Ro-60/SS-A Antigen , Recombinant, Human

The SS-A/Ro particle contains a hY RNA (human cytoplasmic RNA) and associated proteins: a 60kD and a 52kD protein. The 52kD protein is not directly bound to the hY RNA but to the 60kD protein. It seems that it is sometimes associated, sometimes not. The Ro antigen is found in the cytoplasm but also in the nucleus. An RNA-binding protein, the Ro 60kD autoantigen, is a major target of the immune response in patients suffering from two systemic rheumatic diseases, systemic lupus erythematosus and Sjogren's syndrome. In lupus patients, anti-Ro antibodies are associated with photosensitive skin lesions and with neonatal lupus, a syndrome in which mothers with anti-Ro antibodies give birth to children with photosensitive skin lesions and a cardiac conduction defect, third degree heart block. In vertebrate cells, the Ro protein binds small RNAs of unknown function known as Y RNAs. Although the cellular function of Ro has long been mysterious, recent studies have implicated Ro in two distinct processes: small RNA quality control and the enhancement of cell survival following exposure to ultraviolet irradiation. Most interestingly, mice lacking the Ro protein develop an autoimmune syndrome that shares some features with systemic lupus erythematosus in patients, suggesting that the normal function of Ro may be important for the prevention of this autoimmune disease.||Recombinant protein corresponding to human SS-A/RO-60 is a single, non-glycosylated, polypeptide chain having a molecular mass of 60kD.||Protein Content:|Protein quantitation was carried out by using a 0.25-2.0mg/ml Bradford assay vs. BSA||Source:|Human, recombinant protein expressed in E. coli.||Purity:|≥90% by (SDS-PAGE)||Endotoxin:|≤0.1ng/ug (IEU/ug) ||Concentration:|~0.5mg/ml||Form:|Supplied as a liquid in 10mM Tris, pH 6.0, 6M Urea, 500mM sodium chloride, 500mM imidazole||Storage and Stability:|May be stored at 4°C for short-term only. Aliquot to avoid repeated freezing and thawing. For long term storage it is recommended to add a carrier protein (0.1% HSA or BSA) Store at -20°C. Aliquots are stable for 6 months after receipt at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.