Zhu Yanlei, Alvarez Flavio, Wolff Nicolas, Mechaly Ariel, Brûlé Sébastien, Neitthoffer Benoit, Etienne-Manneville Sandrine, Haouz Ahmed, Boëda Batiste, Caillet-Saguy Célia
Channel Receptors Unit, CNRS, UMR 3571, Institut Pasteur, Université de Paris, Paris, France.
Crystallography Platform-C2RT, CNRS, UMR 3528, Institut Pasteur, Université de Paris, Paris, France.
Front Microbiol. 2022 Feb 23;13:829094. doi: 10.3389/fmicb.2022.829094. eCollection 2022.
The C-terminus of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) protein E contains a PBM (PDZ-binding motif) targeting PDZ (PSD-95/Dlg/ZO-1) domains, which is identical to the PBM of SARS-CoV. The latter is involved in the pathogenicity of the virus. Recently, we identified 10 human PDZ-containing proteins showing significant interactions with SARS-CoV-2 protein E PBM. We selected several of them involved in cellular junctions and cell polarity (TJP1, PARD3, MLLT4, and LNX2) and MPP5/PALS1 previously shown to interact with SARS-CoV E PBM. Targeting cellular junctions and polarity components is a common strategy by viruses to hijack cell machinery to their advantage. In this study, we showed that these host PDZ domains TJP1, PARD3, MLLT4, LNX2, and MPP5/PALS1 interact in a PBM-dependent manner and colocalize with the full-length E protein , sequestrating the PDZ domains to the Golgi compartment. We solved three crystal structures of complexes between human LNX2, MLLT4, and MPP5 PDZs and SARS-CoV-2 E PBM highlighting its binding preferences for several cellular targets. Finally, we showed different affinities for the PDZ domains with the original SARS-CoV-2 C-terminal sequence containing the PBM and the one of the beta variant that contains a mutation close to the PBM. The acquired mutations in the E protein localized near the PBM might have important effects both on the structure and the ion-channel activity of the E protein and on the host machinery targeted by the variants during the infection.
严重急性呼吸综合征冠状病毒2（SARS-CoV-2）蛋白E的C末端包含一个靶向PDZ（PSD-95/Dlg/ZO-1）结构域的PBM（PDZ结合基序），该基序与SARS-CoV的PBM相同。后者与病毒的致病性有关。最近，我们鉴定出10种含人类PDZ的蛋白与SARS-CoV-2蛋白E的PBM有显著相互作用。我们选择了其中几种参与细胞连接和细胞极性的蛋白（TJP1、PARD3、MLLT4和LNX2）以及先前显示与SARS-CoV E PBM相互作用的MPP5/PALS1。靶向细胞连接和极性成分是病毒劫持细胞机制以使其受益的常见策略。在本研究中，我们表明这些宿主PDZ结构域TJP1、PARD3、MLLT4、LNX2和MPP5/PALS1以PBM依赖的方式相互作用，并与全长E蛋白共定位，将PDZ结构域隔离到高尔基体区室。我们解析了人类LNX2、MLLT4和MPP5的PDZ与SARS-CoV-2 E PBM之间复合物的三种晶体结构，突出了其对几种细胞靶点的结合偏好。最后，我们展示了PDZ结构域对含有PBM的原始SARS-CoV-2 C末端序列以及含有靠近PBM处突变的β变体序列的不同亲和力。E蛋白中靠近PBM处获得的突变可能对E蛋白的结构和离子通道活性以及感染期间变体靶向的宿主机制都有重要影响。
