CARK1 phosphorylates subfamily III members of ABA receptors.

ABSTRACT: Abscisic acid (ABA) plays a vital role in responses to abiotic stresses that allow plants to cope with environmental challenges. In this study, we analyzed ABA receptors of subfamily III as the potential targets of Cytosolic ABA Receptor Kinase 1 (CARK1). We previously found that CARK1 phosphorylated the subfamily III member RCAR11 at a distinct threonine residue (T78). Our study now shows the physical interaction of CARK1 with the receptors RCAR12/13/14 in vitro and in vivo. The catalytically inactive form CARK1-N204A did not interact with the receptors. Phosphorylation of these ABA receptors in vitro occurred at a serine/threonine amino acid residue corresponding to T78 in RCAR11, which is located in the loop of β3 within a conserved site. Further analysis revealed that the phosphorylati

SUBMITTER: Li X 

PROVIDER: S-EPMC6322571 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature