A two-step mechanism for 5' and 3' splice-site pairing
A two-step mechanism for 5' and 3' splice-site pairing
复制标题
5 和 3 剪接位点配对的两步机制
作者：
M. Chiara;R. Reed
前体信使RNA剪接的一个基本问题是如何在剪接反应中识别和配对5‘和3’剪接位点。有人提出，后生动物pre- mrna中的剪接体组装可以通过3‘剪接位点与下游外显子上的特定序列元件（外显子增强子或5’剪接位点）之间的相互作用启动1。随后发生5‘和3’剪接位点的配对。我们在这里报道，如果3‘反式剪接底物含有这些下游序列元件，位于单独的合成pre-mRNA底物上的5’和3'剪接位点可以有效地进行反式剪接。此外，反式5‘剪接位点的选择可以发生在第二个预剪接体复合物A在3’反式剪接底物上组装之后。因此，我们的数据表明，后生动物的5‘和3’剪接位点配对可以在两个不同的步骤中发生。
A FUNDAMENTAL question in the splicing of precursor messenger RNA is how the 5' and 3' splice sites are recognized and paired during the splicing reaction. It has been proposed that spliceosome assembly in metazoan pre-mRNAs can be initiated through interaction between the 3' splice site and specific sequence elements on the downstream exon (an exonic enhancer or a 5' splice site)1. Pairing of the intronic 5' and 3' splice sites occurs subsequently. We report here that 5' and 3' splice sites located on separate synthetic pre-mRNA substrates can be efficiently trans-spliced if the 3' trans-splicing substrate contains these downstream sequence elements. Moreover, selection of the trans 5' splice site can occur after the second pre-spliceosomal complex A has assembled on the 3' trans-splicing substrate. Thus our data demonstrate that 5' and 3' splice-site pairing in metazoans can occur in two distinct steps.
影响因子：
56.9
作者：
KUO, HC;NASIM, FUH;GRABOWSKI, PJ
通讯作者：
GRABOWSKI, PJ