The protein encoded by this gene belongs to the CDC2-like protein kinase (CLK) family. This protein kinase can interact with and phosphorylate the serine- and arginine-rich (SR) proteins, which are known to play an important role in the formation of spliceosomes, and thus may be involved in the regulation of alternative splicing. Studies in the Israeli sand rat Psammomys obesus suggested that the ubiquitin-like 5 (UBL5/BEACON), a highly conserved ubiquitin-like protein, may interact with and regulate the activity of this kinase. Multiple alternatively spliced transcript variants have been observed, but the full-length natures of which have not yet been determined.CLK4 (CDC Like Kinase 4) is a Protein Coding gene. Among its related pathways are mRNA Splicing - Major Pathway. GO annotations related to this gene include transferase activity, transferring phosphorus-containing groups and protein tyrosine kinase activity. An important paralog of this gene is CLK1.