APPENDIX E Complete Nucleotide Sequences of Three Retroviral Genomes and a Cellular onc Gene

Abstract

Three retroviral genomes have been entirely sequenced: Rous sarcoma virus (RSV), Moloney murine leukemia virus (Mo-MLV), and Moloney murine sarcoma virus (Mo-MSV). In addition, the complete nucleotide sequence of the cellular homolog of the oncogene carried by Mo-MSV, c-mos, has been determined. In all cases, the sequence of only one strand, the coding strand, is provided here. The sequences are written for a DNA copy—that is, Ts are used instead of Us. The proposed amino acid sequences for known genes are given; also, correlations with protein sequence will be discussed briefly in the legends for the individual sequences and in the section devoted to amino acid sequence (Appendix F).

1. The Complete Nucleotide Sequence of the Pr-C Strain of Rous Sarcoma Virus
The sequence is presented as a DNA version of the entire viral RNA genome. The sequence begins with the R sequence “R” at the 5′ end of the genome. The precise boundary between R and U₅ (here marked with an arrow) is dependent on the extent of the R sequence at the 3′ end of viral RNA (see Appendix D). The 3′ end of U₅ forms an imperfect inverted repeat with U₃ (12 of 15 bases); inverted repeats of this sort are present in the LTRs of all retroviruses (see Appendix D). A horizontal arrow marks the inverted repeat; the mismatched bases are indicated by boxes. Just beyond U₅ is the primer binding site (PBS). Approximately 280 bases beyond U₅ is the beginning of the gag coding...