Key message: OsPUB41 plays a negative role in drought stress response through the mediation of OsUBC25 and interacts with OsCLC6, suggesting a putative substrate. Abstract: The notable expansion of Plant U-Box E3 ligases (PUB), compared with those in mammals, implies that PUB proteins have evolved to perform plant-specific functions. OsPUB41, a potential ortholog of CMPG1, was recently reported to regulate the cell wall degrading enzyme (CWDE)-induced innate immune response in rice. Here, we characterized the OsPUB41 gene, which encodes a dual-localized cytosolic and nuclear U-box E3 ligase in rice. OsPUB41 expression was specifically induced by dehydration among various abiotic stresses and abscisic acid (ABA) treatments. Furthermore, we revealed that the core U-box motif of OsPUB41 possesses the E3 ligase activity that can be activated by OsUBC25 in rice. The Ubi:RNAi-OsPUB41 knock-down and ospub41 suppression mutant plants exhibited enhanced tolerance to drought stress compared with the wild-type rice plants in terms of transpirational water loss, long-term dehydration response, and chlorophyll content. Moreover, the knock-down or suppression of the OsPUB41 gene did not cause adverse effect on rice yield-related traits. Yeast two-hybrid and an in vitro pull-down analyses revealed that OsCLC6, a chloride channel, is a putative substrate of OsPUB41. Overall, these results suggest that OsPUB41 acts as a negative regulator of dehydration conditions and interacts with OsCLC6, implying that it is a substrate of OsPUB41.
Bibliographical noteFunding Information:
This work was supported by grants from the Next-Generation BioGreen 21 Program for Agriculture and Technology Development [Project Numbers PJ01113801 (NCGC) and PJ01334901 (SSAC)] funded by the Rural Development Administration and the Basic Science Research Program (Project Number 2018R1A6A1A03025607) through the National Research Foundation (NRF) funded by the Ministry of Education, South Korea to WTK and the Young Scientist Grants Program (Project Number NRF-2020R1C1C1014389) to DHS.
© 2021, The Author(s), under exclusive licence to Springer Nature B.V.
All Science Journal Classification (ASJC) codes
- Agronomy and Crop Science
- Plant Science