Transcriptional products and DNA structure of endogenous avian proviruses.
Transcriptional products and DNA structure of endogenous avian proviruses.
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内源禽原病毒的转录产物和 DNA 结构。
DOI：
10.1101/sqb.1980.044.01.120
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发表时间：
1980
期刊：
影响因子：
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通讯作者：
Astrin,SM
中科院分区：
文献类型：
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作者：
Hayward,WS;Braverman,SB;Astrin,SM
与Rous相关病毒-0(RAV-0)密切相关的DNA序列存在于大多数未感染的鸡细胞的染色体材料中(Rosenthal等人。1971年；Baluda 1972；Varmus等人。1972年；内曼1973年)。尽管来自不同胚胎的细胞中内源性病毒DNA的数量相当稳定(通常约为2-6拷贝/细胞)，但前病毒基因的表达水平差异高达500倍(Payne和Chubb 1968；Weiss和Payne 1971；Hanafusa等人)。1972年；海沃德和哈纳福萨1973年)。表达模式是由基因决定的(回顾见罗宾逊1978年)，但人们对调控这种表达的机制知之甚少。不同胚胎的细胞根据其病毒群特异性(GS)抗原和鸡辅助因子(CHF)的含量可分为几种不同的表型(Payne和Chubb 1968；Weiss和Payne 1971；Hanafusa等人)。1972；Hanafusa et al.1974)，分别是gag基因和env基因的产物。在每种表型的细胞中积累的病毒特异性RNA水平与GS抗原和/或CHF的水平相关，这表明表达受到转录水平的控制，或者可能是mRNA的加工和周转(Hayward和Hanafusa 1973,1976)。还观察到RNA转录本中的质量差异(Wang等人。1977年)。例如，在GS+CHF+细胞中，病毒RNA的主要种类在pol1基因的很大一部分和Gag基因的一部分内被删除。这些细胞中的Gag-Poll多聚蛋白缺失了大部分聚合酶胰蛋白酶多肽和所有的p15多肽，OEisenman等。独立分离的内源性前病毒的鉴定(Astrin 1978；Astrin等人，本卷)有助于澄清上述表型差异的遗传基础。通过对白色来航鸡DNA的限制性内切酶分析，已鉴定出10多种不同的前病毒，它们的染色体居留位置不同。这些前病毒被指定为内源性病毒(EV)基因座，每个基因座都被分配了一个识别号。GS抗原和CHF表达的特征模式与特定内源性基因座的存在相关(参见表1)。
DNA sequences closely related to Rous-associated virus-0 (RAV-0) are present in the chromosomal material of most uninfected chicken cells (Rosenthal et al. 1971; Baluda 1972; Varmus et al. 1972; Neiman 1973). Although the amount of endogenous viral DNA in cells from different embryos is fairly constant (usually about 2-6 copies/cell), the level of proviral gene expression varies by as much as 500-fold (Payne and Chubb 1968; Weiss and Payne 1971; Hanafusa et al. 1972; Hayward and Hanafusa 1973). The patterns of expression are genetically determined (for review, see Robinson 1978), but little is known about the mechanism that regulates this expression. Cells from different embryos can be classified into several distinct phenotypes based on their content of viral group-specific (gs) antigen and chick helper factor (chf)(Payne and Chubb 1968; Weiss and Payne 1971; Hanafusa et al. 1972; Hanafusa et al. 1974), products of the gag and env genes, respectively. The levels of virus-specific RNA accumulating in cells of each phenotype correlate with the levels of gs antigen and/or chf, suggesting that expression is controlled at the level of transcription, or, possibly, mRNA processing and turnover (Hayward and Hanafusa 1973, 1976). Qualitative differences in the RNA transcripts have also been observed (Wang et al. 1977). In gs+ chf+ cells, for example, the major species of viral RNA is deleted within a substantial portion of the pol gene and part of the gag gene. The gag-pol polyprotein in these cells is missing most of the polymerase tryptic peptides and all of the p15 peptides OEisenman et al. 1978).The identification of independently segregating endogenous proviruses (Astrin 1978; Astrin et al., this volume) has helped to clarify the genetic basis of the phenotypic differences described above. More than ten distinct proviruses, differing in their chromosomal site of residence, have been identified by restriction endonuclease analysis of DNA from white leghorn chickens. These proviruses have been designated endogenous viral (ev) loci, and each locus has been assigned an identifying number. The characteristic patterns of gs antigen and chf expression correlate with the presence of specific endogenous loci (see Table 1).