The Jasmonate-ZIM-Domain Proteins Interact with the WD-Repeat/bHLH/MYB Complexes to Regulate Jasmonate-Mediated Anthocyanin Accumulation and Trichome Initiation in Arabidopsis thaliana

• Published in: The Plant cell 2011-05, Vol.23 (5), p.1795-1814
• Main Authors: Qi, Tiancong, Song, Susheng, Ren, Qingcuo, Wu, Dewei, Huang, Huang, Chen, Yan, Fan, Meng, Peng, Wen, Ren, Chunmei, Xie, Daoxin
• Format: Article
• Language: English
• Subjects: Accumulation; Amino Acid Motifs; Anthocyanins - metabolism; Arabidopsis - genetics; Arabidopsis - metabolism; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Basic Helix-Loop-Helix Transcription Factors - genetics; Basic Helix-Loop-Helix Transcription Factors - metabolism; Biosynthesis; Cyclopentanes - metabolism; DNA-Binding Proteins - genetics; DNA-Binding Proteins - metabolism; Fertility; Fluorescence; Gene expression regulation; Gene Expression Regulation, Plant; Nuclear Proteins - genetics; Nuclear Proteins - metabolism; Oxylipins - metabolism; Phenotype; Plant cells; Plant Growth Regulators - metabolism; Plants; Plants, Genetically Modified - genetics; Plants, Genetically Modified - metabolism; Protein Structure, Tertiary; Proteins; Repressor Proteins - genetics; Repressor Proteins - metabolism; Seedlings; Signal Transduction - physiology; Transcription factors; Transcription Factors - genetics; Transcription Factors - metabolism; Transcription, Genetic; Transcriptional regulatory elements; Trichomes
• ISSN: 1040-4651; 1532-298X
• DOI: 10.1105/tpc.111.083261

Jasmonates (JAs) mediate plant responses to insect attack, wounding, pathogen infection, stress, and UV damage and regulate plant fertility, anthocyanin accumulation, trichome formation, and many other plant developmental processes. Arabidopsis thaliana Jasmonate ZIM-domain (JAZ) proteins, substrates of the CORONATINE INSENSITIVE1 (COl1)-based SCF COl ¹ complex, negatively regulate these plant responses. Little is known about the molecular mechanism for JA regulation of anthocyanin accumulation and trichome initiation. In this study, we revealed that JAZ proteins interact with bHLH (Transparent Testa8, Glabra3 [GL3], and Enhancer of Glabra3 [EGL3]) and R2R3 MYB transcription factors (MYB75 and Glabra1), essential components of WD-repeat/bHLH/MYB transcriptional complexes, to repress JA-regulated anthocyanin accumulation and trichome initiation. Genetic and physiological evidence showed that JA regulates WD-repeat/bHLH/MYB complex-mediated anthocyanin accumulation and trichome initiation in a COl1-dependent manner. Overexpression of the MYB transcription factor MYB75 and bHLH factors (GL3 and EGL3) restored anthocyanin accumulation and trichome initiation in the col1 mutant, respectively. We speculate that the JA-induced degradation of JAZ proteins abolishes the interactions of JAZ proteins with bHLH and MYB factors, allowing the transcriptional function of WD-repeat/bHLH/MYB complexes, which subsequently activate respective downstream signal cascades to modulate anthocyanin accumulation and trichome initiation.