Transcription originating in the long terminal repeats of the endogenous mouse mammary tumor virus MTV-3 is activated in Stat5a-null mice and picks Up hitchhiking exons.

ABSTRACT: The enhancer within the long terminal repeats (LTRs) of acquired somatic mouse mammary tumor viruses (MMTV) can activate juxtaposed genes and induce mammary tumors. In contrast, germ line proviral MMTV genomes are integrated in the host genome and considered to be genetically confined transcription units. Here we demonstrate that transcription initiated in an MMTV provirus proceeds into flanking host sequences. We discovered multiple polyadenylated transcripts which are induced in Stat5a null mice. These range from 1.5 kb to more than 8 kb and are specifically expressed in mammary tissue from pregnant and lactating mice from the 129 but not C57BL/6 strain. The RNAs emanate from both LTRs of the endogenous MTV-3 provirus on chromosome 11 and proceed at least 10 kb into the juxtaposed genomi

SUBMITTER: Stegalkina SS 

PROVIDER: S-EPMC112887 | biostudies-literature | 1999 Oct

REPOSITORIES: biostudies-literature