期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1981
卷号:78
期号:1
页码:100-104
DOI:10.1073/pnas.78.1.100
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:The 5' termini of the principal early mRNAs produced in cells transformed by wild-type simian virus 40 lie 21-25 nucleotides downstream from an A-T-T-T-A-T sequence on the DNA template. The 5' termini of early mRNAs produced by five origin-defective mutants containing deletions downstream from the A-T-T-T-A-T sequence and one viable mutant dl892 with a deletion starting 15 nucleotides upstream from this sequence were determined by a method involving synthesis, separation, and determination of the sequences of DNAs complementary to 5' termini. Mutant dl892 produced early mRNAs with the same principal 5' termini as wild-type virus; the origin-defective mutants produced mRNAs with principal 5' termini shifted downstream by a distance equivalent to the length of the deleted DNA segment. These data suggest that a DNA sequence of 29 nucleotides, which includes the A-T-T-T-A-T sequence, contains a component(s) of a promoter for early transcription. This component functions in positioning the 5' ends of the principal early mRNAs 21-25 nucleotides downstream from the A-T-T-T-A-T sequence and acts independently of these downstream sequences.