Roy G, Mercure S, Beuvon F, Perreault J P
Départment de biochimie, Faculté de médecine, Université de Sherbrooke, QC, Canada.
Biochem Cell Biol. 1997;75(6):789-94. doi: 10.1139/o97-065.
Circular RNAs reminiscent of viroids and the human hepatitis delta virus have been proposed as possible nonconventional pathogens responsible for Crohn's disease and ulcerative colitis, two inflammatory bowel diseases. Consequently, RNA was extracted from various areas of intestinal tissues from individuals with either Crohn's disease or ulcerative colitis as well as several appropriate control diseases, and analyzed by two-dimensional gel electrophoresis. No circular viroid-like RNAs (< 1500 nucleotides) were detected, confirming a previous report that was limited to the investigation of small RNAs (< 300 nucleotides). However, three small, unusually stable, linear RNAs were shown to be associated to both Crohn's disease and ulcerative colitis tissues: a specific 28S ribosomal RNA cleavage product characterized previously; a 5.8S ribosomal RNA conformer; and a fragment homologous to transcripts from DNA CpG islands. The two last RNAs were detected prior to visible morphological tissue alterations, suggesting that they are produced early during the inflammation and that they have value as molecular diagnostic tools for the inflammatory bowel diseases. The potential cellular mechanisms producing these RNAs and their involvement in inflammatory bowel disease are discussed.
环状RNA让人联想到类病毒和人类丁型肝炎病毒，它们被认为可能是导致克罗恩病和溃疡性结肠炎这两种炎症性肠病的非传统病原体。因此，研究人员从患有克罗恩病或溃疡性结肠炎的个体以及几种合适的对照疾病个体的肠道组织不同区域提取了RNA，并通过二维凝胶电泳进行分析。未检测到环状类病毒样RNA（<1500个核苷酸），这证实了之前一项仅限于小RNA（<300个核苷酸）研究的报告。然而，研究发现三种小的、异常稳定的线性RNA与克罗恩病和溃疡性结肠炎组织均相关：一种先前已鉴定的特定28S核糖体RNA裂解产物；一种5.8S核糖体RNA构象异构体；以及一种与DNA CpG岛转录本同源的片段。后两种RNA在可见的形态学组织改变之前就被检测到，这表明它们在炎症早期产生，并且作为炎症性肠病的分子诊断工具具有价值。本文还讨论了产生这些RNA的潜在细胞机制及其在炎症性肠病中的作用。
