The CRK5 and WRKY53 Are Conditional Regulators of Senescence and Stomatal Conductance in Arabidopsis

Abstract

In Arabidopsis thaliana, cysteine-rich receptor-like kinases (CRKs) constitute a large group of membrane-localized proteins which perceive external stimuli and transduce the signal into the cell. Previous reports based on their loss-of-function phenotypes and expression profile support their role in many developmental and stress-responsive pathways. Our study revealed that one member of this family, CRK5, acts as a negative regulator of leaf aging. Enrichment of the CRK5 promoter region in W-box cis-elements demonstrated that WRKY transcription factors control it. We observed significantly enhanced WRKY53 expression in crk5 and reversion of its early-senescence phenotype in the crk5 wrky53 line, suggesting a negative feedback loop between these proteins antagonistically regulating chlorophyll a and b contents. Yeast-two hybrid assay showed further that CRK5 interacts with several proteins involved in response to water deprivation or calcium signaling, while gas exchange analysis revealed a positive effect of CRK5 on water use efficiency. Consistent with that, the crk5 plants showed disturbed foliar temperature, stomatal conductance, transpiration, and increased susceptibility to osmotic stress. These traits were fully or partially reverted to wild-type phenotype in crk5 wrky53 double mutant. Obtained results suggest that WRKY53 and CRK5 are antagonistic regulators of chlorophyll synthesis/degradation, senescence, and stomatal conductance.

The Contribution of PGPR in Salt Stress Tolerance in Crops: Unravelling the Molecular Mechanisms of Cross-Talk between Plant and Bacteria

“…ORS278 in A. thaliana. WRKY50 and ZAT10 were previously indicated by Taki et al [150] as OPDA-specific response genes, and were also found to be related to plant salt stress response [155,156].…”

The cysteine‐rich receptor‐like kinase CRK4 contributes to the different drought stress response between Columbia and Landsberg erecta

“…However, the mechanisms underlying drought tolerance and the molecular pathways involved in drought stress sensing and cellular responses remain largely unknown. RLKs perceive the majority of internal and external stimuli in plants, and CRKs play important roles in plant development, responses to biotic and abiotic stress (including drought stress) (Bourdais et al, 2015; Burdiak et al, 2022; Chen et al, 2004; Hunter et al, 2019; Yeh et al, 2015; Zhao et al, 2022), making them promising candidates for manipulating stress‐response pathways. Here, we present molecular evidence that CRK4 and CRK14, which showed differential expression between Col‐0 and L er ‐0, positively and negatively regulate, respectively, ABA‐mediated stomatal movements and drought stress responses.…”

Deletion of the sugar importer gene OsSWEET1b accelerates sugar starvation-promoted leaf senescence in rice

“…WRKYs positively or negatively regulate leaf senescence depending on their diverse target genes. In Arabidopsis, AtWRKY6, AtWRKY53, AtWRKY55, and AtWRKY71 can directly target and activate the expressions of receptor-like protein kinase genes, senescence-induced receptor-like kinase ( SIRK ) and cysteine-rich receptor-like kinase 5 ( CRK5 ), or SAGs, senescence-associated gene 13 ( SAG13 ), senescence-associated gene 201 ( SAG201 ), and stay-green ( SGR ), to positively influence senescence ( Robatzek and Somssich 2002 ; Zhang et al 2018 ; Wang et al 2020 ; Yu et al 2021 ; Burdiak et al 2022 ). In rice, OsWRKY42 binds to the rice Metallothionein 1d ( OsMT1d ) promoter and represses its expression to promote senescence ( Han et al 2014 ).…”