Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 1st Street SW, Rochester, MN, 55905, USA.
Center for Basic Research in Digestive Diseases, Division of Gastroenterology & Hepatology, Mayo Clinic, 200 1st Street SW, Rochester, MN, 55905, USA.
Nat Commun. 2020 Feb 26;11(1):1048. doi: 10.1038/s41467-020-14727-w.
The membrane deforming dynamin family members MxA and MxB are large GTPases that convey resistance to a variety of infectious viruses. During viral infection, Mx proteins are known to show markedly increased expression via an interferon-responsive promoter to associate with nuclear pores. In this study we report that MxB is an inner mitochondrial membrane GTPase that plays an important role in the morphology and function of this organelle. Expression of mutant MxB or siRNA knockdown of MxB leads to fragmented mitochondria with disrupted inner membranes that are unable to maintain a proton gradient, while expelling their nucleoid-based genome into the cytoplasm. These findings implicate a dynamin family member in mitochondrial-based changes frequently observed during an interferon-based, anti-viral response.
膜变形动力蛋白家族成员 MxA 和 MxB 是两种大型 GTP 酶，它们能够抵抗多种感染性病毒。在病毒感染过程中，已知 Mx 蛋白通过干扰素反应启动子表现出明显增加的表达，以与核孔结合。在这项研究中，我们报告 MxB 是一种线粒体内膜 GTP 酶，它在细胞器的形态和功能中起着重要作用。表达突变型 MxB 或 siRNA 敲低 MxB 会导致线粒体片段化，内膜破裂，无法维持质子梯度，同时将基于核仁的基因组排出到细胞质中。这些发现表明，在基于干扰素的抗病毒反应中，经常观察到一种动力蛋白家族成员参与线粒体的变化。
