Studies on early proteins and transformation proteins of human adenoviruses.
Studies on early proteins and transformation proteins of human adenoviruses.
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人类腺病毒早期蛋白和转化蛋白的研究。
DOI:
10.1101/sqb.1980.044.01.049
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发表时间:
1980
期刊:
影响因子:
--
通讯作者:
Cartas,MA
中科院分区:
文献类型:
--
作者:
Green,M;Wold,WS;Brackmann,K;Cartas,MA
The early genes of adenovirus 2 (Ad2) are transcribed before initiation of viral DNA synthesis at 6-7 hours postinfection (Green et al. 1971). The early genes are distributed in four noncontiguous gene regions, designated El-E4 (Flint et al. 1975, 1976; Flint and Sharp 1976; Biittner et al. 1976; Craig and Raskas 1976; Chow et al. 1977; Evans et al. 1977; Berk and Sharp 1978a).(See Fig. 1 for a diagram of the physical and genetic organization of the Ad2 genome.) Blocks E1 and E3 are located within approximate map units 1.5-11 and 76-86, respectively, and are transcribed in the rightward direction. E2 and E4 are located within approximate map units 62--68 and 92-98, respectively, and are transcribed in the leftward direction. E1 of Ad2 (and closely related Ad5) is a model important to the understanding of eukaryotic gene expression and viral cell transformation. At least two areas in El, 1.5-4.5 and 4.5-11 map units, code for two or more overlapping spliced mRNAs (Kitchingman et al. 1977; Berk and Sharp 1978a; Spector et al. 1978; LT Chow et al., pers. comm.). Because E1 is probably transcribed mainly by cell mechanisms, mapping the genes in E1 and analysis of their mRNA and polypeptide products may provide insights into the organization and expression of cellular genes. E1 is of further interest because it contains the DNA sequences for Ad2 cell transformation (Gallimore et al. 1974; van der Eb et al. 1977). All Ad2-transformed cells synthesize mRNA from this region (Flint et al. 1975; Bachenheimer and Darnell 1976; Chinnadurai et al. 1976, 1978), as well as proteins that are immunologically related to several Ad2 early proteins (Gilead et al. 1976; Levinson and Levine 1977; Johansson et al. 1978; Wold and Green 1979). These observations, and the isolation of Ad2 transformationdefective mutants (Graham et al. 1978) that map in E1 (Frost and Williams 1978), suggest that proteins coded by this region play a role in Ad2 cell transformation. Two approaches were used to identify these proteins and to map their genes. First, in vitro translation of viral mRNA selected by hybridization to DNA restriction fragments mapped several 38K-51K polypeptides (Lewis et al. 1976; Lupker et al. 1977; Harter and Lewis 1978; Halbert et al. 1979), a 14K polypeptide (Lupker et al. 1977) and a 28K polypeptide (Halbert et al. 1979) within map units 1.5--4.5 (designated E1A), a 15K polypeptide (Lewis et al.1976; Halbert et al. 1979) and a 52K polypeptide (Halbert et al. 1979) within map units 4.5-11 (designated E1B), and a 12K polypeptide within map units 9.5-11 (Pettersson and Mathews 1977). A second approach to identifying and mapping E1 polypeptides is immunoprecipitation of [3SS] methionine-labeled polypeptides using antisera against Ad2-or Ad5-transformed cells that retain only El. We precipitated 53K and 15K polypeptides with antiserum against FI7 cells (Gilead et ai. 1976), a line of Ad2-transformed rat cells (Gallimore 1974). Levinson and Levine (1977) identified an Ad5-specific 58K polypeptide.