, the dilysine motif (KKXX), that functions to localize the human FV (HFV) glycoprotein to the ER. This study analyzed the function of the dilysine motif in the context of infectious molecular clones of HFV that encoded mutations in the dilysine motif. Electron microscopy (EM) demonstrated virion budding both intracytoplasmically and at the plasma membrane for the wild-type and mutant viruses. Additionally, mutant viruses retained their infectivity, but viruses lacking the dilysine signal budded at the plasma membrane to a greater extent than did wild-type viruses. Interestingly, this relative increase in budding across the plasma membrane did not increase the overall release of viral particles into cell culture media as measured by protein levels in viral pellets or infectious virus titers. We conclude that the dilysine motif of HFV imposes a partial restriction on the site of viral maturation but is not necessary for viral infectivity. 相似文献
47.
Sporotrichum thermophile BJAMDU5 secreted high titres of xylanolytic and cellulolytic enzymes in solid state fermentation using mixture of wheat straw and cotton oil cake (ratio 1:1) at 45?°C, pH 5.0 after 72 h inoculated with 2.9?×?107 CFU/mL conidiospores. Supplementation of solid medium with lactose and ammonium sulphate further enhanced the production of hydrolytic enzymes. Among different surfactants studied, Tween 80 enhanced the production of all enzymes [3455 U/g DMR (dry mouldy residue), 879.26 U/g DMR, 976.28 U/g DMR and 35.10 U/g DMR for xylanase, CMCase (Carboxymethylcellulase), FPase (Filter paper activity) and β-glucosidase, respectively] as compared to other surfactants. Recycling of solid substrate reduced the production of all these enzymes after second cycle. End products analysis by TLC showed the ability of hydrolytic enzymes of S. thermophile to liberate monomeric (xylose and glucose) as well as oligomeric (xylobiose, cellobiose and higher ones) sugars. Supplementation of enzyme resulted in improved nutritional properties of the bread. Formation of oligomeric sugars by xylanase enzyme of S. thermophile BJAMDU5 make it a good candidate in food industry. 相似文献
48.
Manoj Kumar Kishu Ranjan Vijay Singh Chandramani Pathak Anju Pappachan Desh Deepak Singh 《The protein journal》2017,36(4):343-351
Hydrophilic acylated surface proteins (HASPs) are acidic surface proteins which get localized on the surface of Leishmania parasite during infective stages through a “non-classical” pathway. In this study, we report the heterologous expression and purification of Leishmania donovani HASPA (r-LdHASPA) in E. coli system and its partial characterization. The structural aspects of the purified protein were analyzed using CD spectroscopy and modeling studies which indicate that r-LdHASPA consists of random coils. Studies in mouse macrophage RAW264.7 cell lines indicate that r-LdHASPA enhances reactive oxygen species (ROS) production. Co-immunoprecipitation (IP) studies indicate that r-LdHASPA interacts with certain macrophage proteins which however could not be identified unambiguously. The present study provides key insights into the structural and functional aspects of an important Leishmania protein, HASPA, which we believe could be useful for further research on vaccine/drug development. 相似文献
49.
Four Plasmodium species cause malaria in humans: Plasmodium vivax is the most widespread and results in pronounced morbidity. India (population >1 billion) is a major contributor to the burden of vivax malaria. With a resurgence in interest concerning the neglected burden of vivax malaria and the completion of the P. vivax genome, it is timely to review what is known concerning P. vivax in India. The P. vivax population is highly diverse in terms of relapse patterns, drug response and clinical profiles, and highly genetically variable according to studies of antigen genes, isoenzyme markers and microsatellites. The unique epidemiology of malaria in India, where P. vivax predominates over Plasmodium falciparum, renders this location ideal for studying the dynamics of co-infection. 相似文献
50.
Identification of novel genes that modify phenotypes induced by Alzheimer's beta-amyloid overexpression in Drosophila
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Sustained increases in life expectancy have underscored the importance of managing diseases with a high incidence in late life, such as various neurodegenerative conditions. Alzheimer's disease (AD) is the most common among these, and consequently significant research effort is spent on studying it. Although a lot is known about the pathology of AD and the role of beta-amyloid (Abeta) peptides, the complete network of interactions regulating Abeta metabolism and toxicity still eludes us. To address this, we have conducted genetic interaction screens using transgenic Drosophila expressing Abeta and we have identified mutations that affect Abeta metabolism and toxicity. These analyses highlight the involvement of various biochemical processes such as secretion, cholesterol homeostasis, and regulation of chromatin structure and function, among others, in mediating toxic Abeta effects. Several of the mutations that we identified have not been linked to Abeta toxicity before and thus constitute novel potential targets for AD intervention. We additionally tested these mutations for interactions with tau and expanded-polyglutamine overexpression and found a few candidate mutations that may mediate common mechanisms of neurodegeneration. Our data offer insight into the toxicity of Abeta and open new areas for further study into AD pathogenesis. 相似文献