Mode of proviral activation of a putative mammary oncogene (int-1) on mouse chromosome 15

@article{Nusse1984ModeOP,
  title={Mode of proviral activation of a putative mammary oncogene (int-1) on mouse chromosome 15},
  author={Roel Nusse and Albert van Ooyen and David R. Cox and Yuen Kai T Fung and Harold Varmus},
  journal={Nature},
  year={1984},
  volume={307},
  pages={131-136}
}
Most mammary carcinomas induced in C3H mice by the mouse mammary tumour virus (MMTV) bear a new proviral insertion within a highly conserved locus on chromosome 15 called int-1. A transcriptional unit within this locus is inactive in all tested normal tissues but expressed at low levels in mammary tumours with proviral insertions positioned on either the 5′ and 3′ sides of the gene. Transcription of the proviruses proceeds away from int-1; thus an indirect mechanism appears to activate… 
A putative int domain for mouse mammary tumor virus on mouse chromosome 7 is a 5' extension of int-2
TLDR
An additional example of proviral integration is described in which a provirus in a presumed enhancer-insertion mode 15 kilobases upstream of the int-2 promoters is capable of activating expression of the gene at levels typical of other virally induced mammary tumors.
Concerted activation of two potential proto-oncogenes in carcinomas induced by mouse mammary tumour virus
TLDR
The data suggest that int-1 and int-2 may act cooperatively in the genesis of mammary carcinomas, and because in five cases activation occurred in the apparent absence of an adjacent provirus, it is clear that other loci and mechanisms contribute to tumorigenesis.
The activation of cellular oncogenes by proviral insertion in murine mammary cancer.
  • R. Nusse
  • Biology
    Cancer treatment and research
  • 1988
In this chapter, I shall review our current knowledge of the mechanism of mammary oncogenesis by the Mouse Mammary Tumor Virus (MMTV), with particular emphasis on the activation of cellular oncogenes
The Role of Specific Regions for Proviral Integration in Mouse Mammary Tumor Virus (MMTV) Induced Tumors
In the workshop entitled “Viruses and Oncogenes” an effort was made to summarize the current knowledge on specific chromosomal regions involved in MMTV-induced mammary tumor formation. Two such
Retroviral insertional mutagenesis in murine mammary cancer
TLDR
It is proposed that int-1 is a cellular oncogene for mammary tumours, which encodes a protein that is highly conserved between mouse and man and is presumably caused by the transcriptional enhancer present on the MMTV long terminal repeat.
Molecular cloning and chromosomal assignment of the human homolog of int-1, a mouse gene implicated in mammary tumorigenesis
TLDR
The human homolog of this putative mammary oncogene is cloned and its structure is compared to that of the mouse gene by heteroduplex analysis.
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TLDR
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TLDR
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  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 1983
TLDR
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