Related Experiment Video
Updated: Aug 6, 2026

Investigating Interactions Between Histone Modifying Enzymes and Transcription Factors in vivo by Fluorescence Resonance Energy Transfer
Published on: October 14, 2022
An ACT-like domain participates in the dimerization of several plant basic-helix-loop-helix transcription factors
Antje Feller1, J Marcela Hernandez, Erich Grotewold
1Molecular, Cellular, and Developmental Biology Program, Ohio State University, Columbus, Ohio 43210, USA.
Abstract:
The maize basic-helix-loop-helix (bHLH) factor R belongs to a group of proteins with important functions in the regulation of metabolism and development through the cooperation with R2R3-MYB transcription factors. Here we show that in addition to the bHLH and the R2R3-MYB-interacting domains, R contains a dimerization region located C-terminal to the bHLH motif. This protein-protein interaction domain is important for the regulation of anthocyanin pigment biosynthesis by contributing to the recruitment of the C1 R2R3-MYB factor to the C1 binding sites present in the promoters of flavonoid biosynthetic genes. The R dimerization region bares structural similarity to the ACT domain present in several metabolic enzymes. Protein fold recognition analyses resulted in the identification of similar ACT-like domains in several other plant bHLH proteins. We show that at least one of these related motifs is capable of mediating homodimer formation. These findings underscore the function of R as a docking site for multiple protein-protein interactions and provide evidence for the presence of a novel dimerization domain in multiple plant bHLH proteins.
Related Concept Videos
Eukaryotic Transcription Activators
The binding domains are capable of recognizing and interacting with regulatory sequences on the DNA. These domains are...
Cooperative Binding of Transcription Regulators
Cooperative Binding of Transcription Regulators
Cell Signaling in Plants
General Transcription Factors
Co-activators and Co-repressors
