Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA-dependent RNA polymerase (RdRp) has been identified to be a mutation hot spot, with the P323L mutation being commonly observed in viral genomes isolated from North America. RdRp forms a complex with nonstructural proteins nsp7 and nsp8 to form the minimal replication/transcription machinery required for genome replication. As mutations in RdRp may affect formation of the RdRp–nsp7–nsp8 supercomplex, we analyzed viral genomes to identify mutations in nsp7 and nsp8 protein sequences. Based on in silico analysis of predicted structures of the supercomplex comprising of native and mutated proteins, we demonstrate that specific mutations in nsp7 and nsp8 proteins may have a role in stabilization of the replication/transcription complex.

中文翻译：

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SARS-CoV-2 nsp7 和 nsp8 蛋白的突变及其对复制/转录复杂结构的预测影响

严重急性呼吸综合征冠状病毒 2 (SARS-CoV-2) RNA 依赖性 RNA 聚合酶 (RdRp) 已被确定为突变热点，在从北美分离的病毒基因组中通常观察到 P323L 突变。RdRp 与非结构蛋白 nsp7 和 nsp8 形成复合物，形成基因组复制所需的最小复制/转录机制。由于 RdRp 的突变可能影响 RdRp-nsp7-nsp8 超复合物的形成，我们分析了病毒基因组以鉴定 nsp7 和 nsp8 蛋白序列中的突变。基于对包含天然和突变蛋白质的超复合物的预测结构的计算机分析，我们证明了 nsp7 和 nsp8 蛋白质中的特定突变可能在复制/转录复合物的稳定中起作用。