ID (inhibitor of DNA binding) HLH proteins lack a basic DNA-binding domain but are able to form heterodimers with other HLH proteins, thereby inhibiting DNA binding. ID-3 inhibits the binding of E2A-containing protein complexes to muscle creatine kinase E-box enhancer. May inhibit other transcription factors. Induced by phorbol 12-myristate 13-acetate (PMA). Interacts with COPS5 and COPS7A. Homodimer, and heterodimer with other HLH proteins. Note: This description may include information from UniProtKB.
Protein type: DNA binding protein; Transcription, coactivator/corepressor
Molecular Function: protein dimerization activity; protein domain specific binding; transcription factor binding; transcription corepressor activity; transcription factor activity
Biological Process: muscle development; central nervous system development; transcription, DNA-dependent; regulation of cell cycle; positive regulation of apoptosis; negative regulation of transcription factor activity; multicellular organismal development; heart development; negative regulation of transcription from RNA polymerase II promoter; notochord development; odontogenesis; neuron differentiation; epithelial cell differentiation; response to wounding; negative regulation of osteoblast differentiation; negative regulation of transcription, DNA-dependent; metanephros development; regulation of DNA replication
Alt. Names/Synonyms: 1R21; BHLHB25; Class B basic helix-loop-helix protein 25; DNA-binding protein inhibitor ID-3; HEIR-1; HEIR1; Helix-loop-helix protein HEIR-1; ID-like protein inhibitor HLH 1R21; ID3; Inhibitor of DNA binding 3; inhibitor of DNA binding 3, dominant negative helix-loop-helix protein
SS: The number of records in which this modification site was determined using site-specific methods. SS methods include amino acid sequencing, site-directed mutagenesis, modification site-specific antibodies, specific MS strategies, etc.