en
Scientific article
Open access
English

Mechanisms of UV-B light-induced photoreceptor UVR8 nuclear localization dynamics

Published inNew phytologist, vol. 236, no. 5, p. 1824-1837
Publication date2022-12
First online date2022-09-21
Abstract

Light regulates the subcellular localization of plant photoreceptors, a key step in light signaling. Ultraviolet-B radiation (UV-B) induces the plant photoreceptor UV RESISTANCE LOCUS 8 (UVR8) nuclear accumulation, where it regulates photomorphogenesis. However, the molecular mechanism for the UV-B-regulated UVR8 nuclear localization dynamics is unknown. With fluorescence recovery after photobleaching (FRAP), cell fractionation followed by immunoblotting and co-immunoprecipitation (Co-IP) assays we tested the function of UVR8-interacting proteins including CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1), REPRESSOR OF UV-B PHOTOMORPHOGENESIS 1 (RUP1) and RUP2 in the regulation of UVR8 nuclear dynamics in Arabidopsis thaliana. We showed that UV-B-induced rapid UVR8 nuclear translocation is independent of COP1, which previously was shown to be required for UV-B-induced UVR8 nuclear accumulation. Instead, we provide evidence that the UV-B-induced UVR8 homodimer-to-monomer photo-switch and the concurrent size reduction of UVR8 enables its monomer nuclear translocation, most likely via free diffusion. Nuclear COP1 interacts with UV-B-activated UVR8 monomer, thereby promoting UVR8 nuclear retention. Conversely, RUP1and RUP2, whose expressions are induced by UV-B, inhibit UVR8 nuclear retention via attenuating the UVR8-COP1 interaction, allowing UVR8 to exit the nucleus. Collectively, our data suggest that UV-B-induced monomerization of UVR8 promotes its nuclear translocation via free diffusion. In the nucleus, COP1 binding promotes UVR8 monomer nuclear retention, which is counterbalanced by the major negative regulators RUP1 and RUP2.

eng
Keywords
  • Arabidopsis
  • UV RESISTANCE LOCUS 8
  • Nuclear import
  • Photomorphogenesis
  • Photoreceptor
  • Tomato
  • Arabidopsis Proteins / metabolism
  • Chromosomal Proteins, Non-Histone / metabolism
  • Signal Transduction
  • Arabidopsis / metabolism
  • Photoreceptors, Plant / metabolism
  • Ultraviolet Rays
  • Ubiquitin-Protein Ligases / metabolism
  • Gene Expression Regulation, Plant
Research group
Funding
  • National Natural Science Foundation of China - [31870261]
  • National Natural Science Foundation of China - [32070261]
  • National Natural Science Foundation of China - [32170246]
  • the Medicine and Engineering interdisciplinary Research Fund of SJTU - [YG2021ZD07]
  • China Postdoctoral Science Foundation - [2021M692072]
  • National Key Research and Development Program of China - [2018YFD1000800]
  • Natural Science Foundation of Shanghai - [22ZR1431300]
  • Swiss National Science Foundation - Perception and signalling of UV-B radiation in plants [31003A_175774]
Citation (ISO format)
FANG, Fang et al. Mechanisms of UV-B light-induced photoreceptor UVR8 nuclear localization dynamics. In: New phytologist, 2022, vol. 236, n° 5, p. 1824–1837. doi: 10.1111/nph.18468
Main files (1)
Article (Published version)
Secondary files (1)
Identifiers
ISSN of the journal0028-646X
135views
109downloads

Technical informations

Creation11/04/2022 9:50:00 AM
First validation11/04/2022 9:50:00 AM
Update time03/16/2023 8:53:42 AM
Status update03/16/2023 8:53:40 AM
Last indexation05/06/2024 11:59:44 AM
All rights reserved by Archive ouverte UNIGE and the University of GenevaunigeBlack