GONUTS has been updated to MW1.31 Most things seem to be working but be sure to report problems.

Have any questions? Please email us at ecoliwiki@gmail.com


Jump to: navigation, search

Loveys, DA, Streiff, MB and Kato, GJ (1996) E2A basic-helix-loop-helix transcription factors are negatively regulated by serum growth factors and by the Id3 protein. Nucleic Acids Res. 24:2813-20


Id3, a member of the Id multigene family of dominant negative helix-loop-helix transcription factors, is induced sharply in murine fibroblasts by serum growth factors. To identify relevant targets of Id3 activity, the yeast two-hybrid system was used to identify proteins that dimerize with Id3. Four murine cDNAs were identified in the screen, all of which encode helix-loop-helix proteins: E12, E47, ALF1 and Id4. Co-immunoprecipitation assays confirm that Id3 interacts with E12, E47 and two alternative splice products of ALF1 in vitro. Id3 disrupts DNA binding by these proteins in vitro and blocks transcriptional activation by these factors in cultured murine cells. Additionally, Id3 shows evidence of interacting with the related proteins E2-2 and MyoD, but not c-Myc. These results suggest that Id3 can function as a general negative regulator of the basic-helix-loop-helix family of transcription factors exemplified by the 'E' proteins and MyoD. Although it was previously suspected that E2A is constitutively expressed, our data indicate that E2A is induced in quiescent fibroblasts, by growth factor withdrawal but not by contact inhibition of cell proliferation. These observations extend the role of Id3 in the functional antagonism of E2A-class transcription factors, and suggest that E2A proteins may mediate growth inhibition.


PubMed PMC145994


3T3 Cells; Animals; Base Sequence; Basic Helix-Loop-Helix Transcription Factors; Cell Cycle; Cell Division; DNA Primers; DNA-Binding Proteins/genetics; DNA-Binding Proteins/metabolism; Gene Expression Regulation; Growth Substances/metabolism; Helix-Loop-Helix Motifs; Humans; Inhibitor of Differentiation Proteins; Mice; Molecular Sequence Data; MyoD Protein/genetics; MyoD Protein/metabolism; Neoplasm Proteins; Protein Binding; TCF Transcription Factors; Transcription Factor 7-Like 1 Protein; Transcription Factors/chemistry; Transcription Factors/genetics; Transcription Factors/metabolism; Transcription, Genetic



Gene product Qualifier GO ID GO term name Evidence Code with/from Aspect Notes Status

See also


See Help:References for how to manage references in GONUTS.