Arabidopsis thaliana MYC2 and MYC3 Are Involved in Ethylene-Regulated Hypocotyl Growth as Negative Regulators

• Published in: International journal of molecular sciences 2024-08, Vol.25 (15), p.8022
• Main Authors: Li, Yuke, Cheng, Ying, Wei, Fan, Liu, Yingxiao, Zhu, Ruojia, Zhao, Pingxia, Zhang, Jing, Xiang, Chengbin, Kang, Erfang, Shang, Zhonglin
• Format: Article
• Language: English
• Subjects: Arabidopsis - genetics; Arabidopsis - growth & development; Arabidopsis - metabolism; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Arabidopsis thaliana; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors - genetics; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors - metabolism; Basic-Leucine Zipper Transcription Factors - genetics; Basic-Leucine Zipper Transcription Factors - metabolism; Biosynthesis; Cellular signal transduction; DNA binding proteins; DNA-Binding Proteins - genetics; DNA-Binding Proteins - metabolism; ERF1; Ethylene; Ethylenes - metabolism; Flavonoids; Gene expression; Gene Expression Regulation, Plant; Genetic transcription; Growth; hypocotyl; Hypocotyl - genetics; Hypocotyl - growth & development; Hypocotyl - metabolism; Iron; Kinases; Metabolites; MYC2; MYC3; Peptide Termination Factors; Physiology; Plant growth; Promoter Regions, Genetic; Seedlings - genetics; Seedlings - growth & development; Seedlings - metabolism; Seeds; Senescence; Signal Transduction; Trans-Activators; Transcription factors; Transcription Factors - genetics; Transcription Factors - metabolism
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms25158022

The ethylene-regulated hypocotyl elongation of involves many transcription factors. The specific role of MYC transcription factors in ethylene signal transduction is not completely understood. The results here revealed that two MYCs, MYC2 and MYC3, act as negative regulators in ethylene-suppressed hypocotyl elongation. Etiolated seedlings of the loss-of-function mutant of MYC2 or MYC3 were significantly longer than wild-type seedlings. Single- or double-null mutants of MYC2 and MYC3 displayed remarkably enhanced response to ACC(1-aminocyclopropane-1-carboxylate), the ethylene precursor, compared to wild-type seedlings. MYC2 and MYC3 directly bind to the promoter zone of ERF1, strongly suppressing its expression. Additionally, EIN3, a key component in ethylene signaling, interacts with MYC2 or MYC3 and significantly suppresses their binding to ERF1's promoter. MYC2 and MYC3 play crucial roles in the ethylene-regulated expression of functional genes. The results revealed the novel role and functional mechanism of these transcription factors in ethylene signal transduction. The findings provide valuable information for deepening our understanding of their role in regulating plant growth and responding to stress.