May be a SFC-associated serine kinase (splicing factor compartment-associated serine kinase) with a role in intranuclear SR protein (non-snRNP splicing factors containing a serine/arginine-rich domain) trafficking and pre-mRNA processing. ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Activity depends on Ca(2+) concentration. Homodimer. Localized in the brefeldin A- sensitive Golgi compartment, at centrosomes, in the nucleus with a somewhat speckle-like presence, membrane-associated to the endoplasmic reticulum (ER) and the plasma membrane (PM), and more diffusely in the cytoplasm. Found to concentrate in splicing factor compartments (SFCs) within the nucleus of interphase cells. The acylation-negative form may be only cytoplasmic and nuclear. Acylation seems to allow the sequestering to the intracellular membranes. Myristoylation may mediate targeting to the intracellular non-Golgi membranes and palmitoylation may mediate the targeting to the Golgi membranes. Dual acylation is required to stabilize the interaction with Golgi membranes (By similarity). Autophosphorylated on serine residues. Myristoylated. Required for membrane association. Prerequisite for palmitoylation to occur (By similarity). Palmitoylated. Belongs to the protein kinase superfamily. CAMK Ser/Thr protein kinase family.