Abstract |
An inducible bovine KIV* keratin gene promoter was used to target expression of latent or activated transforming growth factor beta 1 ( TGF beta 1) to keratinocytes in transgenic mice. This short (2.2-kb) keratin 6 (K6) promoter element was generally silent in untreated animals but was induced in keratinocytes when placed in culture or, in vivo, in response to hyperplasia that follows topical application of the tumor promoter, 12-O-tetradecanoylphorbol-13-acetate. All of the K6-TGF beta 1 transgenic lines studied showed attenuation of the basal keratinocyte proliferative response to 12-O-tetradecanoylphorbol-13-acetate as a consequence of inducible TGF beta 1 gene expression. One of the six lines studied showed constitutive transgene expression at low levels in the skin, and this line had a 2- to 3-fold increase in epidermal DNA labeling index over control mice. Although in vitro TGF beta 1 is known to be a potent negative regulator of epithelial cell proliferation, in vivo TGF beta 1 has complex biological activities and can act as either a positive or negative regulator of keratinocyte proliferation.
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Authors | D J Fowlis, W Cui, S A Johnson, A Balmain, R J Akhurst |
Journal | Cell growth & differentiation : the molecular biology journal of the American Association for Cancer Research
(Cell Growth Differ)
Vol. 7
Issue 5
Pg. 679-87
(May 1996)
ISSN: 1044-9523 [Print] United States |
PMID | 8732677
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Receptors, Transforming Growth Factor beta
- Transforming Growth Factor beta
- Keratins
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Topics |
- Animals
- Cattle
- Cell Death
(physiology)
- Cell Division
(physiology)
- Gene Expression Regulation
(physiology)
- Keratinocytes
(physiology)
- Keratins
(genetics)
- Mice
- Mice, Transgenic
- Promoter Regions, Genetic
(physiology)
- Receptors, Transforming Growth Factor beta
(genetics)
- Skin
(cytology, ultrastructure)
- Transforming Growth Factor beta
(genetics)
- Transgenes
(physiology)
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