Predicted to enable RNA binding activity. Acts upstream of or within regulation of retina development in camera-type eye and visual behavior. Predicted to be located in nucleus. Predicted to be part of U2 snRNP and precatalytic spliceosome. Is expressed in head. Human ortholog(s) of this gene implicated in Nager acrofacial dysostosis; cervical cancer; and hepatocellular carcinoma. Orthologous to human SF3B4 (splicing factor 3b subunit 4).