PAK4 is highly expressed in prostate, testis and colon. PAK4 interacts tightly with GTP-bound but not GDP-bound CDC42 and weakly with RAC. PAK4 phosphorylates and autophosphorylates and also activates the JNK pathway. PAK5, a member of the PAK family of protein kinases contains a CDC42/Rac1 interactive binding (CRIB) motif at the N-terminus and a Ste20-like kinase domain at the C-terminus. PAK5 preferentially binds to CDC42 in the presence of GTP and the CRIB motif is essential for this interaction.PAK6 protein cotranslocates into the nucleus with androgen receptor, which is a steroid hormone-dependent transcription factor that is important for male sexual differentiation and development, in response to androgen. PAK6 was initially identified as an androgen receptor in a yeast two hybrid screen and was found to be highly expressed in testis and prostate tissues. Later experiments have shown it to be activated by MAP kinase kinase 6 and p38 MAP kinase, suggesting that PAK6 may play a role in the cellular response to stress-related signals.
KIAA1142; KIAA1264; p21 (RAC1) activated kinase 7; p21 protein (Cdc42/Rac)-activated kinase 4; p21 protein (Cdc42/Rac)-activated kinase 6; p21 protein (Cdc42/Rac)-activated kinase 7; p21(CDKN1A)-activated kinase 4; p21(CDKN1A)-activated kinase 6; p21(CDKN1A)-activated kinase 7; p21-activated kinase 4; p21-activated kinase 5; p21-activated kinase 6; p21-activated kinase 7; p21CDKN1A-activated kinase 7; PAK-4; PAK-5; PAK-6; PAK-7; PAK4; PAK5; PAK6; PAK7; protein kinase PAK5; protein kinase related to S. cerevisiae STE20, effector for Cdc42Hs; Serine/threonine-protein kinase PAK 4; Serine/threonine-protein kinase PAK 5; Serine/threonine-protein kinase PAK 6; Serine/threonine-protein kinase PAK 7; serine/threonine-protein kinase PAK7