The function of ENSG00000196711 (ALKAL1, ALK and LTK ligand 1) is as follows. Cytokine that acts as a physiological ligand for receptor tyrosine kinase LTK, leading to its activation (PubMed:25331893, PubMed:26418745, PubMed:26630010, PubMed:34646012, PubMed:34819673). Monomeric ALKAL1 binds to LTK, leading to LTK homodimerization and activation (PubMed:34646012, PubMed:34819673). In contrast to ALKAL2, does not act as a potent physiological ligand for ALK (PubMed:26418745, PubMed:34646012). {ECO:0000269|PubMed:25331893, ECO:0000269|PubMed:26418745, ECO:0000269|PubMed:26630010, ECO:0000269|PubMed:34646012, ECO:0000269|PubMed:34819673}.