An autoinhibitory intramolecular interaction proof-reads RNA recognition by the essential splicing factor U2AF2
An autoinhibitory intramolecular interaction proof-reads RNA recognition by the essential splicing factor U2AF2
复制标题
DOI：
10.1073/pnas.1913483117
复制
发表时间：
2020-03-31
影响因子：
11.1
通讯作者：
Sattler, Michael
中科院分区：
文献类型：
--
作者：
Kang, Hyun-Seo;Sanchez-Rico, Carolina;Sattler, Michael
RNA结合蛋白（RBP）识别人类转录物中的顺式调控RNA基序对于基因调控是必不可少的。决定RBP特异性的分子特征通常知之甚少。在这里，我们将NMR结构生物学与高通量iCLIP方法相结合，以确定U2 AF 2 RNA识别的调控机制。我们发现，连接U2 AF 2的两个RNA识别基序（RRM）结构域的内在无序连接区介导了自抑制分子内相互作用，以减少与弱Py-tract RNA的非生产性结合。这种校正有利于U2 AF 2在更强的Py-tracts上的结合，这是在剪接体组装的早期阶段定义3'剪接位点所需的。削弱接头自抑制的突变增强了对弱Py-tracts的亲和力，导致U2 AF 2沿着mRNA混杂结合并影响剪接保真度。我们的研究结果强调了内在无序的连接子调节多结构域RBP的RNA相互作用的重要作用。
The recognition of cis-regulatory RNA motifs in human transcripts by RNA binding proteins (RBPs) is essential for gene regulation. The molecular features that determine RBP specificity are often poorly understood. Here, we combined NMR structural biology with high-throughput iCLIP approaches to identify a regulatory mechanism for U2AF2 RNA recognition. We found that the intrinsically disordered linker region connecting the two RNA recognition motif (RRM) domains of U2AF2 mediates autoinhibitory intramolecular interactions to reduce nonproductive binding to weak Py-tract RNAs. This proofreading favors binding of U2AF2 at stronger Py-tracts, as required to define 3' splice sites at early stages of spliceosome assembly. Mutations that impair the linker autoinhibition enhance the affinity for weak Py-tracts result in promiscuous binding of U2AF2 along mRNAs and impact on splicing fidelity. Our findings highlight an important role of intrinsically disordered linkers to modulate RNA interactions of multidomain RBPs.