The Functional Consequences of the Novel Ribosomal Pausing Site in SARS-CoV-2 Spike Glycoprotein RNA.
The Functional Consequences of the Novel Ribosomal Pausing Site in SARS-CoV-2 Spike Glycoprotein RNA.
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DOI：
10.3390/ijms22126490
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发表时间：
2021-06-17
影响因子：
5.6
通讯作者：
Redmond TM
中科院分区：
文献类型：
--
作者：
Postnikova OA;Uppal S;Huang W;Kane MA;Villasmil R;Rogozin IB;Poliakov E;Redmond TM
SARS-CoV-2刺突糖蛋白（S蛋白）在氨基酸残基（aa）681-684处获得了独特的新4个氨基酸-PRRA-插入序列，该序列在S蛋白中形成了新的弗林蛋白酶切割位点以及几个新的糖基化位点。我们研究了各种统计特性的-PRRA-插入在RNA水平（CCUCGGCGGGCA）。该序列的核苷酸组成和密码子使用与SARS-CoV-2基因组的其余部分不同。这些特征之一是两个串联的CGG密码子，尽管CGG密码子是SARS-CoV-2基因组中最罕见的密码子。这表明，插入序列可能会导致核糖体暂停作为这些罕见的密码子的结果。由于群体变异，CCU密码子的Nextstrain趋异度量非常大。我们不能排除这种差异可能会影响宿主免疫应答/SARS-CoV-2疫苗的有效性，可能性有待进一步研究。我们的实验研究表明，在所有研究的细胞系中，原始RNA序列“野生型”刺突蛋白的表达水平远低于密码子优化的刺突蛋白。有趣的是，原始刺突序列产生更高滴度的假病毒颗粒和更高水平的感染。进一步的诱变实验表明，这种双重效应插入，包括重叠的翻译暂停和弗林蛋白酶位点的组合，使SARS-CoV-2更容易感染其新的宿主（人）。这强调了核糖体暂停的重要性，以允许蛋白质表达的有效调控，也是共翻译亚结构域折叠。
The SARS-CoV-2 Spike glycoprotein (S protein) acquired a unique new 4 amino acid -PRRA- insertion sequence at amino acid residues (aa) 681–684 that forms a new furin cleavage site in S protein as well as several new glycosylation sites. We studied various statistical properties of the -PRRA- insertion at the RNA level (CCUCGGCGGGCA). The nucleotide composition and codon usage of this sequence are different from the rest of the SARS-CoV-2 genome. One of such features is two tandem CGG codons, although the CGG codon is the rarest codon in the SARS-CoV-2 genome. This suggests that the insertion sequence could cause ribosome pausing as the result of these rare codons. Due to population variants, the Nextstrain divergence measure of the CCU codon is extremely large. We cannot exclude that this divergence might affect host immune responses/effectiveness of SARS-CoV-2 vaccines, possibilities awaiting further investigation. Our experimental studies show that the expression level of original RNA sequence “wildtype” spike protein is much lower than for codon-optimized spike protein in all studied cell lines. Interestingly, the original spike sequence produces a higher titer of pseudoviral particles and a higher level of infection. Further mutagenesis experiments suggest that this dual-effect insert, comprised of a combination of overlapping translation pausing and furin sites, has allowed SARS-CoV-2 to infect its new host (human) more readily. This underlines the importance of ribosome pausing to allow efficient regulation of protein expression and also of cotranslational subdomain folding.
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影响因子：
2.5
作者：
Heasley LR;Sampaio NMV;Argueso JL
通讯作者：
Argueso JL
影响因子：
3.5
作者：
Geraerts M;Willems S;Baekelandt V;Debyser Z;Gijsbers R
通讯作者：
Gijsbers R
影响因子：
4.4
作者：
Eng, Jimmy K.;Fischer, Bernd;MacCoss, Michael J.
通讯作者：
MacCoss, Michael J.
影响因子：
5
作者：
Dutta, Rupam;Buragohain, Lukumoni;Borah, Probodh
通讯作者：
Borah, Probodh
神经元翻译受损是自闭症的假定致病因素。
影响因子：
5.5
作者：
Poliakov E;Koonin EV;Rogozin IB
通讯作者：
Rogozin IB