Protein kinase that recognizes phosphorylation sites in which the surrounding peptides have an alpha-helical conformation (PubMed:10021370). Regulates cardiac development and cardiomyocyte differentiation by negatively regulating Wnt/beta-catenin signaling (PubMed:29888752). ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Expressed in developing cardiac tissue and cardiomyocytes (at protein level). Detected in cardiac progenitor cells with expression levels increasing as progenitor cells differentiate into cardiomyocytes. Belongs to the protein kinase superfamily. Alpha-type protein kinase family. ALPK subfamily. Truncated N-terminus. Aberrant splicing. Truncated N-terminus. Aberrant splicing. Aberrant splicing. Truncated N-terminus.