RT Journal Article
SR Electronic
T1 PARAQUAT TOLERANCE3 is an E3 ligase and acts as a negative regulator of oxidative stress response
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 040543
DO 10.1101/040543
A1 Chao Luo
A1 Xiao-Teng Cai
A1 Jin Du
A1 Tao-Lan Zhao
A1 Peng-Fei Wang
A1 Ping-Xia Zhao
A1 Rui Liu
A1 Qi Xie
A1 Xiao-Feng Cao
A1 Cheng-Bin Xiang
YR 2016
UL http://biorxiv.org/content/early/2016/02/22/040543.abstract
AB Oxidative damage could be caused in plant cells when biotic and abiotic stresses are imposed. While the response to oxidative stress is well studied, little is known about how the activated response is switched off when oxidative stress is diminished. By studying Arabidopsis mutant paraquat tolerance3, we identified the genetic locus PARAQUAT TOLERANCE3 (PQT3) as a major negative regulator of oxidative stress tolerance. PQT3, encoding an E3 ligase, is rapidly down-regulated by oxidative stress. PQT3 has E3 ubiquitin ligase activity in ubiquitination assay. Subsequently, we identified PRMT4b as a PQT3-interacting protein. By histone methylation, PRMT4b may regulate the expression of APX1 and GPX1, encoding two key enzymes against oxidative stress. Moreover, PQT3 is able to recognize PRMT4b for targeted degradation via 26S proteasome. Therefore, we have identified PQT3 as an E3 ligase that acts as a negative regulator of activated response to oxidative stress.