Retinitis pigmentosa 9 （RP9） is assumed to be a target protein for the PIM1 kinase. The RP9 protein may have some roles in B-cell proliferation in association with PIM1. RP9 can be bound and phosphorylated by the protooncogene PIM1 product， a serine/threonine protein kinase. RP9 localizes in nuclear speckles containing the splicing factors， and has a part in pre-mRNA splicing. RP9 gene mutations result in autosomal dominant retinitis pigmentosa-9.
