Gold H A, Topper J N, Clayton D A, Craft J
Department of Medicine, Yale University School of Medicine, New Haven, CT 06511.
Science. 1989 Sep 22;245(4924):1377-80. doi: 10.1126/science.2476849.
Sera from patients with autoimmune diseases often contain antibodies that bind ribonucleoproteins (RNPs). Sera from 30 such patients were found to immunoprecipitate ribonuclease P (RNase P), an RNP enzyme required to process the 5' termini of transfer RNA transcripts in nuclei and mitochondria of eukaryotic cells. All 30 sera also immunoprecipitated the nucleolar Th RNP, indicating that the two RNPs are structurally related. Nucleotide sequence analysis of the Th RNP revealed it was identical to the RNA component of the mitochondrial RNA processing enzyme known as RNase MRP. Antibodies that immunoprecipitated the Th RNP selectively depleted murine and human cell extracts of RNase MRP activity, indicating that the Th and RNase MRP RNPs are identical. Since RNase P and RNase MRP are not associated with each other during biochemical purification, we suggest that these two RNA processing enzymes share a common autoantigenic polypeptide.
自身免疫性疾病患者的血清中常常含有能与核糖核蛋白（RNP）结合的抗体。研究发现，30例此类患者的血清能免疫沉淀核糖核酸酶P（RNase P），这是一种RNP酶，在真核细胞的细胞核和线粒体中加工转运RNA转录本的5'末端时发挥作用。所有30份血清还能免疫沉淀核仁Th RNP，这表明这两种RNP在结构上相关。对Th RNP的核苷酸序列分析表明，它与被称为RNase MRP的线粒体RNA加工酶的RNA成分相同。能免疫沉淀Th RNP的抗体选择性地耗尽了小鼠和人类细胞提取物中的RNase MRP活性，这表明Th和RNase MRP RNPs是相同的。由于在生化纯化过程中RNase P和RNase MRP彼此不相关，我们认为这两种RNA加工酶共享一种共同的自身抗原性多肽。
