Enables ubiquitin-like protein ligase binding activity. Involved in several processes, including definitive erythrocyte differentiation; liver development; and protein ufmylation. Acts upstream of or within positive regulation of transcription by RNA polymerase II. Located in cytoplasm. Is expressed in several structures, including brain; hemolymphoid system gland; liver; retina; and seminiferous cord. Orthologous to human CDK5RAP3 (CDK5 regulatory subunit associated protein 3). [provided by Alliance of Genome Resources, Apr 2022]