A simple model to explain evolutionary trends of eukaryotic gene architecture and expression: how competition between splicing and cleavage/polyadenylation factors may affect gene expression and splice-site recognition in eukaryotes.
A simple model to explain evolutionary trends of eukaryotic gene architecture and expression: how competition between splicing and cleavage/polyadenylation factors may affect gene expression and splice-site recognition in eukaryotes.
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DOI：
10.1002/bies.201200127
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发表时间：
2013-06
期刊：
影响因子：
--
通讯作者：
Lynch M
中科院分区：
文献类型：
--
作者：
Catania F;Lynch M
蛋白质编码基因中内含子的数量和大小存在着巨大的系统发育差异。虽然在确定这种模式时已考虑到种群遗传环境的潜在作用，但细胞内环境的影响实际上仍未得到探索。根据对剪接共转录过程与mRNA 3 '端形成之间相互作用的观察，作者提出了一个剪接位点识别的机制模型，挑战了普遍接受的内含子和外显子定义模型。在该模型下，与3 ‘端加工因子竞争进入内含子结合位点的剪接因子同时有利于3 ’端加工因子在mrna前尾部的招募。这一假设为内含子介导的基因表达增强以及内含子长度与基因表达水平之间的负相关等观察结果提供了新的线索。
Enormous phylogenetic variation exists in the number and sizes of introns in protein-coding genes. Although some consideration has been given to the underlying role of the population-genetic environment in defining such patterns, the influence of the intracellular environment remains virtually unexplored. Drawing from observations on interactions between co-transcriptional processes involved in splicing and mRNA 3′-end formation, a mechanistic model is proposed for splice-site recognition that challenges the commonly accepted intron- and exon-definition models. Under the suggested model, splicing factors that outcompete 3′-end processing factors for access to intronic binding sites concurrently favor the recruitment of 3′-end processing factors at the pre-mRNA tail. This hypothesis sheds new light on observations such as the intron-mediated enhancement of gene expression and the negative correlation between intron length and levels of gene expression.