Archivos de biologia y medicina experimentales最新文献_第7页

[19th annual meeting of the Sociedad de Genética de Chile. Santiago, Chile, 2-3 October 1986. Abstracts]. [智利生殖器官学会第19届年会]。智利圣地亚哥，1986年10月2日至3日。摘要]。

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

引用次数: 0

Remodeling of chromatin during male pronucleus formation in the sea urchin Tetrapygus niger. 黑尾海胆雄性原核形成过程中染色质的重塑。

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

M Imschenetzky, M Puchi, R Massone, A M Oyarce, M Rocco

{"title":"Remodeling of chromatin during male pronucleus formation in the sea urchin Tetrapygus niger.","authors":"M Imschenetzky, M Puchi, R Massone, A M Oyarce, M Rocco","doi":"","DOIUrl":"","url":null,"abstract":"After fertilization the cone shaped sperm nucleus is transformed into a spheroidal male pronucleus which fuses with the female pronucleus reestablishing the diploid genome. These morphological changes are correlated with biochemical transitions of sperm-specific chromosomal proteins. To obtain information on the rearrangements of chromosomal proteins after fertilization, we have followed sperm-specific nonhistones (Sp NHCP) and the sperm-specific histones (SpH) in zygotes harvested at different times post-insemination (p.i.). The acquisition of proteins synthesized de novo was determined during the time of male pronucleus formation, estimated to occur until 30 min p.i. The results obtained may be summarized as follows: 1. The fate of Sp NHCP, followed by Western blot analysis with polyclonal antibodies obtained in rabbits against the whole complement of Sp NHCP, indicates that the majority of Sp NHCP are lost shortly p.i., except two proteins of 58 Kd and 61 Kd that were not distinguishable from eggs NHCP because a crossreaction was obtained. Acidic proteins synthesized de novo were bound to chromatin between 3 and 30 min p.i., and the majority of these proteins comigrated with egg NHCP in SDS/PAGE. 2. The histones from sperm differ from their counterparts found in unfertilized eggs, both in their amino acid composition and their microheterogeneity in bidimensional gels. Sperm contain the five major SpH whereas eggs have seven major histone variants, distinct from each other, with an electrophoretic behaviour consistent with histones but a different amino acid composition. The total complement of histone variants found in zygotes collected at amphimixis is identical with that found in unfertilized eggs, suggesting that SpH should be lost before that time.(ABSTRACT TRUNCATED AT 250 WORDS)","PeriodicalId":75552,"journal":{"name":"Archivos de biologia y medicina experimentales","volume":"21 3-4","pages":"409-16"},"PeriodicalIF":0.0,"publicationDate":"1988-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14386138","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

Growth control in mouse Y-1 adrenocortical tumor cells: role of c-Ki-ras amplification and effects of ACTH. 小鼠Y-1肾上腺皮质肿瘤细胞的生长控制:c-Ki-ras扩增的作用和ACTH的影响。

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

E Kimura, H A Armelin

引用次数: 0

Expression of size-selected messenger RNA encoding the brain and adrenal gland angiotensin-II receptor in Xenopus laevis oocytes. 编码脑和肾上腺血管紧张素ii受体的大小选择信使RNA在非洲爪蟾卵母细胞中的表达。

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

N C Inestrosa, D Cross

引用次数: 0

[Sociedad de Farmacológia de Chile. 10th annual meeting. 5-6 August 1988, La Dehesa, Santiago. Abstracts]. [智利社会协会Farmacológia .第十届年会]。1988年8月5日至6日，圣地亚哥La Dehesa。摘要]。

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

引用次数: 0

[21st annual meeting of Sociedad de Genética de Chile. 25-27 August 1988, Chillán, Chile. Abstracts]. [智利生殖健康协会第二十一次年会，1988年8月25日至27日，Chillán，智利。摘要]。

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

引用次数: 0

The role of 16S RNA in ribosome function: single base alterations and their effect on in vitro protein synthesis. 16S RNA在核糖体功能中的作用:单碱基改变及其对体外蛋白质合成的影响。

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

P R Cunningham, D Negre, C Weitzmann, R Denman, K Nurse, J Ofengand

{"title":"The role of 16S RNA in ribosome function: single base alterations and their effect on in vitro protein synthesis.","authors":"P R Cunningham, D Negre, C Weitzmann, R Denman, K Nurse, J Ofengand","doi":"","DOIUrl":"","url":null,"abstract":"An in vitro system developed for the site-specific mutagenesis of 16S RNA of Escherichia coli ribosomes (Krzyzosiak et al., Biochemistry 26, 2353-2364, 1987) was used to make 10 single base changes around C1400, the residue known to be at the decoding site. C1400 was replaced by U, A, or G, 5 single base deletions at and to either side of C1400 were made, and C or U was inserted next to C1400. Another mutant possessed 7 additional nucleotides at the 3' end of the 16S RNA such that a stem and loop involving the anti-Shine-Dalgarno sequence could form. Another series of 8 mutants tested hypothetical base-pairing between C1404, G1405 and C1496, G1497. The activity of these 19 mutants in A and P site binding, and in initiation-dependent and initiation-independent peptide synthesis was determined. None of the base substitutions of C1400 were strongly inhibitory. The insertions and deletions completely blocked initiation-dependent peptide synthesis but markedly stimulated the initiation-independent reaction. The effects of tRNA binding were variable. The only alteration to block all ribosomal function was the deletion of G1401. The extra stem and loop at the 3'-end blocked initiation-dependent peptide synthesis, but all other assays were normal. The mutants which break and reform the hypothetical base-pairs had a functional pattern that suggest the contiguous base-pairs do exist and are functionally important.","PeriodicalId":75552,"journal":{"name":"Archivos de biologia y medicina experimentales","volume":"21 3-4","pages":"393-401"},"PeriodicalIF":0.0,"publicationDate":"1988-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13620673","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

International symposium: Interactions of informational macromolecules. Santiago, 14-16 January 1988. Proceedings. 国际研讨会:信息大分子的相互作用。圣地亚哥，1988年1月14日至16日。程序。

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

引用次数: 0

Generation of myc/fos transfectant Balb-3T3 cell lines. myc/fos转染Balb-3T3细胞系的产生。

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

M C Armelin, C A Joazeiro, K M Rocha, H A Armelin

引用次数: 0

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