1. SlCPK27 cross-links SlHY5 and SlPIF4 in brassinosteroid-dependent photo- and thermo-morphogenesis in tomato.
- Author
-
Changan Zhu, Zhangjian Hu, Chaoyi Hu, Hongxue Ma, Jie Zhou, Xiaojian Xia, Kai Shi, Foyer, Christine H., Jingquan Yu, and Yanhong Zhou
- Subjects
- *
CALCIUM-dependent protein kinase , *GENETIC transcription , *PLANT regulators , *TOMATOES , *PLANT photomorphogenesis - Abstract
ELONGATED HYPOCOTOYL5 (HY5) and PHYTOCHROME INTERACTING FACTORs (PIFs) are two types of important light-related regulators of plant growth, however, their interplay remains elusive. Here, we report that the activated tomato (Solanum lycopersicum) HY5 (SlHY5) triggers the transcription of a Calcium-dependent Protein Kinase SlCPK27. SlCPK27 interacts with and phosphorylates SlPIF4 at Ser-252 and Ser-308 phosphosites to promote its degradation. SlPIF4 promotes hypocotyl elongation mainly by activating the transcription of SlDWF, a key gene in brassinosteroid (BR) biosynthesis. Such a SlHY5-SlCPK27-SlPIF4-BR cascade not only plays a crucial role in photomorphogenesis but also regulates thermomorphogenesis. Our results uncover a previously unidentified mechanism that integrates Ca2+ signaling with the light signaling pathways to regulate plant growth by modulating BR biosynthesis in response to changes in ambient light and temperature. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF