Transcriptional analysis of the leading region in F plasmid DNA transfer.

Transcriptional activity associated with the leading region (53.8-66.7F) in F DNA transfer has been shown by RNA-DNA hybridization studies to occur on the anterior segment extending from 59.4 to 66.7F. Promoter-probe analysis of cloned leading region segments detected two promoters within the transcribed portion of the leading region. The promoter active across the 64.7F EcoRI site on the transferred F strand was associated with the expression of two polypeptides, 6d and 13.5p, located between 64.7-66.6F. However, no definite role could be ascribed to the second promoter operative through the 66.6F Bg/II site located in close proximity to oriT, the origin of transfer.