Archivos de biologia y medicina experimentales最新文献_第8页

Involvement of structural and nonstructural polypeptides on rotavirus RNA synthesis. 结构和非结构多肽参与轮状病毒RNA合成。

Archivos de biologia y medicina experimentales Pub Date : 1988-12-01

A M Sandino, J Pizarro, J Fernández, M C Fellay, E Spencer

{"title":"Involvement of structural and nonstructural polypeptides on rotavirus RNA synthesis.","authors":"A M Sandino, J Pizarro, J Fernández, M C Fellay, E Spencer","doi":"","DOIUrl":"","url":null,"abstract":"Rotavirus are segmented double stranded RNA viruses with a double protein capsid around a central core. The virus replicates in the cell cytoplasm. After infection, eleven mRNAs are transcribed from the viral genome. To characterize further the infection cycle, viral polypeptide synthesis and RNA replication were studied using labelled precursors. The involvement of nonstructural polypeptides NS34 and NS35 was determined by the kinetics of the appearance of viral polypeptides in infected cells. Experiments in which cycloheximide was used showed that the synthesis of both polypeptides was required to begin RNA replication. The isolation of subviral particles at 8 hours postinfection indicates that there is a particle containing the nonstructural polypeptides and the structural polypeptides VP1, VP2, and VP6 that seem to be able to transcribe the viral genome to produce other RNA species. The results suggest that there is a core-like particle similar to one obtained in vitro which upon the addition of VP6 is able to transcribe the virus genome. This seems to indicate that core-like particles may alter their specificity for plus or minus RNA synthesis depending upon the polypeptides that interact with it. The interaction between VP6 and the viral core was analyzed by means of antibodies raised against the viral core and VP6. The results suggest that VP6 contains a specific binding site to the core complex and this interaction allows the synthesis of mRNA.","PeriodicalId":75552,"journal":{"name":"Archivos de biologia y medicina experimentales","volume":"21 3-4","pages":"381-92"},"PeriodicalIF":0.0,"publicationDate":"1988-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13992850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Intracellular signaling transduction in the differentiation of Trypanosoma cruzi: role of cAMP. 克氏锥虫细胞内信号转导的分化:cAMP的作用。

Archivos de biologia y medicina experimentales Pub Date : 1988-12-01

R Rangel-Aldao, F Triana, G Comach, T Abate, V Fernández, D McMahon-Pratt

{"title":"Intracellular signaling transduction in the differentiation of Trypanosoma cruzi: role of cAMP.","authors":"R Rangel-Aldao, F Triana, G Comach, T Abate, V Fernández, D McMahon-Pratt","doi":"","DOIUrl":"","url":null,"abstract":"We have studied the cell differentiation of Trypanosoma cruzi in an vitro system that allows the transformation of epimastigotes into metacyclic trypomastigotes. Intracellular cAMP levels of epimastigotes increased 3 fold prior to their differentiation into metacyclics where cAMP remained elevated 3.7 fold with respect to epimastigotes. We also observed a 3 fold increase in the specific activity of cAMP-binding of metacyclics crude homogenates. This activity resided in a cAMP-binding receptor protein (CARPT) which was different from the typical cAMP-binding subunits (RI and RII) of cAMP-dependent protein kinases, as shown by the use of polyclonal antibodies prepared against these two types of proteins. Anti-RI antibodies did not react with CARPT, and anti-RII antibodies gave a cross reaction with CARPT which was at least 1,000 fold less sensitive than the one shown by the homologous antigen. On Western blots CARPT displayed a major band with Mr = 87,000 instead of Mr = 56,000 for RII. These studies implicate that cAMP may act as a mediator of the cell differentiation of T. cruzi by a mechanism involving a novel type of cAMP-binding receptor.","PeriodicalId":75552,"journal":{"name":"Archivos de biologia y medicina experimentales","volume":"21 3-4","pages":"403-8"},"PeriodicalIF":0.0,"publicationDate":"1988-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13992851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Sequence conservations in vertebrate homeo-box mRNAs. 脊椎动物同源盒状mrna的序列保守性。

Archivos de biologia y medicina experimentales Pub Date : 1988-12-01

E M De Robertis, T R Burglin, A Fritz, G Oliver, K Cho, C V Wright

引用次数: 0

[Sociedad Chilena de Ciencias Fisiológicas. Balneario el Retiro (Quilpue), 29-30 April 1988. 3d annual meeting. Abstracts]. 智利生理科学学会。Balneario el Retiro (Quilpue)， 1988年4月29-30日。3d年会。Abstracts]。

Archivos de biologia y medicina experimentales Pub Date : 1988-12-01

引用次数: 0

[Sección de Biología Celular, Sociedad de Biología de Chile. 2d annual meeting. 25-27 August 1988, Termas de Panimávida. Abstracts]. [智利生物学学会细胞生物学科。2d年会上。1988年8月25-27日，panimavida温泉。Abstracts]。

Archivos de biologia y medicina experimentales Pub Date : 1988-12-01

引用次数: 0

[The Chilean Society of Reproduction and Development. 2nd annual meeting. La Serena, November 22-24, 1988. Abstracts]. 智利生殖与发展协会，第二届年会。1988年11月22日至24日，拉塞雷纳。摘要]。

Archivos de biologia y medicina experimentales Pub Date : 1988-11-01

引用次数: 0

[The Society of Biology of Chile. 31st annual meeting. La Serena, November 23-26, 1988. Abstracts]. 智利生物学会。第31届年会。1988年11月23日至26日，La Serena摘要]。

Archivos de biologia y medicina experimentales Pub Date : 1988-11-01

引用次数: 0

Photoaffinity labeling of pyruvate kinase from rabbit muscle. 兔肌中丙酮酸激酶的光亲和标记。

Archivos de biologia y medicina experimentales Pub Date : 1988-06-01

S Bazaes, M Bosch, H J Schäfer, J Eyzaguirre

{"title":"Photoaffinity labeling of pyruvate kinase from rabbit muscle.","authors":"S Bazaes, M Bosch, H J Schäfer, J Eyzaguirre","doi":"","DOIUrl":"","url":null,"abstract":"Several studies have been performed on the structure of muscle pyruvate kinase. X-ray diffraction has provided a three-dimensional picture of the active site, and chemical modification studies have revealed essential amino acid residues for substrate binding or catalysis. We have shown that 8-azido-ADP (N3 ADP) behaves as a photoaffinity label for the enzyme. This reagent upon irradiation produces inactivation of the enzyme, and the activity loss is protected by nucleotides. The partially modified enzyme shows the same Km for ADP as the native one suggesting an \"all or none\" inactivation effect. The incorporation of 1 mole of 14C-N3 ADP per subunit correlates with complete inactivation. A radioactive peptide was isolated from the enzyme labeled with 14C-N3 ADP. The partial sequence of this peptide showed that it corresponds to the same peptide isolated from rabbit muscle pyruvate kinase labeled with dialdehyde-ADP and with trinitrobenzenesulfonate. This peptide is identical to a region in the cat and chicken muscle enzymes, and also a high degree of homology is found in a region of the rat liver and yeast enzymes. These studies show that N3 ADP binds to the same site as dialdehyde-ADP in rabbit muscle pyruvate kinase, and this site seems to be the nucleotide binding site.","PeriodicalId":75552,"journal":{"name":"Archivos de biologia y medicina experimentales","volume":"21 1","pages":"123-7"},"PeriodicalIF":0.0,"publicationDate":"1988-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14114349","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Proteolysis of mitochondrial-coded and nuclear-coded proteins found in yeast mitochondria. 酵母线粒体中发现的线粒体编码蛋白和核编码蛋白的蛋白质水解。

Archivos de biologia y medicina experimentales Pub Date : 1988-06-01

G Jacob, R Téllez, W Torres, R Ocasio, C Basilio, C George-Nascimento

引用次数: 0

The relationship between the structures of four beta-lactamases obtained from Bacillus cereus. 蜡样芽孢杆菌中四种β -内酰胺酶的结构关系。

Archivos de biologia y medicina experimentales Pub Date : 1988-06-01

H Cid, O Carrillo, M Bunster, J Martínez, V Vargas

引用次数: 0