Phospho-Proteomics Identifies D-Group MAP Kinases as Substrates of the <i>Arabidopsis</i> Tyrosine Phosphatase RLPH2.

ABSTRACT: Despite being one of the few bona fide plant tyrosine phosphatases, the Arabidopsis thaliana Rhizobiales-like phosphatase 2 (RLPH2) has no known substrates. Utilizing phospho-proteomics, we identified the activation loop phospho-tyrosine of several A. thaliana D-group mitogen-activated protein kinases (MPKs) as potential RLPH2 substrates. All Arabidopsis D-group MPKs possess a TDY activation loop phosphorylation motif, whereas other MPKs (Groups A, B, and C) contain a TEY motif. Our findings reveal that RLPH2 has a strong preference for aspartate (D) in the TXY motif, providing specificity for RLPH2 to exclusively target and dephosphorylate the D-group MPKs. Additionally, D-group MPKs contain a unique activation loop insertion that conforms to a protein phosphat

SUBMITTER: Labandera AM 

PROVIDER: S-EPMC12817480 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature