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排序方式: 共有381条查询结果,搜索用时 27 毫秒
1.
K. K. Narayanan P. Senthilkumar V. V. Sridhar G. Thomas J. Thomas 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1995,90(7-8):1087-1093
In the fertile rice line IR 36 there are two copies of the apocytochrome b (cob) gene: a functional copy, cob 1, and a pseudogene, cob 2 (Kaleikau et al. 1992). In a survey of diverse rice lines, we found that cob 2 was absent in the wild abortive(WA)-type cytoplasmic male-sterile cytoplasm, but was present in the fertile lines. While cob 1 was conserved among all the lines, fertile and sterile, the cob 2 region was different in the fertile lines tested. The 5′ regions of most cob 2 loci were similar to cob 1 (about 4 kb of the flanking region and most of the coding region), but the 3′ region varied among different fertile lines. The point of divergence, the break-point, from the cob 1 sequence was conserved in all the cob 2 regions tested. In all the cob 2 regions, this break-point seems to be linked to the variable region of cob 2 through a conserved 192-bp segment, which is not a part of cob 1. It is proposed that the cob 2 regions could have been produced by recombination or insertion events involving cob 1 and the 192-bp segment which is present at different locations in the mitochondrial genomes of the various rice lines. 相似文献
2.
N Muthusamy A R Baluyut B Subbarao 《Journal of immunology (Baltimore, Md. : 1950)》1991,147(8):2483-2492
The differential effect of cAMP on the regulation of early biochemical and cellular functions mediated through two different receptors on murine B cells are reported here. Surface IgM, the Ag receptor, and Lyb2, a 45-kDa differentiation Ag are concomitantly expressed on mature murine B lymphocytes. Triggering of B cells through these molecules, independently, resulted in inositol 1,4,5-triphosphate (IP3) generation, increase in intracellular Ca2+ levels, and cell enlargement associated with progression of cells from G0 to G1 ultimately resulting in DNA synthesis. Pretreatment of resting B cells with cholera toxin as well as other agents that raise the intracellular cAMP [(cAMP)i] such as forskolin, N6,2'-O-dibutyryl cyclic AMP, and 3-isobutyl-1 methyl xanthine inhibited the Ag receptor but not Lyb2-mediated DNA synthesis. The elevation of (cAMP)i inhibited the surface IgM but not Lyb2-mediated IP3 generation, Ca2+ response, and progression from G0 to G1 phase of the cell cycle. Failure of forskolin or N6,2'-O-dibutyryl cyclic AMP to inhibit Lyb2-mediated responses did not appear to be due to induction of cAMP-specific phosphodiesterase activity. Concentrations of H8 [N-(2-(methylamino)-ethyl)-5-isoquinoline sulfonamide, diHCl] inhibitory to cAMP dependent PKA prevented the inhibitory effect of forskolin on surface IgM-mediated Ca2+ response, suggesting that cAMP exerted its effects through PKA. These findings suggest that distinct PLC-coupled receptors, such as sIgM and Lyb2 molecules in B cells, may use either alternative mechanisms for phosphatidylinositol 4,5-bisphosphate hydrolysis or may use different intermediary transducer molecules that differ in their sensitivity to increased (cAMP)i levels. Thus "cross-talk" among cAMP and phosphatidylinositol signaling pathways was demonstrated for IgM but not Lyb2-mediated B cell activation. 相似文献
3.
Karuppanan Muthusamy Kathir Li Gao Dakshinamurthy Rajalingam Sherri Brixey Dan Davis Igor Prudovsky 《生物化学与生物物理学报:生物膜》2010,1798(2):297-302
Human fibroblast growth factor (hFGF-1) is a ∼ 17 kDa heparin binding cytokine. It lacks the conventional hydrophobic N-terminal signal sequence and is secreted through non-classical secretion routes. Under stress, hFGF-1 is released as a multiprotein complex consisting of hFGF-1, S100A13 (a calcium binding protein), and p40 synaptotagmin (Syt1). Copper (Cu2+) is shown to be required for the formation of the multiprotein hFGF-1 release complex (Landriscina et al. ,2001; Di Serio et al., 2008). Syt1, containing the lipid binding C2B domain, is believed to play an important role in the eventual export of the hFGF-1 across the lipid bilayer. In this study, we characterize Cu2+ and lipid interactions of the C2B domain of Syt1 using multidimensional NMR spectroscopy. The results highlight how Cu2+ appears to stabilize the protein bound to pS vesicles. Cu2+ and lipid binding interface mapped using 2D 1H-15N heteronuclear single quantum coherence experiments reveal that residues in β-strand I contributes to the unique Cu2+ binding site in the C2B domain. In the absence of metal ions, residues located in Loop II and β-strand IV contribute to binding to unilamelar pS vesicles. In the presence of Cu2+, additional residues located in Loops I and III appear to stabilize the protein-lipid interactions. The results of this study provide valuable information towards understanding the molecular mechanism of the Cu2+-induced non-classical secretion of hFGF-1. 相似文献
4.
Hematophagous activity of Mecistocirrus digitatus, which causes substantial blood and weight loss in large ruminants, is an emerging challenge due to the economic loss it brings to the livestock industry. Infected animals are treated with anthelmintic drugs, based on the identification of helminth species and the severity of infection; however, traditional methods such as microscopic identification and the counting of eggs for diagnosis and determination of level of infection are laborious, cumbersome and unreliable. To facilitate the detection of this parasite, a SYBR green-based real-time PCR was standardized and validated for the detection of M. digitatus infection in cattle and buffaloes. Oligonucleotides were designed to amplify partial Internal Transcribed Spacer (ITS)-1 sequence of M. digitatus. The specificity of the primers was confirmed by non-amplification of DNA extracted from other commonly occurring gastrointestinal nematodes in ruminants. Plasmids were ligated with partial ITS-1 sequence of M. digitatus, serially diluted (hundred fold) and used as standards in the real-time PCR assay. The quantification cycle (Cq) values were plotted against the standard DNA concentration to produce a standard curve. The assay was sensitive enough to detect one plasmid containing the M. digitatus DNA. Clinical application of this assay was validated by testing the DNA extracted from the faeces of naturally infected cattle (n = 40) and buffaloes (n = 25). The results were compared with our standard curve to calculate the quantity of M. digitatus in each faecal sample. The Cq value of the assay depicted a strong linear relationship with faecal DNA content, with a regression coefficient of 0.984 and efficiency of 99%. This assay has noteworthy advantages over the conventional methods of diagnosis because it is more specific, sensitive and reliable. 相似文献
5.
Senthilkumar Nangan Aziz Md. Abdul Pannipara Mehboobali Alphonsa A. Therasa Al-Sehemi Abdullah G. Balasubramani A. Gnana kumar G. 《Bioprocess and biosystems engineering》2020,43(1):97-109
Bioprocess and Biosystems Engineering - Despite the green energy generation with low cost compared to conventional fuel cells, microbial fuel cells (MFCs) still suffer with anode related... 相似文献
6.
De Bauw Pieterjan Smolders Erik Verbeeck Mieke Senthilkumar Kalimuthu Houben Eva Vandamme Elke 《Plant and Soil》2021,463(1-2):187-204
Plant and Soil - Upland rice production is often constrained by phosphorus deficiency (P) and drought events. Methods are needed to maximize P use efficiency, while promoting deep root development... 相似文献
7.
Baveja Aanchal Chhabra Rashmi Panda Kusuma K. Muthusamy Vignesh Zunjare Rajkumar U. Hossain Firoz 《Journal of plant biochemistry and biotechnology.》2021,30(2):265-274
Journal of Plant Biochemistry and Biotechnology - Sweet corn has emerged as a popular vegetable worldwide. Commercial shrunken2 (sh2)-based sweet corn lacks lysine, tryptophan and provitamin-A,... 相似文献
8.
BS Sabna Thankappan Bency Mahendran Ramasamy Muthusamy Gayathri Femil selta Daniel Raja Angayarkanni Jayaraman 《Probiotics and antimicrobial proteins》2021,13(4):993-1004
Probiotics and Antimicrobial Proteins - Gamma-aminobutyric acid (GABA) is a principal inhibitory neurotransmitter in the central nervous system and is produced by irreversible decarboxylation of... 相似文献
9.
Kumari Anjali Ameri Shijin Marraiki Najat Elgorban Abdallah M. Aroulmoji Vincent Ponnuchamy Kumar Govarthanan Muthusamy Selvankumar Thangaswamy 《International journal of peptide research and therapeutics》2021,27(1):385-395
International Journal of Peptide Research and Therapeutics - The conopeptides are the conotoxin of Conus loroisii have wide applications in drug development. This work emphasizes the isolation and... 相似文献
10.
K.N. Sunil Kumar K.G. Divya M. Senthilkumar S.G. Sreelekshmi Hady M. El-Sheikh Mohamed A. El-Sheikh Abdullah Al-Ghamdi Bander Al-Munqedhi 《Saudi Journal of Biological Sciences》2021,28(2):1239-1245
Loranthaceae family includes hemiparasitic members which are seen invading a wide range of commercial crops. Helicanthes elasticus (Desv.) Danser is very common on mango trees. Though parasitic in nature, this mistletoe is also medicinally important as fetoprotective, against vesicular calculi and kidney infections. This study is an attempt to document macro-microscopical features of parasitic root, fruit and host-mistletoe tissue interaction in the haustorium of H. elasticus growing on mango stems. Collection, preservation, sectioning, staining and photomicrography of the root, fruit and host-mistletoe union were done as per standard methodologies of anatomical studies. Though there is resemblance to the normal roots in morphology as well as anatomy, the microscopic finding of large number of branched stone cells in the roots is interesting. The morpho-anatomical features recorded would help in understanding the infection biology of this mistletoe. The eradication during the earlier stages of its establishment from seed or from the root creeping over the surface of the host can help in controlling this parasite infection on commercially important host plants. 相似文献