Papas T S, Kan N C, Watson D K, Flordellis C, Lautenberger J A, Psallidopoulos M C, Rovigatti U G, Samuel K P, Ascione R, Duesberg P H
Anticancer Res. 1985 Jan-Feb;5(1):73-9.
The 5.2-kilobase (kb) RNA genome of avian carcinoma virus MH2 has the genetic structure 5' - delta gag (0.2 kb)-mht (1.2 kb)-myc (1.4 kb)-c(0.4 kb)-poly (A) (0.2 kb)-3'. delta gag is a partial retroviral core protein, mht and myc are cell-derived MH2-specific sequences, and c is the 3'-terminal retroviral vector sequence. the following results were obtained from the complete nucleotide sequences of the mht and myc genes in MH2. (i) delta gag-mht forms a hybrid gene with a contiguous reading frame of 2682 nucleotides that terminates with a stop codon near the 3' end of the mht gene. The 3' 969 nucleotides of mht up to the stop codon are 80% sequence related to the onc-specific raf sequence of murine sarcoma virus 3611 (MSV 3611) (94% homologous at the deduced amino acid level). (ii) The myc coding region in MH2 is preceded by 181 nucleotides derived from the intron immediately upstream from the second exon of the chicken cellular proto-myc gene, followed by an RNA splice acceptor site shared with the proto-myc gene, followed by an RNA splice acceptor site shared with the proto-myc, beyond which it is colinear up to a 3'-termination codon and 40 noncoding nucleotides with the myc sequences of avian retrovirus MC29 and chicken proto-myc. Thus, myc forms, together with a 5' retroviral exon, a second MH2-specific gene. It is concluded that MH2 contains two genes with oncogenic potential, the delta gag-mht gene, which is closely related to the delta gag-raf transforming gene of MSV 3611, and the myc gene, which is related to the transforming gene of MC29. Furthermore, it may be concluded that the cellular proto-onc genes, which on sequence transduction become viral onc genes, are a small group because among the 19 known onc sequences, 5 are shared by different taxonomic groups of viruses of which the mht/raf homology is the closest so far.
禽癌病毒MH2的5.2千碱基（kb）RNA基因组具有5'-δgag（0.2 kb）-mht（1.2 kb）-myc（1.4 kb）-c（0.4 kb）-poly（A）（0.2 kb）-3'的基因结构。δgag是部分逆转录病毒核心蛋白，mht和myc是细胞来源的MH2特异性序列，c是3'端逆转录病毒载体序列。以下结果来自于MH2中mht和myc基因的完整核苷酸序列。（i）δgag-mht形成一个杂合基因，其连续阅读框为2682个核苷酸，在mht基因3'端附近以终止密码子结束。mht的3'端969个核苷酸直至终止密码子与鼠肉瘤病毒3611（MSV 3611）的癌特异性raf序列有80%的序列相关性（在推导的氨基酸水平上同源性为94%）。（ii）MH2中的myc编码区之前有181个核苷酸，来源于鸡细胞原癌基因第二个外显子上游紧邻的内含子，接着是与原癌基因共享的RNA剪接受体位点，再接着是与原癌基因共享的RNA剪接受体位点，在此之后它与禽逆转录病毒MC29和鸡原癌基因的myc序列共线性，直至3'端终止密码子和40个非编码核苷酸。因此，myc与5'端逆转录病毒外显子一起形成了第二个MH2特异性基因。得出的结论是，MH2含有两个具有致癌潜力的基因，即与MSV 3611的δgag-raf转化基因密切相关的δgag-mht基因，以及与MC29的转化基因相关的myc基因。此外，可以得出结论，细胞原癌基因在序列转导后成为病毒癌基因，它们是一个小群体，因为在19个已知的癌序列中，有5个被不同分类群的病毒共享，其中mht/raf同源性是迄今为止最接近的。
