Mondeali Mozhgan, Mahjoor Mohamad, Khaledi Mansoor, Saghabashi Ahdiyeh, Rostami Seyedeh Faride Alavi, Modarressi Mohammad Hossein
Department of Medical Genetics, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
Cellular and Molecular Research Centre, Qom University of Medical Sciences, Qom, Iran.
Virus Genes. 2025 Jun 26. doi: 10.1007/s11262-025-02168-w.
The global public health is still at risk due to the COVID-19 pandemic, which was caused by SARS-CoV-2. Disease severity varies among patients and is influenced by mutations in the viral genome, particularly within the spike protein's receptor-binding domain (RBD). This study aimed to investigate the association between RBD mutations and disease severity and to shed light on the fundamental molecular mechanisms. Nasopharyngeal and oropharyngeal samples were obtained from 70 COVID-19 patients in Iran, including 35 mild and 35 deceased cases. The RBD region of the spike protein gene underwent amplification through reverse transcription-polymerase chain reaction (RT-PCR) and was subsequently sequenced using Sanger sequencing. The impact of RBD mutations on binding affinity to human ACE2 (hACE2) was assessed by molecular docking analyses. Sequence analysis identified seven nonsynonymous mutations within the RBD region. The N501Y mutation, which was the most prevalent, showed a significant correlation with disease severity. Molecular docking revealed that the N501Y substitution enhanced binding affinity to hACE2 by increasing hydrophobic interactions and altering the interaction patterns of neighboring residues. This study demonstrates that the N501Y mutation has an independent association with increased severity of COVID-19, likely due to its effect on strengthening the RBD-hACE2 interaction. Further studies involving larger cohorts and diverse populations are necessary to confirm these results and to explore their potential implications for disease management and therapeutic strategies.
由于严重急性呼吸综合征冠状病毒2（SARS-CoV-2）引发的2019冠状病毒病（COVID-19）大流行，全球公共卫生仍面临风险。患者的疾病严重程度各不相同，且受病毒基因组突变的影响，尤其是刺突蛋白受体结合域（RBD）内的突变。本研究旨在调查RBD突变与疾病严重程度之间的关联，并阐明其基本分子机制。从伊朗的70例COVID-19患者中采集了鼻咽和口咽样本，其中包括35例轻症患者和35例死亡病例。通过逆转录聚合酶链反应（RT-PCR）对刺突蛋白基因的RBD区域进行扩增，随后使用桑格测序法进行测序。通过分子对接分析评估RBD突变对与人血管紧张素转换酶2（hACE2）结合亲和力的影响。序列分析在RBD区域内鉴定出7个非同义突变。最常见的N501Y突变与疾病严重程度显著相关。分子对接显示，N501Y取代通过增加疏水相互作用和改变相邻残基的相互作用模式，增强了与hACE2的结合亲和力。本研究表明，N501Y突变与COVID-19严重程度增加存在独立关联，这可能是由于其对加强RBD-hACE2相互作用的影响。有必要开展涉及更大队列和不同人群的进一步研究，以证实这些结果，并探索其对疾病管理和治疗策略的潜在影响。
