Single amino acid substitutions alter helix-loop-helix protein specificity for bases flanking the core CANNTG motif.

AUTOR(ES)

Fisher, F

RESUMO

While all basic region/helix-loop-helix (bHLH) proteins bind the consensus CANNTG motif, other factors must be involved in determining regulatory specificity. In this report we show that bases outside this core 6 bp are involved in determining the specificity of binding. Thus, binding of the yeast bHLH protein PHO4, but not CPF-1, is inhibited by the presence of a T residue immediately 5' to their common CACGTG recognition sequence. PHO4 binding specificity is altered by mutation at any of three different positions in the basic region, including a single Glu to Asp substitution. The significance of these data for DNA-binding and transcription regulation by the bHLH family of transcription factors is discussed.

Documentos Relacionados

• Dual DNA binding specificity of ADD1/SREBP1 controlled by a single amino acid in the basic helix-loop-helix domain.
• Expression from the murine p53 promoter is mediated by factor binding to a downstream helix-loop-helix recognition motif.
• The WRPW motif of the hairy-related basic helix-loop-helix repressor proteins acts as a 4-amino-acid transcription repression and protein-protein interaction domain.
• Net (ERP/SAP2) one of the Ras-inducible TCFs, has a novel inhibitory domain with resemblance to the helix-loop-helix motif.
• HTF4: a new human helix-loop-helix protein.