encodes at least five large (~1200-1600 residue) proteins, orthologous to human NAV1, NAV2/RAINB1 (OMIM:607026
), and NAV3, and homologous to Drosophila CG10662; UNC-53 proteins are required for anteroposterior guidance of migrating cells, axons, and excretory cell canals; unc-53
mutations affect egg laying, backward locomotion, body size, and male mating; UNC-53 proteins vary in their N-terminal regions but share common C-terminal sequences with a AAA-ATPase domain; the UNC-53 N-terminus physically interacts with ABI-1, suggesting that UNC-53 may function as a scaffold to link the ARP2/3 complex to ABI-1; UNC-53 also interacts both physically and genetically with SEM-5; unc-53
is expressed in those cells requiring it, suggesting that its function is cell-autonomous; overexpression of unc-53
induces excess cellular outgrowth.