Small Nuclear Ribonucleoprotein Polypeptide B (SNRPB)

Small nuclear ribonucleoprotein polypeptides B and B1 is one of several nuclear proteins that are found in common among U1, U2, U4/U6, and U5 small ribonucleoprotein particles (snRNPs). These snRNPs are involved in pre-mRNA splicing, and the encoded protein may also play a role in pre-mRNA splicing or snRNP structure. Autoantibodies from patients with systemic lupus erythematosus frequently recognize epitopes on the encoded protein. Two transcript variants encoding different isoforms (B and B""") have been found for this gene.Patients with the autoimmune disease systemic lupus erythematosus (SLE) have autoantibodies directed against some of the individual snRNP polypeptides. The most common autoantigen is called Sm. N bears Sm epitopes.