Dinter-Gottlieb G
Proc Natl Acad Sci U S A. 1986 Sep;83(17):6250-4. doi: 10.1073/pnas.83.17.6250.
Group I introns are found in nuclear rRNA genes, mitochondrial mRNA and rRNA genes, and chloroplast tRNA genes. The hallmarks of this intron class are a 16-nucleotide consensus sequence and three sets of complementary sequences. The viroids (circular pathogenic plant RNAs) and the virusoids (plant satellite RNAs) also contain the consensus sequence and the three sets of complementary bases. Pairing of the complementary bases would generate a viroid structure resembling a group I intron, which might be stabilized in vivo through interactions with proteins. The Tetrahymena self-splicing rRNA intron further has sequences homologous with regions of potato spindle tuber viroid associated with the severity of viroid symptoms.
I类内含子存在于核rRNA基因、线粒体mRNA和rRNA基因以及叶绿体tRNA基因中。这类内含子的标志是一个16个核苷酸的共有序列和三组互补序列。类病毒(环状致病植物RNA)和拟病毒(植物卫星RNA)也含有该共有序列和三组互补碱基。互补碱基的配对会产生一种类似于I类内含子的类病毒结构,这种结构可能在体内通过与蛋白质的相互作用而稳定下来。嗜热四膜虫自我剪接rRNA内含子还具有与马铃薯纺锤块茎类病毒中与类病毒症状严重程度相关区域同源的序列。