NCBP3 and NCBP1 form an alternative cap-binding complex in higher eukaryotes. NCBP3 binds mRNA, associates with components of the mRNA processing machinery and contributes to polyA RNA export [1].

1: mRNA export through an additional cap-binding complex consisting of NCBP1 and NCBP3. Gebhardt A, Habjan M, Benda C, Meiler A, Haas DA, Hein MY, Mann A, Mann M, Habermann B, Pichlmair A; Nat Commun. 2015;6:8192. PMID:26382858