The phosphatase JKAP/DUSP22 inhibits T-cell receptor signalling and autoimmunity by inactivating Lck

JNK pathway-associated phosphatase (JKAP) is a dual-specificity phosphatase known to regulate substrates in several signalling cascades. Here, Li et al. demonstrate that JKAP has a key role in negative regulation of proximal T-cell receptor signalling and suppression of T-cell-mediated autoimmunity.