ATP + L-tyrosyl-[protein] = ADP + H(+) + O-phospho-L-tyrosyl-[protein] The F-BAR domain is truncated and contains only the FCH region (the coiled-coil region is missing). This protein is synthesized as a Gag-Fps polyprotein. Present in the avian viruses PRCII and Fujinami sarcoma virus (FSV). PRCII is less oncogenic than FSV and has a slightly different v-Fps protein. Belongs to the protein kinase superfamily. Tyr protein kinase family. Fes/fps subfamily.