52 kD Ro protein; Sjoegren syndrome type A antigen; SS-A; Ro(SS-A); 52 kD ribonucleoprotein autoantigen Ro/SS-A; tripartite motif-containing protein 21; RING finger protein 81 (TRIM21, RNF81, Ro52, SSA1)

Function

• component of a ribonucleoprotein particle composed of a single polypeptide & one of four small RNA molecules (Y-RNA)
• in the free state, Ro binds to a variety of misfolded RNAs including misfolded 5S rRNAs, & is thought to act as some sort of quality control mechanism
• Y RNA appears to function as a repressor of Ro

Structure

• belongs to the TRIM/RBCC family
• contains 1 B box-type Zn+2 finger
• contains 1 B30.2/SPRY domain
• contains 1 RING-type Zn+2 finger

Compartment

cytoplasm. nucleus

Expression

• present in all mammalian cells studied
• tissue specific differences in RO/SSA proteins have been identified

Pathology

• sera from patients with systemic lupus erythematosus (SLE) or primary Sjoegren syndrome often contain antibodies that react with normal cellular RO protein as if this antigen was foreign

More general terms

• ribonucleoprotein
• DNA-binding protein
• RNA-binding protein
• antigen
• ring finger protein
• phosphoprotein

Additional terms

• Sjogren syndrome type A antigen (SSA/Ro)
• Sjogren's syndrome (autoimmune epitheliitis)
• SSA/Ro Ab in serum

Database

• UniProt: http://www.uniprot.org/uniprot/P19474.html
• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=6737
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:6737
• OMIM: https://mirror.omim.org/entry/109092