Lopez P J, Séraphin B
EMBL, Heidelberg, Germany.
EMBO Rep. 2000 Oct;1(4):334-9. doi: 10.1093/embo-reports/kvd065.
Pre-mRNA splicing has to be coordinated with other processes occurring in the nucleus including transcription, mRNA 3' end formation and mRNA export. To analyze the relationship between transcription and splicing, we constructed a network of nested introns. Introns were inserted in the 5' splice site and/or branchpoint of a synthetic yeast intron interrupting a reporter gene. The inserted introns mask the recipient intron from the cellular machinery until they are removed by splicing. Production of functional mRNA from these constructs therefore requires recognition of a spliced RNA as a splicing substrate. We show that recurrent splicing occurs in a sequential and ordered fashion in vivo. Thus, in Saccharomyces cerevisiae, intron recognition and pre-spliceosome assembly is not tightly coupled to transcription.
前体mRNA剪接必须与细胞核中发生的其他过程协调进行，包括转录、mRNA 3' 末端形成和mRNA输出。为了分析转录与剪接之间的关系，我们构建了一个嵌套内含子网络。将内含子插入到一个中断报告基因的合成酵母内含子的5' 剪接位点和/或分支点。插入的内含子会将受体内含子屏蔽起来，使其无法被细胞机制识别，直到它们通过剪接被去除。因此，从这些构建体产生功能性mRNA需要将剪接后的RNA识别为剪接底物。我们表明，重复剪接在体内以连续且有序的方式发生。因此，在酿酒酵母中，内含子识别和剪接体前体组装与转录并非紧密耦合。
