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91.
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
92.
MpkA-Dependent and -independent cell wall integrity signaling in Aspergillus nidulans 总被引:1,自引:0,他引:1
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Fujioka T Mizutani O Furukawa K Sato N Yoshimi A Yamagata Y Nakajima T Abe K 《Eukaryotic cell》2007,6(8):1497-1510
93.
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
94.
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
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96.
Telomerase activity is known to be implicated both in cell immortalization and carcinogenesis. Telomerase activity has not been detected in most human somatic tissues. However, we previously confirmed that the activity is present both in methylazoxymethanol acetate-induced rat colonic adenocarcinoma and non-treated colonic mucosa, presumably indicating the tissue-specific activity of the enzyme in rats. To determine the standard activity of rat telomerase in various organs in relation to differences in sex, age and strain, we examined the activity by using the telomeric repeat amplification protocol (TRAP) assay. The testis, liver, and colon mucosa showed the activity. The brain had very low or negative activity in 5-week-old male rats of the F344, SD, Wistar, Donryu or ACI strains. Age (5-week-old and 9-month-old) or sex difference for the activity was not apparent in rats of these strains. In general, telomerase activity in the fetal brain, liver and kidney was stronger than in the adult organ. The telomerase activity of each organ was different from that of human. This difference may indicate that the rat has a specific mechanism for maintaining the telomeric repeats of the chromosome even in somatic tissues. The basic information resulting from this study may be useful for the study of the role of telomerase in tumorigenesis in animal experiment models. 相似文献
97.
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
98.
99.
Chondrosarcoma of the urinary bladder and establishment of a human chondrosarcoma cell line (OCUU-6)
Chondrosarcoma is a very rare tumor of the urinary bladder, with only 4 cases reported to date. In this study, we report on a case of a 73-year-old male who presented bladder mass and right hydroureteronephrosis. Radical cystectomy, right nephrectomy and left ureterocutaneoustomy were performed, and histological study disclosed chondrosarcoma of the urinary bladder. As reported in other cases, the tumor was highly aggressive with a short clinical course, and the patient died of carcinomatous pleuritis at one month after surgery. Subsequently, we successfully established a human chondrosarcoma cell line (OCUU-6) from the pleural effusion of the patient. 相似文献
100.
Yurimoto H Yamane M Kikuchi Y Matsui H Kato N Sakai Y 《Bioscience, biotechnology, and biochemistry》2004,68(10):2058-2069
Transglutaminase (TGase) from the actinomycete Streptomyces mobaraensis is a useful enzyme in the food industry, and development of an efficient production system for it would be desirable. Herein we report secretion of TGase in an enzymatically active form by methylotrophic yeasts as expression hosts. Secretory production of active TGase required a pro-peptide from TGase. When an artificial Kex2-endopeptidase recognition site was placed between the pro-peptide and mature TGase, secretion and in vitro maturation of TGase depended on Kex2-dependent cleavage. Unexpectedly, coexpression of unlinked pro-peptide with mature TGase yielded efficient secretion of the active enzyme. These results indicate that the pro-peptide from TGase functions not only in an intramolecular but also in an intermolecular manner. Site-directed mutagenesis of putative N-glycosylation sites increased the productivity of the active TGase further. A recombinant Candida boidinii strain was found to secrete active TGase up to 1.83 U/ml (about 90 mg/l) after 119 h of cultivation. 相似文献