Fig. 6

DUSP3 targets multiple Tyr residues at the carboxyl-terminus of OCLN. A and B H1299 cells expressing with wild-type OCLN or OCLN mutant (OCLN-Y398/402F) were treated with or without H₂O₂ (1 mM) for 30 min. Wild-type and mutated OCLN proteins were immunoprecipitated and analyzed for their Tyr-phosphorylation levels (A) or were subjected to in vitro DUSP3 phosphatase reactions and the subsequent immunoblot analyses (B). C H1299-OCLN cells or H1299 cells-expressing indicated individual OCLN mutants were treated with or without H₂O₂ (1 mM) for 30 min. Wild type and mutated OCLN proteins were immunoprecipitated and analyzed for their Tyr-phosphorylation levels. D and E H1299-OCLN, OCLN (Y315F), and OCLN (Y287/315/325/443F; named 4YF) cells were treated with or without H₂O₂ (1 mM) for 30 min. Wild-type and mutated OCLN proteins were immunoprecipitated and analyzed for their Tyr-phosphorylation levels (D) or were subjected to in vitro DUSP3 phosphatase reactions (E). F Affinity purified Flag-OCLN, OCLN-4YF, and OCLN (Y398/402F) proteins were subjected to in vitro FAK phosphorylation