Figure 1.

EphA4 mutants, their tyrosine phosphorylation state, and their kinase activity. Xenopus embryos were left uninjected or injected with RNA encoding wild type (WT) or various mutant EphA4 receptors. (A) Schematic representations of the kinase dead (KD, K653R), juxtamembrane tyrosine (Y596/602F), SAM domain deletion (ΔSAM), Y928F, and Y928E mutants are depicted. Embryos were harvested at stage 9, whole embryo lysates were immunoprecipitated with anti-EphA4 antibody and analyzed by Western blot analysis with antiphosphotyrosine antibodies (B) or in vitro kinase assays (C) were performed. SP, signal peptide; GD, globular ligand binding domain; TM, transmembrane domain; JM, juxtamembrane region; SAM, sterile alpha motif; PDZ, postsynaptic density protein, discs large, zona occludens binding motif.