ID1
Protein-coding gene in the species Homo sapiens
From Wikipedia, the free encyclopedia
DNA-binding protein inhibitor ID-1 is a protein that in humans is encoded by the ID1 gene.[5][6]
Function
The protein encoded by this gene is a helix-loop-helix (HLH) protein that can form heterodimers with members of the basic HLH family of transcription factors.[5] The encoded protein has no DNA binding activity and therefore can inhibit the DNA binding and transcriptional activation ability of basic HLH proteins with which it interacts.[5] This protein may play a role in cell growth, senescence, and differentiation.[7][8][9] Two transcript variants encoding different isoforms have been found for this gene.[10]
Interactions
ID1 has been shown to interact weakly with MyoD[5][11][12][13][14][15][16] but very tightly with ubiquitously expressed E proteins.[17] E proteins heterodimerize with tissue restricted bHLH proteins such as Myod, NeuroD, etc. to form active transcription complexes so by sequestering E proteins, Id proteins can inhibit tissue restricted gene expression in multiple cell lineages using the same biochemical mechanism. Other interacting partners include CASK.[18]
Clinical significance
ID1 can be used to mark endothelial progenitor cells which are critical to tumor growth and angiogenesis.[19][20] Targeting ID1 results in decreased tumor growth.[21][22] ID1 has been shown to be targeted by cannabidiol in certain gliomas and breast cancers.[23][24]