Journal Article

Conserved and non-conserved functions of the rice homologs of the Arabidopsis trichome initiation-regulating MBW complex proteins

Wang, Yating, Wang, Shucai, Wang, Xutong, Zheng, Kaijie

2021

Overview

Background Trichome initiation in Arabidopsis is regulated by a MYB-bHLH-WD40 (MBW) transcriptional activator complex formed by the R2R3 MYB transcription factor GLABRA1 (GL1), MYB23 or MYB82, the bHLH transcription factor GLABRA3 (GL3), ENHANCER OF GLABRA3 (EGL3) or TRANSPARENT TESTA8 (TT8), and the WD40-repeat protein TRANSPARENT TESTA GLABRA1 (TTG1). However, the functions of the rice homologs of the MBW complex proteins remained uncharacterized. Results Based on amino acid sequence identity and similarity, and protein interaction prediction, we identified OsGL1s, OsGL3s and OsTTG1s as rice homologs of the MBW complex proteins. By using protoplast transfection, we show that OsGL1D, OsGL1E, OsGL3B and OsTTG1A were predominantly localized in the nucleus, OsGL3B functions as a transcriptional activator and is able to interact with GL1 and TTG1. By using yeast two-hybrid and protoplast transfection assays, we show that OsGL3B is able to interact with OsGL1E and OsTTG1A, and OsGL1E and OsTTG1A are also able to interact with GL3. On the other hand, we found that OsGL1D functions as a transcription activator, and it can interact with GL3 but not OsGL3B. Furthermore, our results show that expression of OsTTG1A in the ttg1 mutant restored the phenotypes including alternations in trichome and root hair formation, seed color, mucilage production and anthocyanin biosynthesis, indicating that OsTTG1A and TTG1 may have similar functions. Conclusion These results suggest that the rice homologs of the Arabidopsis MBW complex proteins are able to form MBW complexes, but may have conserved and non-conserved functions.

• Publisher: BioMed Central,BioMed Central Ltd,Springer Nature B.V,BMC
• Subject: Agricultural research / Agriculture / Alternations / Amino acid sequence / amino acid sequences / Amino acids / Anthocyanins / Arabidopsis / Biomedical and Life Sciences / Biosynthesis / Development and cell biology / Genetic aspects / Genetic regulation / Helix-loop-helix proteins (basic) / Homology / Life Sciences / Localization / MBW complex / Mucilage / mucilages / mutants / Phenotypes / Phylogenetics / Physiological aspects / Plant proteins / Plant Sciences / prediction / Proteins / protoplasts / Regulation / Research Article / Rice / root hairs / seed color / sequence analysis / testa / transactivators / Transcription factor / Transcription factors / Transfection / Tree Biology / Trichome initiation / Trichomes / two hybrid system techniques / Yeast