Stress-activated, pro-apoptotic kinase which, following caspase-cleavage, enters the nucleus and induces chromatin condensation followed by internucleosomal DNA fragmentation. Key component of the Hippo signaling pathway which plays a pivotal role in organ size control and tumor suppression by restricting proliferation and promoting apoptosis. The core of this pathway is composed of a kinase cascade wherein stk3/mst2 and stk4/mst1, in complex with its regulatory protein sav1, phosphorylates and activates lats1/2 in complex with its regulatory protein mob1, which in turn phosphorylates and inactivates yap1 oncoprotein and wwtr1/taz. Phosphorylation of yap1 by lats2 inhibits its translocation into the nucleus to regulate cellular genes important for cell proliferation, cell death, and cell migration (By similarity).