title: Molecular organization of the chicken ets locus.
abstract: Chicken DNA segments homologous to the ets region from the transforming gene of avian erythroblastosis virus, E26, were molecularly cloned and shown to be almost identical to v-ets by sequence analysis. The transforming gene acids from two cell-derived sequences, myb and ets. Whereas the mammalian ets genes are present on two chromosomes, the chicken ets sequence is present as a single locus with v-ets homologous sequences found in nine regions over about 60 kb of genomic DNA. The major sequence difference between the v-ets and c-ets is found at the 3' end, resulting in different carboxy termini of p135 and the chicken proto-ets product. The chicken locus is primarily expressed in normal thymus cells as a 7.5-kb mRNA. The first two viral homologous regions are not found in this c-ets transcript or any other minor species, suggesting that they may not be true exons. Thus, the v-ets region of E26 demonstrates that two major structural differences may have occurred during the transduction of proto-ets sequences by the virus: (1) Truncation of sequences present at the 5' and 3' ends of the gene; and (2) Acquisition of noncoding proto-ets sequences into the virus. Either or both of these differences may be, in part, responsible for the oncogenic potential of this retrovirus.
authors.affiliation: Laboratory of Molecular Oncology, National Cancer Institute, Frederick, Maryland 21701-1013.
authors.forename: D K
authors.initials: DK
authors.lastname: Watson
authors.forename: M J
authors.initials: MJ
authors.lastname: McWilliams
authors.forename: T S
authors.initials: TS
authors.lastname: Papas
mesh_terms: D001355:Alpharetrovirus / Q000235:genetics; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002645:Chickens / Q000235:genetics*; D004247:DNA / Q000235:genetics; D005814:Genes, Viral; D008969:Molecular Sequence Data; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D050783:Proto-Oncogene Proteins c-ets; D011519:Proto-Oncogenes; D012191:Retroviridae Proteins / Q000235:genetics; D015682:Retroviridae Proteins, Oncogenic; D012689:Sequence Homology, Nucleic Acid; D014157:Transcription Factors
chemical_list: D011518:Proto-Oncogene Proteins; D050783:Proto-Oncogene Proteins c-ets; D012191:Retroviridae Proteins; D015682:Retroviridae Proteins, Oncogenic; D014157:Transcription Factors; C050379:oncogene proteins v-ets; D004247:DNA