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

Journal article

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.

Authors: Fisher, F; Goding, C

• Publication status: Published
• Journal: EMBO journal
• Volume: 11
• Issue: 11
• Pages: 4103-4109
• Publication date: 1992-11-01
• EISSN: 1460-2075
• ISSN: 0261-4189
• Language: English
• Keywords: Transcription Factors; Methionine; Sequence Homology, Nucleic Acid; Mutagenesis, Site-Directed; Base Sequence; DNA-Binding Proteins; Saccharomyces cerevisiae; Fungal Proteins; Oligonucleotide Probes; Genes, Fungal; Phosphoric Monoester Hydrolases; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; Molecular Sequence Data; Protein Conformation; Amino Acid Sequence; Binding Sites; Saccharomyces cerevisiae Proteins