Suraweera Chathura D, Hinds Mark G, Kvansakul Marc
Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC 3086, Australia.
Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC 3052, Australia.
Pathogens. 2020 Dec 23;10(1):6. doi: 10.3390/pathogens10010006.
Apoptosis is a form of cellular suicide initiated either via extracellular (extrinsic apoptosis) or intracellular (intrinsic apoptosis) cues. This form of programmed cell death plays a crucial role in development and tissue homeostasis in multicellular organisms and its dysregulation is an underlying cause for many diseases. Intrinsic apoptosis is regulated by members of the evolutionarily conserved B-cell lymphoma-2 (Bcl-2) family, a family that consists of pro- and anti-apoptotic members. Bcl-2 genes have also been assimilated by numerous viruses including pox viruses, in particular the sub-family of chordopoxviridae, a group of viruses known to infect almost all vertebrates. The viral Bcl-2 proteins are virulence factors and aid the evasion of host immune defenses by mimicking the activity of their cellular counterparts. Viral Bcl-2 genes have proved essential for the survival of virus infected cells and structural studies have shown that though they often share very little sequence identity with their cellular counterparts, they have near-identical 3D structures. However, their mechanisms of action are varied. In this review, we examine the structural biology, molecular interactions, and detailed mechanism of action of poxvirus encoded apoptosis inhibitors and how they impact on host-virus interactions to ultimately enable successful infection and propagation of viral infections.
细胞凋亡是一种细胞自杀形式,可通过细胞外(外源性细胞凋亡)或细胞内(内源性细胞凋亡)信号引发。这种程序性细胞死亡形式在多细胞生物的发育和组织稳态中起着至关重要的作用,其失调是许多疾病的根本原因。内源性细胞凋亡受进化上保守的B细胞淋巴瘤2(Bcl-2)家族成员调控,该家族由促凋亡和抗凋亡成员组成。Bcl-2基因也被包括痘病毒在内的多种病毒所同化,特别是脊索痘病毒科亚家族,这是一类已知能感染几乎所有脊椎动物的病毒。病毒Bcl-2蛋白是毒力因子,通过模仿其细胞对应物的活性来帮助逃避宿主免疫防御。事实证明,病毒Bcl-2基因对于病毒感染细胞的存活至关重要,结构研究表明,尽管它们通常与其细胞对应物的序列同一性很低,但它们具有近乎相同的三维结构。然而,它们的作用机制各不相同。在这篇综述中,我们研究了痘病毒编码的凋亡抑制剂的结构生物学、分子相互作用和详细作用机制,以及它们如何影响宿主-病毒相互作用,最终实现病毒感染的成功感染和传播。