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901.
902.
Kamaluddin Rishi Muni Singh Malik Zainul Abdin Mather Ali Khan Tanweer Alam Salim Khan Lal Chand Prasad Arun Kumar Joshi 《Journal of Plant Biology》2007,50(4):504-507
To understand the genetic control of grain filling duration (GFD), i.e., the number of days from anthesis to physiological
maturity, we studied the F1, F2, BC1 and BC2 generations of six spring wheat crosses from nine varieties/genotypes. Generation mean analysis for gene effects indicated
that one or more types of epistasis were significant in all crosses. In each pairing, the F1 and F2 means were either intermediate or closer to the mean of the parent having the longer GFD. Our narrow-sense heritability estimate
was reasonably high, at 47.67 (based on diallel analysis). This demonstrated that progress could be made from the selection
in these crosses for either long or short GFD. The two early varieties that had identical maturity durations differed in their
GFD values, indicating that maturity dates are not good criteria when choosing parents for modifying GFD. To utilize favorable
additive × additive effects during this selection, we suggest that a single seed descent (SSD) or bulk popula-tion approach
be adopted. In comparison, dominance effects would prove quite useful in hybrid wheat breeding programs. 相似文献
903.
Prasad AK Singh SK Kalra N Singhal N Wengel J Parmar VS 《Nucleosides, nucleotides & nucleic acids》2007,26(10-12):1517-1521
Immobilized Candida antarctica lipase and Thermomyces lanuginosus lipase catalyze the deacylation of precursors of LNA analogs, 4'-C-acyloxymethyl-2',3',5'-tri-O-acyl-beta-L-threo-pentofuranosylthymine and 4-C-acyloxymethyl-3,5-di-O-acyl-1,2-O-(1-methylethylidene)-beta-L-threo-pentofuranose, respectively in a highly selective and efficient manner. 相似文献
904.
A T-DNA based promoter trapped mutant has led to the identification of a novel lateral organ junction specific promoter upstream of the pentatricopeptide repeat (PPR) protein coding gene LOJ in Arabidopsis thaliana by our laboratory. Various in silico based prediction tools are employed to characterize the upstream sequence of the LOJ gene. Out of numerous cis-elements detected in the LOJ promoter a few are considered important based on the expression pattern of the LOJ gene. These elements would provide a basis for designing experiments for more accurate promoter function annotation. A comparative search for conserved elements in the 5'-upstream region of a few genes involved in lateral organ development and meristem related expression reveals a few common relevant regulatory motifs. The coding region of the LOJ gene is intron-less and contains 19 PPR units. Based on in silico analysis, LOJ protein is predicted to be hydrophobic in nature and targeted to mitochondria. A partial 3D model of LOJ protein has been suggested using a homology-based modeling program. 相似文献
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Masaoka A Gassman NR Kedar PS Prasad R Hou EW Horton JK Bustin M Wilson SH 《The Journal of biological chemistry》2012,287(33):27648-27658
In mammalian cells, the nucleosome-binding protein HMGN1 (high mobility group N1) affects the structure and function of chromatin and plays a role in repair of damaged DNA. HMGN1 affects the interaction of DNA repair factors with chromatin and their access to damaged DNA; however, not all of the repair factors affected have been identified. Here, we report that HMGN1 affects the self-poly(ADP-ribosyl)ation (i.e., PARylation) of poly(ADP-ribose) polymerase-1 (PARP-1), a multifunctional and abundant nuclear enzyme known to recognize DNA lesions and promote chromatin remodeling, DNA repair, and other nucleic acid transactions. The catalytic activity of PARP-1 is activated by DNA with a strand break, and this results in self-PARylation and PARylation of other chromatin proteins. Using cells obtained from Hmgn1(-/-) and Hmgn1(+/+) littermate mice, we find that in untreated cells, loss of HMGN1 protein reduces PARP-1 self-PARylation. A similar result was obtained after MMS treatment of these cells. In imaging experiments after low energy laser-induced DNA damage, less PARylation at lesion sites was observed in Hmgn1(-/-) than in Hmgn1(+/+) cells. The HMGN1 regulation of PARP-1 activity could be mediated by direct protein-protein interaction as HMGN1 and PARP-1 were found to interact in binding assays. Purified HMGN1 was able to stimulate self-PARylation of purified PARP-1, and in experiments with cell extracts, self-PARylation was greater in Hmgn1(+/+) than in Hmgn1(-/-) extract. The results suggest a regulatory role for HMGN1 in PARP-1 activation. 相似文献
910.
Kim J Wang L Li Y Becnel KD Frey KM Garforth SJ Prasad VR Schinazi RF Liotta DC Anderson KS 《Bioorganic & medicinal chemistry letters》2012,22(12):4064-4067
Pre-steady state kinetic analysis was utilized for biochemical evaluation of a series of cyclobutyl adenosine nucleotide analogs with HIV-1 RT(WT). The phosphonyl-diphosphate form of the cyclobutyl nucleotide, 5, was the most efficiently incorporated of the series. Nucleotide 5 was fourfold more efficiently incorporated than the FDA approved TFV-DP by RT(WT). The kinetics of incorporation for 5 using the drug resistant mutant enzyme K65R was also determined. Compound 5 was threefold more efficiently incorporated compared to TFV-DP with RT(K65R). These results demonstrate cyclobutyl adenosine analogs can act as substrates for incorporation by HIV-1 RT and be a potential scaffold for HIV inhibitors. 相似文献