basic helix-loop-helix

Function: - basic region forms half site for DNA-binding - most proteins with a helix-loop-helix (HLH) have an extra basic region of about 15 amino acid residues, adjacent to the HLH that specifically binds to DNA - bHLH proteins may be - class A (ubiquitous) - class B (tissue-specific) - members of the bHLH family bind variations on the core sequence 'CANNTG', also refered to as the E-box motif Structure: - the homodimerization or heterodimerization mediated by the HLH domain is independent of, but necessary for DNA binding - that is, two basic regions are required for DNA binding activity - HLH proteins lacking the basic domain function as negative regulators since they form heterodimers, but fail to bind DNA

General

basic DNA-binding motif helix-loop-helix (HLH)

Properties

MOTIF: basic DNA-binding motif helix-loop-helix NAME: helix-loop-helix FOR-BINDING-VIA: helix-loop-helix FOR-BINDING-OF: DNA motif FOR-BINDING-VIA: helix-loop-helix MISC-INFO: RECOGNITION-MOTIF :SEQUENCE CA--TG :REF " - Blackwell TK, Kretzner L, Blackwood EM, Eisenman RN, Weintraub H. Sequence-specific DNA binding by the c-Myc protein. Science. 1990 Nov 23;250(4984):1149-51. PMID: 2251503"

References

prosite :accession PS00038