Snurportin1 is a novel nuclear import receptor which contains an N-terminal importin beta binding domain which is essential for its function of a snRNP-specific nuclear import receptor [1]. Snurportin1 interacts with m3G-cap where it enhances the m3G-cap dependent nuclear import of U snRNPs in Xenopus laevis oocytes and digitonin-permeabilized HeLa cells [1].

1: Snurportin1, an m3G-cap-specific nuclear import receptor with a novel domain structure. Huber J, Cronshagen U, Kadokura M, Marshallsay C, Wada T, Sekine M, Luhrmann R; EMBO J. 1998;17:4114-4126. PMID:9670026