SRSF Protein Kinase 1 (SRPK1)

SRPK1 localizes to the nucleus and the cytoplasm. It is thought to play a role in regulation of both constitutive and alternative splicing by regulating intracellular localization of splicing factors. A second alternatively spliced transcript variant for this gene has been described, but its full length nature has not been determined.The SRPK1 gene was cloned; it encodes a protein of 655 amino acids. SRPK1 is similar to a hypothetical C. elegans kinase, CEHK, and to the fission yeast kinase Dsk1. The association of phosphorylation of SR proteins in vivo with SRPK1 activity in the extracts, together with the fact that SRPK1 was the only major kinase for SR proteins obtained during purification, strongly suggests that SRPK1 is responsible for phosphorylation of SR proteins during the cell cycle in vivo.