Read L K, Wilson K D, Myler P J, Stuart K
Seattle Biomedical Research Institute, WA 98109-1651.
Nucleic Acids Res. 1994 Apr 25;22(8):1489-95. doi: 10.1093/nar/22.8.1489.
RNA editing post-transcriptionally modifies several mRNAs from the maxicircle of kinetoplastid parasites by addition and removal of uridine residues. We report here that maxicircle CR5 transcripts of Trypanosoma brucei are edited in two domains separated by an eight nucleotide sequence that remains unedited. The large 5' domain is edited to a consensus sequence while the smaller 3' domain is edited to multiple final sequences. In all, 205-217 Us are inserted and 13-16 encoded uridines are deleted from the CR5 mRNA, producing a mature transcript 75-80% larger than the unedited transcript. The edited RNAs predict small, highly hydrophobic proteins. The carboxy terminal 15-30% of these predicted proteins have multiple different amino acid sequences as a result of the variable edited 3' mRNA sequence, but these fall into two families of sequence. Limited amino acid sequence and hydrophobicity profile similarities suggest that the protein encoded by edited CR5 mRNA may be a subunit of NADH dehydrogenase.
RNA编辑通过添加和去除尿苷残基，对动质体寄生虫大环中的多个mRNA进行转录后修饰。我们在此报告，布氏锥虫的大环CR5转录本在两个结构域中进行编辑，这两个结构域由一个未编辑的八核苷酸序列分隔。较大的5'结构域被编辑为一个共有序列，而较小的3'结构域被编辑为多个最终序列。总共向CR5 mRNA中插入205 - 217个尿苷，并删除13 - 16个编码的尿苷，产生的成熟转录本比未编辑的转录本大75 - 80%。编辑后的RNA预测会形成小的、高度疏水的蛋白质。由于可变编辑的3' mRNA序列，这些预测蛋白质的羧基末端15 - 30%具有多种不同的氨基酸序列，但这些序列可分为两个序列家族。有限的氨基酸序列和疏水性图谱相似性表明，编辑后的CR5 mRNA编码的蛋白质可能是NADH脱氢酶亚基。
