Serine/Threonine Kinase 33 (STK33)

STK33 contains a conserved serine/threonine kinase catalytic domain and an ATP-binding domain. Phylogenetic analysis suggested that STK33 belongs to the CAMK group of serine/threonine kinases; however, STK33 does not have a calcium/calmodulin-binding domain or a C-terminal regulatory tail. STK33 shares 37% amino acid identity with CAMK1 and 28% identity with myosin light chain kinase.Neither alternate transcript codes for a complete kinase domain.STK33 expression at high levels in testis and fetal lung and heart; at intermediate levels in pituitary gland, kidney, interventricular septum, pancreas, all heart tissues, trachea, thyroid gland, and uterus; and at low levels in several other tissues. No expression was detected in any nervous system tissues examined.