The Receptor-Like Cytoplasmic Kinase STRK1 Phosphorylates and Activates CatC, Thereby Regulating H₂O₂ Homeostasis and Improving Salt Tolerance in Rice

Abstract

Salt stress can significantly affect plant growth and agricultural productivity. Receptor-like kinases (RLKs) are believed to play essential roles in plant growth, development, and responses to abiotic stresses. Here, we identify a receptor-like cytoplasmic kinase, salt tolerance receptor-like cytoplasmic kinase 1 (STRK1), from rice () that positively regulates salt and oxidative stress tolerance. Our results show that STRK1 anchors and interacts with CatC at the plasma membrane via palmitoylation. CatC is phosphorylated mainly at Tyr-210 and is activated by STRK1. The phosphorylation mimic form CatC exhibits higher catalase activity both in vitro and in planta, and salt stress enhances STRK1-mediated tyrosine phosphorylation on CatC. Compared with wild-type plants, -overexpressing plants exhibited higher catalase activity and lower accumulation of HO as well as higher tolerance to salt and oxidative stress. Our findings demonstrate that STRK1 improves salt and oxidative tolerance by phosphorylating and activating CatC and thereby regulating HO homeostasis. Moreover, overexpression of in rice not only improved growth at the seedling stage but also markedly limited the grain yield loss under salt stress conditions. Together, these results offer an opportunity to improve rice grain yield under salt stress.

Whole‐genome analysis identifying candidate genes of altitude adaptive ecological thresholds in yak populations

“…Another gene, PDE4D, also known as STRK1, is less well researched in animals but has been identified as a gene that can improve the salt tolerance of rice (Zhou et al, ). What's more, it has been determined that sudden exposure to high altitudes can cause strokes.…”

BAK1 Mediates Light Intensity to Phosphorylate and Activate Catalases to Regulate Plant Growth and Development

“…Given the fact that the phosphorylation of BAK1 is generally necessary for its potential activation of signaling, such as BR signaling [21,22] and innate immune signaling [46,47], we speculate that high light enhances phosphorylation of BAK1 for its activity potential, which in turn phosphorylates CAT1/2/3. It is notable that in Arabidopsis after CAT3 is phosphorylated by a calcium-dependent protein kinase, the catalytic activity of CAT3 was significantly enhanced [48], and in rice, the RLCK protein STRK1 phosphorylates CatC to stimulate its activity to regulate H 2 O 2 homeostasis and improve salt tolerance [49]. Thus, our results give rise to a hypothesis that phosphorylation of CATs by BAK1 results in the activation of CATs to scavenge H 2 O 2 , consequently leading to a reduction in H 2 O 2 levels.…”

VAMP711 Is Required for Abscisic Acid-Mediated Inhibition of Plasma Membrane H+-ATPase Activity

“…Intriguingly, studies with other proteins also showed similar phenomena. For example, catalase proteins localize in peroxisomes (Apel and Hirt, 2004); however, under salt and drought stresses, the plasma membrane proteins salt tolerance receptor-like cytoplasmic kinase1 (Zhou et al, 2018) and Calcium Protein Kinase8 (Zou et al, 2015) interact with, phosphorylate, and activate Catalase C (in rice) and Catalase 3 (in Arabidopsis) on the plasma membrane, respectively. Therefore, it is possible that the VAMP711 protein could be translocated to the plasma membrane through certain unclear mechanisms or under certain physiological conditions.…”