Cysteines have a role in conformation of the UVR8 photoreceptor

Liao, X. and Jenkins, G. I. (2022) Cysteines have a role in conformation of the UVR8 photoreceptor. Plant Journal, 111(2), pp. 583-594. (doi: 10.1111/tpj.15841) (PMID:35608127)

Abstract

The UVR8 photoreceptor mediates plant responses to UV-B wavelengths. The UVR8 dimer dissociates into monomers following UV-B photoreception, a process accompanied by conformational changes that facilitate interaction of UVR8 with proteins that initiate responses. However, the importance of particular amino acids in maintaining UVR8 conformation and modulating protein interactions is poorly understood. Here we examine the roles of cysteine amino acids C231 and C335 in UVR8 structure and function. UVR8C231S,C335S mutant protein forms dimers and monomerises similarly to wild-type UVR8. UVR8C231S,C335S interacts with CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1) in plants to initiate photomorphogenic responses to UV-B, although the interaction is weaker when examined in yeast 2-hybrid assays. Similarly, the interaction of UVR8C231S,C335S with REPRESSOR OF UV-B PHOTOMORPHOGENESIS (RUP) proteins is weaker in both plants and yeast compared to wild-type UVR8. Re-dimerisation of UVR8 in plants, which is mediated by RUP proteins, occurs with reduced efficiency in UVR8C231S,C335S. Fluorescence Resonance Energy Transfer (FRET) analysis indicates that UVR8C231S,C335S has an altered conformation in plants, in that the N- and C-termini appear closer together, which may explain the altered protein interactions.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Liao, Xinyang and Jenkins, Professor Gareth
• Authors: Liao, X., and Jenkins, G. I.
• College/School: College of Medical Veterinary and Life Sciences > School of Molecular Biosciences
• Journal Name: Plant Journal
• Publisher: Wiley
• ISSN: 0960-7412
• ISSN (Online): 1365-313X
• Published Online: 24 May 2022
• Copyright Holders: Copyright © 2022 The Authors
• First Published: First published in Plant Journal 111(2): 583-594
• Publisher Policy: Reproduced under a Creative Commons License