Plays a role in the Trc/fry signaling pathway by promoting trc kinase activity (PubMed:11526084, PubMed:15479641, PubMed:32022690). Plays a key role in maintaining the integrity of polarized cell extensions (arista) during morphogenesis, regulates the actin cytoskeleton (PubMed:11526084). Plays a key role in patterning sensory neuron dendritic fields by promoting avoidance between homologous dendrites as well as by limiting dendritic branching (PubMed:15479641). Together with trc, has a role in regulating microtubule-sliding during neurite outgrowth (PubMed:32022690). Co-expressed with trc in all da neurons in third instar wild-type larvae; axons and dendritic branches. Expression is very low in embryonic and early larval stages, increases to be high from third larval instar to adults. Flies exhibit branched arista laterals, branched bristles and a strong multiple hair cell phenotype that consists of clusters of epidermal hairs and branched hairs. Dendrites of fry and trc mutants display excessive terminal branching. Branched laterals in mutant pupae arista are due to the splitting of individual laterals during elongation and abnormally shaped actin bundles. Belongs to the furry protein family.