The conjugation of SUMO to the transcription factor MYC2 functions in blue light-mediated seedling development in Arabidopsis

Srivastava, Moumita; Srivastava, Anjil Kumar; Roy, Dipan; Mansi, Mansi; Gough, Catherine; Bhagat, Prakash Kumar; Zhang, Cunjin; Sadanandom, Ari

Abstract

A key function of photoreceptor signaling is the coordinated regulation of a large number of genes to optimize plant growth and development. The basic helix loop helix (bHLH) transcription factor MYC2 is crucial for regulating gene expression in Arabidopsis thaliana during development in blue light. Here we demonstrate that blue light induces the SUMOylation of MYC2. Non-SUMOylatable MYC2 is less effective in suppressing blue light-mediated photomorphogenesis than wild-type (WT) MYC2. MYC2 interacts physically with the SUMO proteases SUMO PROTEASE RELATED TO FERTILITY1 (SPF1) and SPF2. Blue light exposure promotes the degradation of SPF1 and SPF2 and enhances the SUMOylation of MYC2. Phenotypic analysis revealed that SPF1/SPF2 function redundantly as positive regulators of blue light-mediated photomorphogenesis. Our data demonstrate that SUMO conjugation does not affect the dimerization of MYC transcription factors but modulates the interaction of MYC2 with its cognate DNA cis-element and with the ubiquitin ligase Plant U-box 10 (PUB10). Finally, we show that non-SUMOylatable MYC2 is less stable and interacts more strongly with PUB10 than the WT. Taken together, we conclude that SUMO functions as a counterpoint to the ubiquitin-mediated degradation of MYC2, thereby enhancing its function in blue light signaling.

Citation

Srivastava, M., Srivastava, A. K., Roy, D., Mansi, M., Gough, C., Bhagat, P. K., Zhang, C., & Sadanandom, A. (2022). The conjugation of SUMO to the transcription factor MYC2 functions in blue light-mediated seedling development in Arabidopsis. The Plant Cell, 34(8), 2892-2906. https://doi.org/10.1093/plcell/koac142

• Journal Article Type: Article
• Acceptance Date: May 4, 2022
• Online Publication Date: May 14, 2022
• Publication Date: 2022-08
• Deposit Date: Jul 21, 2022
• Publicly Available Date: Feb 8, 2023
• Journal: The Plant Cell
• Print ISSN: 1040-4651
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 34
• Issue: 8
• Pages: 2892-2906
• DOI: https://doi.org/10.1093/plcell/koac142
• Public URL: https://durham-repository.worktribe.com/output/1196972