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Various adenine nucleotides activated phospholipase C of FRTL-5 cell membranes in the following order of activity, ATP gamma S greater than ATP greater than AppNp greater than AppCp = ADP greater than MeSATP. This order was well consistent with that observed in intact cells. Such activation occurred only in the presence of appropriate concentrations of GTP gamma S and Ca2+, in a way similar to the norepinephrine-induced activation. NaF, a non-specific GTP-binding protein (G-protein) activator, also stimulated the enzyme. These adenine nucleotides, norepinephrine and NaF-induced activations were inhibited by GDP beta S. We conclude that a G-protein is involved in the adenine nucleotides-induced activation of phospholipase C via P2-purinergic receptor in FRTL-5 cells. 相似文献
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Takimoto Yuki Monkawa Akira Nagata Kohki Kobayashi Masahiro Kinoshita Mariko Gessei Tomoko Mori Toshiya Kagi Hiroyuki 《Plasmonics (Norwell, Mass.)》2020,15(3):805-811
Plasmonics - Detection and monitoring of SO2 is important because it is a representative toxic gas in the atmospheric environment that is emitted from industrial and natural processes. Localized... 相似文献
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Yizhi Jiang Dongping Huang Yuji Kondo Miao Jiang Zhenni Ma Lu Zhou Jian Su Xia Bai Changgeng Ruan Zhaoyue Wang Lijun Xia 《Journal of cellular and molecular medicine》2020,24(7):4356-4361
Hereditary thrombotic thrombocytopenic purpura (TTP) is an autosomal recessive thrombosis disorder, caused by loss-of-function mutations in ADAMTS13. Mutations in the CUB domains of ADAMTS13 are rare, and the exact mechanisms through which these mutations result in the development of TTP have not yet been fully elucidated. In this study, we identified two novel mutations in the CUB domains in a TTP family with an acceptor splice-site mutation (c.3569−1, G>A, intron 25) and a point missense mutation (c.3923, G>A, exon 28), resulting in a glycine to aspartic acid substitution (p.G1308D). In vitro splicing analysis revealed that the intronic mutation resulted in abnormal pre-mRNA splicing, and an in vitro expression assay revealed that the missense mutation significantly impaired ADAMTS13 secretion. Although both the patient and her brother displayed significantly reduced ADAMTS13 activity and increased levels of ultra-large VWF (ULVWF) multimers in plasma, only the female developed acute episodes of TTP. Our findings indicate the importance of the CUB domains for the protein stability and extracellular secretion of ADAMTS13. 相似文献
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Journal of Microbiology - The widespread use of the organochlorine insecticide lindane in the world has caused serious environmental problems. The main purpose of this paper is to investigate the... 相似文献
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Catechinopyranocyanidins A and B (cpcA and cpcB) are two purple pigments present in the seed-coat of red adzuki bean, Vigna angularis, of which cpcA is the major pigment, containing two chiral carbons in the catechin part. Their absolute configurations were determined by comparison of their experimental and quantum chemical calculated electronic circular dichroisms (ECDs). These purple pigments are labile on light irradiation and easily decompose to photo-degraded catechinopyranocyanidins A and B (pdcpcA and pdcpcB), while retaining the stereostructure of the catechin residue. We applied modified Mosher's method for determining the chirality of the secondary alcohol in pdcpcA. Hexamethylation of pdcpcA by diazomethane followed by esterification using (S)- and (R)-MTPACl gave (R)- and (S)-MTPA esters, respectively. By analysis of the NMR spectra of (R)- and (S)-MTPA esters of tetramethylated (+)-catechin, the chirality of pdcpcA was determined to be 2R, 3S, same as the absolute configuration of cpcA. 相似文献
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Maki Ohtani Jun-ichi Hikima Tae-Sung Jung Hidehiro Kondo Ikuo Hirono Haruko Takeyama Takashi Aoki 《Fish & shellfish immunology》2013,34(2):724-728
Phage display libraries are used to screen for nucleotide sequences that encode immunoglobulin variable (V) regions that are specific for a target antigen. We previously constructed an immunoglobulin new antigen receptor (IgNAR) phage display library. Here we used this library to obtain an IgNAR V region that is specific for viral hemorrhagic septicemia virus (VHSV). A phage clone (clone 653) was found to be specific for VHSV by the biopanning method. The V region of clone 653 was used to construct a 6 × His tagged recombinant IgNAR-653 V protein (rIgNAR-653) using the Escherichia coli pET system. The rIgNAR-653 protein bound specifically to VHSV, confirming its activity. 相似文献