Involved in negative regulation of viral entry into host cell and response to virus. Acts upstream of or within defense response to virus. Predicted to be located in late endosome membrane and lysosomal membrane. Predicted to be part of protein-containing complex. Predicted to be active in plasma membrane. Is expressed in several structures, including 4-cell stage embryo; brain; genitourinary system; hemolymphoid system; and liver. Orthologous to human IFITM2 (interferon induced transmembrane protein 2). [provided by Alliance of Genome Resources, Apr 2022]