Background
SLK (Ste20-like kinase), also known as STK2 (serine/threonine protein kinase 2) or se20-9, is a member of the serine/threonine kinase subfamily, Ste20. This subfamily is comprised of several mammalian kinases which exhibit sequence similarity to the Saccharomyces cerevisiae serine/threonine kinase Ste20, a protein involved in relaying signals from G protein-coupled receptors to cytosolic MAP kinase cascades. Members of this subfamily include KHS, GLK, YSK1, HPK1, Krs-1, Krs-2, GC kinase, HGK and SLK. SLK is a ubiquitously expressed protein that localizes to the cytoplasm and contains an N-terminal protein kinase domain, a central coiled-coil domain and a C-terminal ATH domain. SLK is activated through cleavage by caspase-3. SLK indirectly associates with microtubules and plays an important role in cellular stress, cell motility, cell death and cytoskeletal dynamics.