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251.
Membrane guanylate cyclase is a cell-surface receptor with homology to protein kinases 总被引:15,自引:0,他引:15
S Singh D G Lowe D S Thorpe H Rodriguez W J Kuang L J Dangott M Chinkers D V Goeddel D L Garbers 《Nature》1988,334(6184):708-712
Guanylate cyclase has been strongly implicated as a cell-surface receptor on spermatozoa for a chemotactic peptide, and on various other cells as a receptor for atrial natriuretic peptides. Resact (Cys-Val-Thr-Gly-Ala-Pro-Gly-Cys-Val-Gly-Gly-Gly-Arg-Leu-NH2), the chemotactic peptide released by sea urchin Arbacia punctulata eggs, is specifically crosslinked to A. punctulata spermatozoan guanylate cyclase. After the binding of the peptide the state of guanylate cyclase phosphorylation modulates enzyme activity. We report here that the deduced amino-acid sequence of the spermatozoan membrane form of guanylate cyclase predicts an intrinsic membrane protein of 986 amino acids with an amino-terminal signal sequence. A single transmembrane domain separates the protein into putative extracellular and cytoplasmic-catalytic domains. The cytoplasmic carboxyl-terminal 95 amino acids contain 20% serine, the likely regulatory sites for phosphorylation. Unexpectedly, the enzyme is homologous to the protein kinase family. 相似文献
252.
Summary Ovarian hormones namely-estradiol and progesterone were observed to stimulate the activity of adenyl cyclase of the mammary gland from pregnant rabbit in vitro, unlike the lactating tissue where it was inhibited. On the other hand, non-ovarian hormones like hydrocortisone, prolactin and insulin did not have a similar effect on this enzyme.Acknowledgement. We are indebted to Dr D. Sundaresan, for his kind encouragement in this study. 相似文献
253.
P. S. Kalsi B. R. Chhabra O. S. Singh 《Cellular and molecular life sciences : CMLS》1979,35(4):481-482
Summary ,-unsaturated terpenoid ketones have a root-inducing property on the hypocotyl cuttings ofPhaseoulus aureus. Significantly isopathcoulenone, (I) is distinctly more active in causeing rooting over IAA.Acknowledgment. The work was financially supported by the Punjab State Government, India, under the scheme Chemistry of some natural products and their significance in agriculture. The authors thank Dragoco, Holzminden, Federal Republic of Germany, for supplying the samples of monoterpenes. 相似文献
254.
Heterochromatin protein 1 modifies mammalian PEV in a dose- and chromosomal-context-dependent manner 总被引:11,自引:0,他引:11
Festenstein R Sharghi-Namini S Fox M Roderick K Tolaini M Norton T Saveliev A Kioussis D Singh P 《Nature genetics》1999,23(4):457-461
Locus control regions (LCRs) are gene regulatory elements in mammals that can overcome the highly repressive effects normally associated with heterochromatic transgene locations (for example the centromere) in mice. Deletion of essential LCR sequences renders the cognate gene susceptible to this form of repression, so a proportion of the cells from transgenic mice that would normally express the transgene are silenced-a phenomenon known as position effect variegation (PEV). We show here that PEV can also occur when the transgene is non-centromeric and that the extent of variegation can be developmentally regulated. Furthermore, by overexpressing a mammalian homologue (M31) of Drosophila melanogaster heterochromatin protein 1 (HP1; refs 7,8) in transgenic mouse lines that exhibit PEV, it is possible to modify the proportion of cells that silence the transgene in a dose-dependent manner. Thus, we show M31 overexpression to have two contrasting effects which are dependent on chromosomal context: (i) it enhanced PEV in those lines with centromeric or pericentromeric transgene locations; and (ii) it suppressed PEV when the transgene was non-centromeric. Our results indicate that components or modifiers of heterochromatin may have a chromosomal-context-dependent role in gene silencing and activation decisions in mammals. 相似文献
255.
256.
The value of data 总被引:1,自引:0,他引:1
Mons B van Haagen H Chichester C Hoen PB den Dunnen JT van Ommen G van Mulligen E Singh B Hooft R Roos M Hammond J Kiesel B Giardine B Velterop J Groth P Schultes E 《Nature genetics》2011,43(4):281-283
Data citation and the derivation of semantic constructs directly from datasets have now both found their place in scientific communication. The social challenge facing us is to maintain the value of traditional narrative publications and their relationship to the datasets they report upon while at the same time developing appropriate metrics for citation of data and data constructs. 相似文献
257.
Ca2+ influx evoked across the plasma membrane upon internal store depletion is essential for a myriad of cellular functions including
gene expression, cell proliferation, differentiation and even apoptosis. Darier’s disease (DD), an autosomal dominant inherited
disorder of the skin, arising due to mutations in the isoform 2 of the sarco (endo) plasmic reticulum Ca2+ ATPase (SERCA2), exemplifies an anomaly of Ca2+ signaling disturbances. Owing to loss of function mutations in SERCA2, keratinocytes in DD patients have a reduced pool of
endoplasmic reticulum (ER) Ca2+. Importantly, the status of ER Ca2+ is critical for the activation of a class of plasma membrane Ca2+ channels referred to as store operated Ca2+ channels (SOCs). The widely expressed transient receptor potential (TRP) family of channels is proposed to be SOCs. In this
review we discuss DD from the viewpoint of Ca2+ signaling and present a potential role for TRPC1 in the disease pathogenesis.
Received 30 August 2007; received after revision 17 October 2007; accepted 6 November 2007 相似文献
258.
259.
Sudhir Kumar Singh Himanshu Pandey Jawdat Al-Bassam Larisa Gheber 《Cellular and molecular life sciences : CMLS》2018,75(10):1757-1771
Mitotic kinesin-5 bipolar motor proteins perform essential functions in mitotic spindle dynamics by crosslinking and sliding antiparallel microtubules (MTs) apart within the mitotic spindle. Two recent studies have indicated that single molecules of Cin8, the Saccharomyces cerevisiae kinesin-5 homolog, are minus end-directed when moving on single MTs, yet switch directionality under certain experimental conditions (Gerson-Gurwitz et al., EMBO J 30:4942–4954, 2011; Roostalu et al., Science 332:94–99, 2011). This finding was unexpected since the Cin8 catalytic motor domain is located at the N-terminus of the protein, and such kinesins have been previously thought to be exclusively plus end-directed. In addition, the essential intracellular functions of kinesin-5 motors in separating spindle poles during mitosis can only be accomplished by plus end-directed motility during antiparallel sliding of the spindle MTs. Thus, the mechanism and possible physiological role of the minus end-directed motility of kinesin-5 motors remain unclear. Experimental and theoretical studies from several laboratories in recent years have identified additional kinesin-5 motors that are bidirectional, revealed structural determinants that regulate directionality, examined the possible mechanisms involved and have proposed physiological roles for the minus end-directed motility of kinesin-5 motors. Here, we summarize our current understanding of the remarkable ability of certain kinesin-5 motors to switch directionality when moving along MTs. 相似文献
260.
Circular chromosome conformation capture (4C) uncovers extensive networks of epigenetically regulated intra- and interchromosomal interactions 总被引:1,自引:0,他引:1
Zhao Z Tavoosidana G Sjölinder M Göndör A Mariano P Wang S Kanduri C Lezcano M Sandhu KS Singh U Pant V Tiwari V Kurukuti S Ohlsson R 《Nature genetics》2006,38(11):1341-1347