May be specifically involved in cell-cell interactions regulating cell fusions that generate the hypodermis during postembryonic development. It has a role in the development of the HYP7 hypodermal syncytium. ATP + L-tyrosyl-[protein] = ADP + H(+) + O-phospho-L-tyrosyl-[protein] Hypodermal cells. Expressed during hypodermal development. Belongs to the protein kinase superfamily. Tyr protein kinase family.