Toggle Main Menu Toggle Search

Open Access padlockePrints

Regulation of TCF ETS-domain transcription factors by helix-loop-helix motifs

Lookup NU author(s): Dr Paula Yates

Downloads


Abstract

DNA binding by the ternary complex factor (TCF) subfamily of ETS-domain transcription factors is tightly regulated by intramolecular and intermolecular interactions. The helix-loop-helix (HLH)-containing Id proteins are trans-acting negative regulators of DNA binding by the TCFs. In the TCF, SAP-2/Net/ERP, intramolecular inhibition of DNA binding is promoted by the cis-acting NID region that also contains an HLH-like motif. The NID also acts as a transcriptional repression domain. Here, we have studied the role of HLH motifs in regulating DNA binding and transcription by the TCF protein SAP-1 and how Cdk-mediated phosphorylation affects the inhibitory activity of the Id proteins towards the TCFs. We demonstrate that the NID region of SAP-1 is an autoinhibitory motif that acts to inhibit DNA binding and also functions as a transcription repression domain. This region can be functionally replaced by fusion of Id proteins to SAP-1, whereby the Id moiety then acts to repress DNA binding in cis. Phosphorylation of the Ids by cyclin-Cdk complexes results in reduction in protein-protein interactions between the Ids and TCFs and relief of their DNA-binding inhibitory activity. In revealing distinct mechanisms through which HLH motifs modulate the activity of TCFs, our results therefore provide further insight into the role of HLH motifs in regulating TCF function and how the inhibitory properties of the trans-acting Id HLH proteins are themselves regulated by phosphorylation.


Publication metadata

Author(s): Stinson J, Inoue T, Yates P, Clancy A, Norton JD, Sharrocks AD

Publication type: Article

Publication status: Published

Journal: Nucleic Acids Research

Year: 2003

Volume: 31

Issue: 16

Pages: 4717-4728

Date deposited: 08/03/2012

ISSN (print): 0305-1048

ISSN (electronic): 1362-4954

Publisher: Oxford University Press

URL: http://dx.doi.org/10.1093/nar/gkg689

DOI: 10.1093/nar/gkg689

PubMed id: 12907712


Altmetrics

Altmetrics provided by Altmetric


Share