Mercer Jason, Helenius Ari
ETH Zurich, Institute of Biochemistry, Schafmattstrasse 18, ETH Hönggerberg HPM E6.3 Zurich, Switzerland.
Science. 2008 Apr 25;320(5875):531-5. doi: 10.1126/science.1155164.
Viruses employ many different strategies to enter host cells. Vaccinia virus, a prototype poxvirus, enters cells in a pH-dependent fashion. Live cell imaging showed that fluorescent virus particles associated with and moved along filopodia to the cell body, where they were internalized after inducing the extrusion of large transient membrane blebs. p21-activated kinase 1 (PAK1) was activated by the virus, and the endocytic process had the general characteristics of macropinocytosis. The induction of blebs, the endocytic event, and infection were all critically dependent on the presence of exposed phosphatidylserine in the viral membrane, which suggests that vaccinia virus uses apoptotic mimicry to enter cells.
病毒采用多种不同策略进入宿主细胞。痘苗病毒作为痘病毒的原型，以pH依赖的方式进入细胞。活细胞成像显示，荧光病毒颗粒与丝状伪足相关并沿其移动至细胞体，在诱导大的瞬时膜泡突出后被内化。病毒激活了p21激活激酶1（PAK1），并且内吞过程具有巨胞饮作用的一般特征。膜泡的诱导、内吞事件和感染都严重依赖于病毒膜中暴露的磷脂酰丝氨酸的存在，这表明痘苗病毒利用凋亡模拟来进入细胞。
