Non-receptor tyrosine-protein kinase which plays a role in morphogenesis by regulating the epidermal enclosure of the embryo, independently of its kinase activity (PubMed:15958510). Prevents hyperactivation of the Wnt signaling pathway during endoderm development, probably by preventing hmp-2 nuclear translocation (PubMed:20805471). ATP + L-tyrosyl-[protein] = ADP + H(+) + O-phospho-L-tyrosyl-[protein] Interacts with hmp-2. Localizes to the nucleus during cell division in the early embryo and in seam cells and in the developing germline at the larval stage. Localizes in the cytoplasm and at the cell-cell contacts during embryo enclosure and elongation. Nuclear exclusion during elongation is regulated by integrin alpha subunit pat-3 and beta-catenin hmp-2. Expressed in early embryo and, during later stages of embryogenesis, in epithelial cells, body wall muscle, germline and mature sperm. RNAi-mediated knockdown causes a disruption in the dorsal intercalation and ventral migration of epidermal cells, preventing enclosure and elongation of the embryo. Epidermal cells tend to round up and appear to be defective in adhesion (PubMed:15958510). In addition, causes partial nuclear re-localization of hmp-2 in the embryonic epidermis and the production of supernumerary gut nuclei probably resulting from epithelial cell hyperproliferation (PubMed:20805471). Belongs to the protein kinase superfamily. Tyr protein kinase family. Fes/fps subfamily.