This entry contains proteins involved in the first step of pre-mRNA splicing to remove introns. Splicing is performed by the spliceosome, which is a complex of snRNAs U1, U2, U4, U5, and U6 and proteins such as pre-mRNA-processing factor 19 (Prp19). The yeast protein Cwc2 contains motifs known to bind RNA, a zinc finger and an RNA recognition motif. Because mutations in the gene are lethal and lead to accumulation of pre-mRNA, and reduced levels of U1, U4, U5 and U6 snRNAs and U4/U6 snRNA complex levels, Cwc2 has been proposed to link the Prp19 complex to the spliceosome during pre-mRNA splicing []. Because Cwc2 is at the spliceosome catalytic centre, it induces an active conformation of the spliceosome's catalytic RNA elements []. Cwc2 is a component of the CWC complex []. The human homologue, known as RBM22 [], also translocates the protein SLU7 from the nucleus to the cytoplasm or vice versa in the case of the calcium-binding protein PDCD6 [].Also included in this entry is the pre-mRNA-splicing factor Slt11 (also known as Ecm2) [].
