Avian erythroblastosis virus E26: nucleotide sequence of the tripartite onc gene and of the LTR, and analysis of the cellular prototype of the viral ets sequence.
Avian erythroblastosis virus E26: nucleotide sequence of the tripartite onc gene and of the LTR, and analysis of the cellular prototype of the viral ets sequence.
复制标题
禽成红细胞增多症病毒E26：三联onc基因和LTR的核苷酸序列，以及病毒ets序列的细胞原型分析。
DOI：
10.1016/0042-6822(84)90378-7
复制
发表时间：
1984
期刊：
影响因子：
3.7
通讯作者：
Duesberg,P
中科院分区：
文献类型：
--
作者：
Nunn,M;Weiher,H;Bullock,P;Duesberg,P
禽成红细胞增多症病毒E26的完整5.7 kb前病毒已被分子克隆，用于与禽成髓细胞增多症病毒（AMV）和其他禽肿瘤病毒进行比较。E26和AMV仅转化造血细胞。两者都引起成髓细胞增多症，但E26也引起成红细胞增多症。原病毒DNA序列分析表明：（1）E26转化基因的三部分组成一个连续的阅读框架，包括272个gag、283个mybE和491个etscodons，共1046个密码子。在E26感染的细胞中未检测到亚基因组特异性mRNA。AMV的癌基因几乎完全由mybA序列组成，通过亚基因组mRNA表达，延伸到mybE的5′和3′末端。（ii）mybE与AMV的mybA同源物只有轻微的差异，与细胞原myb序列的差异更小，没有将两种病毒与原myb区分开的特征性突变。(iii)E26和AMV的长末端重复序列（LTR）的U 5区是共线的，仅在分散的点突变上不同。E26 LTR的U3区不同于AMV的U3区，但与禽癌病毒MH 2的U3区和布拉格劳斯肉瘤病毒（RSV）的U3区共线性且密切相关，除了22个RSV核苷酸的意外的16个核苷酸取代。在3′ LTR上游，E26的c区与RSV的c区有70个核苷酸相同，与AMV和MH 2的c区有20 - 30个核苷酸非常相似。由于E26、MH 2和RSV的U3非常密切相关，并且MH 2和RSV均未显示出特定的成红细胞嗜性，因此U3可能在E26的成红细胞嗜性中不起关键作用。用限制性内切酶消化的鸡DNA的电泳大小分析表明，总长度超过50 kb的DNA片段与viraletsDNA杂交。
An intact 5.7-kb provirus of the avian erythroblastosis virus E26 has been molecularly cloned for comparisons with avian myeloblastosis virus (AMV) and other avian tumor viruses. E26 and AMV transform hemopoietic cells exclusively. Both cause myeloblastosis, but E26 also causes erythroblastosis. Sequence analysis of the proviral DNA showed that: (i) The tripartite transforming gene of E26 forms a contiguous reading frame of 1046 codons, including 272gag, 283mybE, and 491etscodons. No subgenomicets-specific mRNA was detected in E26-infected cells. By contrast, theoncgene of AMV consists almost entirely of amybAsequence expressed via subgenomic mRNA that extends over the 5′ and 3′ ends ofmybE. (ii)mybEis only slightly diverged from themybAhomolog of AMV and even less from the cellular proto-mybsequence with no characteristic mutation that sets apart the two viruses from proto-myb. (iii) The U5 region of the long terminal repeat (LTR) of E26 and AMV are colinear and differ only in scattered point mutations. The U3 region of the E26 LTR is different from that of AMV but is colinear and closely related with that of avian carcinoma virus MH2 and also with that of Prague Rous sarcoma virus (RSV), except for an unexpected 16-nucleotide substitution of 22 RSV nucleotides. Upstream of the 3′ LTR, the c region of E26 appears to be the same as that of RSV for 70 nucleotides and very similar to those of AMV and MH2 for about 20 to 30 nucleotides. Since the U3s of E26, MH2 and RSV are very closely related and neither MH2 nor RSV show a particular erythroblast tropism, it is possible that the U3 does not play a critical role in the erythroblast tropism of E26. Electrophoretic size analyses of chicken DNA digested with restriction enzymes indicate that DNA fragments totaling over 50 kb hybridize with viraletsDNA.