CLP1 (Cleavage And Polyadenylation Factor I Subunit 1) encodes a member of the Clp1 family. The encoded protein is a multifunctional kinase which is a component of the tRNA splicing endonuclease complex and a component of the pre-mRNA cleavage complex II. This protein is implicated in tRNA, mRNA, and siRNA maturation. Mutations in CLP1 are associated with pontocerebellar hypoplasia type 10 (PCH10). Alternatively splice transcript variants encoding different isoforms have been found for CLP1.