Smith H C, Kuo S R, Backus J W, Harris S G, Sparks C E, Sparks J D
Department of Pathology and Laboratory Medicine, University of Rochester, NY 14642.
Proc Natl Acad Sci U S A. 1991 Feb 15;88(4):1489-93. doi: 10.1073/pnas.88.4.1489.
Specific apolipoprotein B (apoB) mRNA editing can be performed in vitro on apoB RNA substrates. Native gels and glycerol gradient sedimentation have been used to determine the physical properties of the in vitro editing activity in rat liver cytosolic S100 extracts. ApoB RNA substrates were progressively assembled as 27S complexes for 3 hr with similar kinetics as seen for the accumulation of edited RNA. Assembly was not observed on RNAs from apoB deletion constructs that did not support editing. The 27S complex contained both edited and unedited RNA sequences. Inhibition of 27S complex assembly by vanadyl-ribonucleoside complexes was accompanied by inhibition of editing. Based on these data, we propose that the 27S complex is the in vitro "editosome," A "mooring sequence" model for RNA recognition and editosome assembly has been proposed involving RNA sequences flanking the edited nucleotide.
特定的载脂蛋白B（apoB）mRNA编辑可在体外对apoB RNA底物进行。天然凝胶和甘油梯度沉降已被用于确定大鼠肝脏胞质S100提取物中体外编辑活性的物理性质。apoB RNA底物在3小时内逐渐组装成27S复合物，其动力学与编辑RNA积累时观察到的相似。在不支持编辑的apoB缺失构建体的RNA上未观察到组装。27S复合物包含编辑和未编辑的RNA序列。钒核糖核苷复合物对27S复合物组装的抑制伴随着编辑的抑制。基于这些数据，我们提出27S复合物是体外“编辑体”。已经提出了一种用于RNA识别和编辑体组装的“系泊序列”模型，该模型涉及编辑核苷酸侧翼的RNA序列。
