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81.
Yamane J Kubo A Nakayama K Yuba-Kubo A Katsuno T Tsukita S Tsukita S 《Experimental cell research》2007,313(16):3472-3485
The small GTPase Rab6 regulates retrograde membrane traffic from endosomes to the Golgi apparatus and from the Golgi to the endoplasmic reticulum (ER). We examined the role of a Rab6-binding protein, TMF/ARA160 (TATA element modulatory factor/androgen receptor-coactivator of 160 kDa), in this process. High-resolution immunofluorescence imaging revealed that TMF signal surrounded Rab6-positive Golgi structures and immunoelectron microscopy revealed that TMF is concentrated at the budding structures localized at the tips of cisternae. The knockdown of either TMF or Rab6 by RNA interference blocked retrograde transport of endocytosed Shiga toxin from early/recycling endosomes to the trans-Golgi network, causing missorting of the toxin to late endosomes/lysosomes. However, the TMF knockdown caused Rab6-dependent displacement of N-acetylgalactosaminyltransferase-2 (GalNAc-T2), but not beta1,4-galactosyltransferase (GalT), from the Golgi. Analyses using chimeric proteins, in which the cytoplasmic regions of GalNAc-T2 and GalT were exchanged, revealed that the cytoplasmic region of GalNAc-T2 plays a crucial role in its TMF-dependent Golgi retention. These observations suggest critical roles for TMF in two Rab6-dependent retrograde transport processes: one from endosomes to the Golgi and the other from the Golgi to the ER. 相似文献
82.
Germain H Houde J Gray-Mitsumune M Sawasaki T Endo Y Rivoal J Matton DP 《FEBS letters》2007,581(26):5137-5142
Solanum chacoense ovule receptor kinase 28 (ScORK28) was found among 30 receptor kinases from an ovule cDNA library enriched for weakly expressed mRNAs. This LRR-RLK displayed high level of tissue specificity at the RNA and protein levels and was predominantly expressed in female reproductive tissues. Protein expression analyses in planta revealed that ScORK28 was N-glycosylated and ScORK28::GFP fusion analyses showed that it was localized at the plasma membrane. Bacterial expression of ScORK28 catalytic domain followed by kinase activity assays revealed that ScORK28 is an active Mg2+-dependent protein kinase and that the juxtamembrane domain is necessary for kinase activity. 相似文献
83.
根据http://www.tigr.org中与小麦几丁质酶基因相关的序列TC187877,设计引物,分别从小麦品种Gamenya和苏麦3号中扩增到大小约为1 000bp的片段。经序列测定和软件分析比较,发现这些片段所编码的蛋白质氨基酸序列,都有CHITINASE-19.1和CHITINASE-19.2的基序,为第II类几丁质酶基因。扩增的核酸序列在GenBank上发表,登录号分别为AY973229和AY973230。 相似文献
84.
Sawa T Zaki MH Okamoto T Akuta T Tokutomi Y Kim-Mitsuyama S Ihara H Kobayashi A Yamamoto M Fujii S Arimoto H Akaike T 《Nature chemical biology》2007,3(11):727-735
The signaling pathway of nitric oxide (NO) depends mainly on guanosine 3',5'-cyclic monophosphate (cGMP). Here we report the formation and chemical biology of a nitrated derivative of cGMP, 8-nitroguanosine 3',5'-cyclic monophosphate (8-nitro-cGMP), in NO-mediated signal transduction. Immunocytochemistry demonstrated marked 8-nitro-cGMP production in various cultured cells in an NO-dependent manner. This finding was confirmed by HPLC plus electrochemical detection and tandem mass spectrometry. 8-Nitro-cGMP activated cGMP-dependent protein kinase and showed unique redox-active properties independent of cGMP activity. Formation of protein Cys-cGMP adducts by 8-nitro-cGMP was identified as a new post-translational modification, which we call protein S-guanylation. 8-Nitro-cGMP seems to regulate the redox-sensor signaling protein Keap1, via S-guanylation of the highly nucleophilic cysteine sulfhydryls of Keap1. This study reveals 8-nitro-cGMP to be a second messenger of NO and sheds light on new areas of the physiology and chemical biology of signal transduction by NO. 相似文献
85.
Schmitt Franz-Josef Campbell Züleyha Yenice Bui Mai Vi Hüls Anne Tomo Tatsuya Chen Min Maksimov Eugene G. Allakhverdiev Suleyman I. Friedrich Thomas 《Photosynthesis research》2019,139(1-3):185-201
Photosynthesis Research - The phototrophic cyanobacterium Halomicronema hongdechloris shows far-red light-induced accumulation of chlorophyll (Chl) f, but the involvement of the pigment in... 相似文献
86.
Kcc4, a kinase of the budding yeast Saccharomyces cerevisiae, is homologous to the bud neck protein kinases Hsl1/Nik1 and Gin4. We report here that a GFP-Kcc4 fusion protein is localized at the bud neck and that the non-kinase domain is required for this localization. We also demonstrate that Kcc4 associates with septin proteins in vitro and in vivo by two-hybrid analysis, GST pull-down experiments, immunoprecipitation, and analysis of direct association with affinity-purified GST-Kcc4 and MBP-Septin proteins. From the results obtained here, we suggest that Cdc11 is the primary association partner of Kcc4. 相似文献
87.
Satoshi Nojima Masayuki Sakuma Ritsuo Nishida Yasumasa Kuwahara 《Journal of Insect Behavior》1999,12(5):627-640
In the courtship behavior of the German cockroach, the male presents tergal glands to the female and feeds her with glandular secretions to place her in the appropriate precopulatory position. The phagostimulant activity of the secretions was quantitatively examined using the polyethylene glycol film method. The methanol extract of the glands on the eighth tergite induced a potent feeding response in 6-day-old virgin females (EC
50
= 0.0037 male equivalent/40 g PEG spot). However, there was no temporal relation between the feeding response and the sexual receptivity of the females. Moreover, besides virgin females, the extract induced a feeding response in gravid or mated females, males, and the last-instar nymphs. These results strongly suggest that the secretions function as a dietary feeding stimulant in principle but as a courtship pheromone in the context of courtship behavior where the stimulants are offered as a nuptial gift. 相似文献
88.
Suppressor of cytokine signaling 1 (SOCS-1) and SOCS-3 cause insulin resistance through inhibition of tyrosine phosphorylation of insulin receptor substrate proteins by discrete mechanisms 总被引:24,自引:0,他引:24 下载免费PDF全文
Insulin resistance is a pathophysiological component of type 2 diabetes and obesity and also occurs in states of stress, infection, and inflammation associated with an upregulation of cytokines. Here we show that in both obesity and lipopolysaccharide (LPS)-induced endotoxemia there is an increase in suppressor of cytokine signaling (SOCS) proteins, SOCS-1 and SOCS-3, in liver, muscle, and, to a lesser extent, fat. In concordance with these increases by LPS, tyrosine phosphorylation of the insulin receptor (IR) is partially impaired and phosphorylation of the insulin receptor substrate (IRS) proteins is almost completely suppressed. Direct overexpression of SOCS-3 in liver by adenoviral-mediated gene transfer markedly decreases tyrosine phosphorylation of both IRS-1 and IRS-2, while SOCS-1 overexpression preferentially inhibits IRS-2 phosphorylation. Neither affects IR phosphorylation, although both SOCS-1 and SOCS-3 bind to the insulin receptor in vivo in an insulin-dependent fashion. Experiments with cultured cells expressing mutant insulin receptors reveal that SOCS-3 binds to Tyr960 of IR, a key residue for the recognition of IRS-1 and IRS-2, whereas SOCS-1 binds to the domain in the catalytic loop essential for IRS-2 recognition in vitro. Moreover, overexpression of either SOCS-1 or SOCS-3 attenuates insulin-induced glycogen synthesis in L6 myotubes and activation of glucose uptake in 3T3L1 adipocytes. By contrast, a reduction of SOCS-1 or SOCS-3 by antisense treatment partially restores tumor necrosis factor alpha-induced downregulation of tyrosine phosphorylation of IRS proteins in 3T3L1 adipocytes. These data indicate that SOCS-1 and SOCS-3 act as negative regulators in insulin signaling and serve as one of the missing links between insulin resistance and cytokine signaling. 相似文献
89.
Chloroplast phylogeny indicates that bryophytes are monophyletic 总被引:3,自引:0,他引:3
Nishiyama T Wolf PG Kugita M Sinclair RB Sugita M Sugiura C Wakasugi T Yamada K Yoshinaga K Yamaguchi K Ueda K Hasebe M 《Molecular biology and evolution》2004,21(10):1813-1819
Opinions on the basal relationship of land plants vary considerably and no phylogenetic tree with significant statistical support has been obtained. Here, we report phylogenetic analyses using 51 genes from the entire chloroplast genome sequences of 20 representative green plant species. The analyses, using translated amino acid sequences, indicated that extant bryophytes (mosses, liverworts, and hornworts) form a monophyletic group with high statistical confidence and that extant bryophytes are likely sisters to extant vascular plants, although the support for monophyletic vascular plants was not strong. Analyses at the nucleotide level could not resolve the basal relationship with statistical confidence. Bryophyte monophyly inferred using amino acid sequences has a good statistical foundation and is not rejected statistically by other data sets. We propose bryophyte monophyly as the currently best hypothesis. 相似文献
90.