Predicted to be involved in mRNA 5'-splice site recognition. Predicted to act upstream of or within RNA splicing and mRNA processing. Predicted to be located in nucleus. Predicted to be part of U1 snRNP; U2-type prespliceosome; and commitment complex. Orthologous to human PRPF39 (pre-mRNA processing factor 39). [provided by Alliance of Genome Resources, Apr 2022]