Send to

Choose Destination
Proc Natl Acad Sci U S A. 2013 Jan 15;110(3):1113-8. doi: 10.1073/pnas.1214237110. Epub 2012 Dec 31.

Reversion of the Arabidopsis UV-B photoreceptor UVR8 to the homodimeric ground state.

Author information

Department of Botany and Plant Biology, Sciences III, University of Geneva, CH-1211 Geneva 4, Switzerland.


Plants require the UV-B photoreceptor UV resistance locus 8 (UVR8) for acclimation and survival in sunlight. Upon UV-B perception, UVR8 switches instantaneously from a homodimeric to monomeric configuration, which leads to interaction with the key signaling protein constitutively photomorphogenic 1 (COP1) and induction of UV-B-protective responses. Here, we show that UVR8 monomerization is reversible in vivo, restoring the homodimeric ground state. We also demonstrate that the UVR8-interacting proteins repressor of UV-B photomorphogenesis (RUP)1 and RUP2 mediate UVR8 redimerization independently of COP1. UVR8 redimerization consequently disrupts the UVR8-COP1 interaction, which halts signaling. Our results identify a key role of RUP1- and RUP2-mediated UVR8 redimerization in photoreceptor inactivation, a crucial process that regenerates reactivatable UVR8 homodimers.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center