Tyrosine-protein kinase which plays a role in RNA-mediated gene silencing by mediating import of double-stranded RNA (dsRNA) into cells. Not required for import of ingested dsRNA into intestinal cells but involved in subsequent export from intestinal cells to internal tissues. ATP + L-tyrosyl-[protein] = ADP + H(+) + O-phospho-L-tyrosyl-[protein] Displays diffuse localization in cytoplasm and cytoplasmic foci, and also in a punctate pattern. Ubiquitously present in all tissues tested. Expressed in the somatic cells of gut, pharynx, body wall muscle, neurons, skin and excretory canal cells. Expressed throughout all developmental stages. The kinase domain is required for import of dsRNA into cells. Defective in transport of silencing RNAs but not defective in execution of RNAi. Marginal enhancement of cell-autonomous RNAi. Mildly defective in silencing the intestine-expressed gene, act-5. Belongs to the protein kinase superfamily. Tyr protein kinase family. SYK/ZAP-70 subfamily.