Ribonuclease P/MRP 30kDa Subunit (RPP30)

Ribonuclease P (RNase P) removes the 5-prime leader sequences from precursor tRNA molecules. RNase P consists of an RNA species (H1 RNA), the POP1 protein, and at least 7 proteins called RPPs. The RPPs have apparent molecular masses of 14 kD (RPP14), 20 kD (RPP20), 25 kD (RPP25), 29 kD (RPP29), 30 kD (RPP30), 38 kD (RPP38), and 40 kD (RPP40). Patients with scleroderma have serum reactive with RNase P, the Th antigen, which is also referred to as the To antigen, and RPP30 and RPP38.

RPP30 is a target for antisera from systemic sclerosis patients. Immunoprecipitation analysis showed that polyclonal antibodies raised against RPP20, RPP30, RPP38, or RPP40 interact with RNase P from HeLa cells.