Open AccessNucleotide sequence 5' of the chicken c-myc coding region: localization of a noncoding exon that is absent from myc transcripts in most avian leukosis virus-induced lymphomas.
Author(s) -
Cheng-Kon Shih,
Maxine L. Linial,
Maureen M. Goodenow,
William S. Hayward
Publication year - 1984
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.81.15.4697
Subject(s) - exon , biology , intron , coding region , microbiology and biotechnology , rna , genetics , nucleic acid sequence , gene
We have determined the nucleotide sequence of the 2.2-kilobase-pair region upstream of the chicken c-myc coding exons. Using RNA blot analysis, we have localized a noncoding exon to a region that is separated from the c-myc coding sequences by an intron of 700-800 base pairs. In most avian leukosis virus-induced lymphomas proviral integration has occurred within, or downstream of, the first exon, thus presumably displacing the regulatory sequences that normally control c-myc expression. More than 70% of the integration sites were clustered in a 250-base-pair region in the first intron, immediately preceding the coding sequences. Sequences from the upstream noncoding exon were absent from the myc transcripts in these lymphomas; RNA transcripts from the normal c-myc allele were not expressed at detectable levels.