TRIM21 Protein, Human, Recombinant (E. coli, His)Tripartite motif-containing protein 21, TRIM21, SSA1, Sjoegren syndrome type A antigen (SS-A), RO52, Ro(SS-A), RNF81, RING finger protein 81, E3 ubiquitin-protein ligase TRIM21, 52 kDa Ro protein, 52 kDa ribonucleoprotein autoantigen Ro/SS-A