Exosome Component 10 (EXOSC10)

Antinucleolar antibodies are found in patients with scleroderma or polymyositis or in patients with overlap of these 2 syndromes. The 2 most prominent proteins in this PMSCL autoantigen complex, PMSCL1 and PMSCL2, are detected as 75- and 100-kD molecules, respectively. The deduced 860-amino acid protein contains 2 potential N-glycosylation sites and multiple potential phosphorylation sites. Northern blot analysis revealed expression of a 2.7-kb transcript. Immunoblot analysis confirmed the identity of native and recombinant 100-kD PMSCL2 proteins.

Sequence analysis predicted that the 885-amino acid protein contains a stretch of amino acids also found in serine/threonine kinases. Epitope mapping indicated a major epitope is localized between residues 153 and 324.