Display Settings:


Send to:

Choose Destination
See comment in PubMed Commons below
J Virol. 1990 Feb;64(2):784-93.

Proviral insertions within the int-2 gene can generate multiple anomalous transcripts but leave the protein-coding domain intact.

Author information

  • 1Imperial Cancer Research Fund Laboratories, Lincoln's Inn Fields, London, United Kingdom.


We examined the effects of mouse mammary tumor virus integration on the multiple RNA transcripts expressed from the int-2 proto-oncogene in virally induced breast tumors. Proviral insertion either upstream or downstream of the gene could simultaneously activate transcription from three dissimilar int-2 promoters. In some tumors, the activating provirus lies within the transcription unit and disrupts the structures of the various RNAs. Insertions in the 5' region of the gene had complex effects depending on the orientation and position of the provirus relative to the three promoters and intron-exon boundaries. RNase protection experiments identified transcripts initiated in the viral long terminal repeat, at normal and cryptic sites in the int-2 sequences, and from cryptic promoters in an inverted provirus. AT the 3' end, insertions occurred within the untranslated trailer and provided alternative termination signals that substituted for one or both of the normal the poly(A) addition sites. However, in no instance, of the 20 tumors analyzed in detail, did a provirus perturb the presumed open reading frame of the gene. These data strongly implicate the normal product of the int-2 gene, which is related to the fibroblast growth factor family, as a contributory factor in virally induced mammary tumors.

[PubMed - indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk