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1.
Stage-dependent changes in localization of a germ cell-specific lamin during mammalian spermatogenesis 总被引:1,自引:0,他引:1
We had earlier identified a 110/120-kDa protein specific to nuclear matrix of rat pachytene spermatocytes (Behal, A., Prakash, K., and Rao, M.R.S. (1987) J. Biol. Chem. 262, 10898-10902). This protein is now shown to be a disulfide-linked homodimer of a 60-kDa polypeptide. Indirect immunofluorescence and Western blot analyses using anti-120-kDa polyclonal antibodies have shown that this protein is a component of the pore-complex lamina structure of spermatogonia. As germ cells enter meiotic prophase and the lamina structure disassembles, this polypeptide is redistributed in the nucleus and can be isolated as a component of synaptonemal complexes. Following meiotic division, this 60-kDa protein is relocalized in the lamina, then representing the sole major component of the lamina structure of round spermatids. The identity of the 60-kDa protein in the pore-complex lamina fraction and synaptonemal complexes was further confirmed by two-dimensional analysis of iodinated tryptic peptides. Such an analysis has also shown that the germ cell-specific 60-kDa protein is related but not identical to somatic lamin B. 相似文献
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Application of abscisic acid (ABA) brings about stomatal closure within 30 min in epidermal peels of Vicia faba . A number of phenolic compounds antagonise the effect of ABA. Derivatives of benzoic acid, cinnamic acid, coumarin and flavonoids have been studied in order to establish structure – activity relationship. Derivatives of benzoic acid reverse the ABA effects. Coumarin, esculetin and three hydro derivatives of cinnamic acid fail to show the anti-ABA activity. Thus, the presence of parahydroxyl group and double bond in the side chain is necessary for anti-ABA activity. 相似文献
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Palakolanu Sudhakar Reddy 《Analytical biochemistry》2008,381(2):248-253
We developed a PCR-based high-throughput genome-walking protocol. The novelty of this protocol is in the random introduction of unique walker primer binding sites into different regions of the genome efficiently by taking advantage of the rolling circle mode of DNA synthesis by Phi29 DNA polymerase after annealing the partially degenerate primers to the denatured genomic DNA. The inherent strand-displacement activity of the Phi29 DNA polymerase displaces the 5′ ends of downstream strands and DNA synthesis continues, resulting in a large number of overlapping fragments that cover the whole genome with the unique walker adapter attached to the 5′ end of all the genomic DNA fragments. The directional genome walking can be performed using a locus-specific primer and the walker primer and Phi29 DNA polymerase-amplified genomic DNA fragments as template. The locus-specific primer will determine the position and direction of the genome walk. Two rounds of successive PCR amplifications by locus-specific and walker primers and their corresponding nested primers effectively amplify the flanking DNA fragments. The desired PCR fragment can be either cloned or sequenced directly using another nested, locus-specific primer. We successfully used this protocol to isolate and sequence 5′ flanking regions/promoters of selected plant genes. 相似文献
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T. Rajesh S. Maruthasalam K. Kalpana K. Poovannan K. K. Kumar E. Kokiladevi D. Sudhakar R. Samiyappan P. Balasubramanian 《Biologia Plantarum》2016,60(4):749-756
Development of transgenic plants by introducing defense genes is one of the strategies to engineer disease resistance. Transgenic ASD16 rice plants harbouring rice chitinase chi11 gene, belonging to a PR-3 group of defense gene conferring sheath blight (Rhizoctonia solani Kuhn) resistance, were used in this study. Three T2 homozygous lines (ASD16-4-1-1, 5-1-1, and 6-1-1) were identified from seven putative (T0) transgenic lines expressing chi11 using Western blotting analysis. The inheritance of sheath blight resistance in those lines was studied over generations. The stability of chi11 expression up to T4 generation in all the three homozygous lines was proved by Western blot and the stability of sheath blight resistance in the homozygous lines was proved up to T4 generation using detached leaf and intact leaf sheath assays. Among the three homozygous lines tested, ASD16-4-1-1 showed consistent results in all the generations and gave a better protection against the sheath blight pathogen than the other two lines. 相似文献
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Oindrila Raha Biswanath Sarkar Bhaskar VKS Lakkakula Veerraju Pasumarthy Sudhakar Godi Subhankar Chowdhury Pradip Raychaudhuri Raghavendra Rao Vadlamudi 《Journal of biomedical science》2013,20(1):12
Background
Several studies have demonstrated a fundamental role for the HLA in the susceptibility of, or protection to, type 1 diabetes mellitus (T1DM). However, this has not been adequately studied in Asian Indian populations. To assess the frequency of HLA class II (DPA1, DPB1, DQA1, DQB1 and DRB1) associated to susceptibility or protection toT1DM in a Bengali population of India with diabetes.Results
Single nucleotide polymorphism study. The HLA genotyping was performed by a polymerase chain reaction followed by their HLA-DP, DQ, and DRB1 genotypes and haplotypes by sequencing method. The results are studied by Plink software. The χ2 tests were used for the inferential statistics. To our knowledge, this study is the first of a kind which has attempted to check the HLA association with T1DM by SNPs analysis. The study recruited 151 patients with T1DM and same number of ethno-linguistic, sex matched non-diabetic controls. The present study found a significant SNP rs7990 of HLA-DQA1 (p = 0.009) negative correlation, again indicating that risk from HLA is considerably more with T1DM.Conclusions
This study demonstrates that the HLA class-II alleles play a major role in genetic basis of T1DM. 相似文献8.
Varsha Pathare Sudhakar Srivastava Penna Suprasanna 《Acta Physiologiae Plantarum》2013,35(12):3377-3389
This study evaluated the effects of arsenic (As) exposure on carbon, nitrogen, and sulfur (CNS) metabolism in Brassica juncea. Two contrasting, tolerant (TPM-1) and sensitive (TM-4), varieties of B. Juncea were selected and grown either in control sand (150 g) or in sand containing 10 mg of arsenate. Harvesting was performed at 7 and 15 days and various metabolites and enzymes of CNS as well as γ-aminobutyric acid (GABA) metabolism were analyzed. At 7 days, TM-4 showed significantly higher As accumulation and stressed phenotype with increase in superoxide radicals, malondialdehyde, and cell death, as compared with TPM-1. However, the level of hydrogen peroxide was higher in TPM-1 than in TM-4. The level of GABA and the activity of glutamate decarboxylase increased in both roots and shoots of TPM-1, but not in TM-4. The level of nitrate and sulfate increased and decreased in shoots of TPM-1 and TM-4, respectively. The supply of fumarate and succinate was maintained in both shoots and roots of TPM-1 while it was only in shoots of TM-4. There was significant alteration in the profile of amino acids and in sulfur and nitrogen metabolism. However, at 15 days, As accumulation of both varieties was found to be similar along with an increase in GABA, nitrate, and sulfate in both shoots and roots except sulfate in TM-4. Supply of fumarate and succinate was also maintained and other responses were found to be similar in TPM-1 and TM-4. The study demonstrates that responses of CNS metabolism differ in varietal and time-dependent manner. 相似文献
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