Figure 2.

PHS induces calcium-dependent phosphorylation of 14-3-3 proteins on a conserved serine residue corresponding to Ser58 of human 14-3-3ζ. (a) In vitro phosphorylation assays were performed in the presence or absence (±) of 25 μM PHS on protein extracts of untreated Arabidopsis cells. Phosphorylated 14-3-3 proteins were detected by immunoblotting using antibodies to phosphorylated Ser58 (pSer58). Immunoblotting with an anti-14-3-3 protein antibody shows equal loading. The results presented are representative of three separate experiments. (b) Arabidopsis cells were treated ±25 μM PHS and ±1 mM LaCl₃ for 2 h. 14-3-3 Immunoprecipitates from cell extracts were immunoblotted with the indicated antibodies. The results presented are representative of three separate experiments