PSK2 also known as TAO1, MAP3K16, TAOK1 is a member of the Ser/Thr protein kinase family and belongs to the GCK-like class of STE20-like kinases. PSK2 plays a crucial role in cellular signaling pathways, particularly in regulating the p38 MAP kinase pathway. This pathway is vital for various cellular processes, including stress responses, inflammation, and apoptosis. PSK2 is predominantly expressed in testis, with lower expression levels found in placenta, colon, brain, and skeletal muscle, and localizes in cytoplasm. PSK2 functions by phosphorylating MEK-3, which subsequently activates p38 MAP kinase pathway, thereby influencing cell survival and differentiation. PSK2 can activate JNK, leading to JNK-dependent morphological changes that promote apoptosis. Upon activation of caspases, PSK2 is cleaved by caspase-3, which further underscores PSK2′s role in programmed cell death.