Arrestin-3 binds c-Jun N-terminal kinase 1 (JNK1) and JNK2 and facilitates the activation of these ubiquitous JNK isoforms in cells via scaffolding

Background: The ability of arrestin-3 to facilitate activation of JNK1 and JNK2 has never been reported. Results: Arrestin-3 binds JNK1α1 and JNK2α2 and promotes their phosphorylation by MKK4 and MKK7 in vitro and in intact cells. Conclusion: Arrestin-3 promotes the activation of ubiquitous JNK1 and JNK2 isoforms. Significance: Arrestin-3 scaffolds MKK4/7-JNK1/2/3 signaling modules and facilitates activation of ubiquitous JNK isoforms. © 2013 by The American Society for Biochemistry and Molecular Biology, Inc.