c-Jun enhancement of cyclic adenosine 3',5'-monophosphate response element-dependent transcription induced by transforming growth factor-beta is independent of c-Jun binding to DNA.
Journal Article (Journal Article)
Transforming growth factor-beta (TGFbeta) enhances transcription from reporter genes regulated by a single consensus cAMP-response element (CRE) upon transfection into the immortalized human keratinocyte cell line, HaCaT. Whereas both CRE-binding protein (CREB) and c-Jun present in extracts of unstimulated cells can complex with a CRE in gel-shift experiments, TGFbeta treatment increases the amount of c-Jun found in the complex. Overexpression of c-Jun is sufficient to increase CRE and GAL4-CREB-dependent transcription and mimics the stimulatory effects of TGFbeta on transcription from either reporter gene. Surprisingly, although a portion of CREB in unstimulated cells is phosphorylated on the activating serine residue, Ser-133, this level of phospho-CREB is not altered by TGFbeta treatment. In fact, the CREB-dependent transcriptional effects of TGFbeta or c-Jun do not require phosphorylation of Ser-133, although CREB-binding protein (CBP) is required as evidenced by the observation that the adenoviral oncoprotein E1A can block the effects of both agents. c-Jun enhancement of CRE or GAL4-CREB-dependent transcription neither requires the DNA-binding nor N-terminal domains of c-Jun. Collectively, these results are consistent with a model in which signaling pathways initiated by TGFbeta can stimulate CREB-dependent transcription by increasing the cellular concentration of c-Jun, which participates in activation of the CBP-containing transcription complex.
Full Text
Duke Authors
Cited Authors
- Hu, PP; Harvat, BL; Hook, SS; Shen, X; Wang, XF; Means, AR
Published Date
- December 1999
Published In
Volume / Issue
- 13 / 12
Start / End Page
- 2039 - 2048
PubMed ID
- 10598580
International Standard Serial Number (ISSN)
- 0888-8809
Digital Object Identifier (DOI)
- 10.1210/mend.13.12.0405
Language
- eng
Conference Location
- United States