ジャーナル: J Struct Biol X / 年: 2020 タイトル: A complex between the Zika virion and the Fab of a broadly cross-reactive neutralizing monoclonal antibody revealed by cryo-EM and single particle analysis at 4.1 Å resolution. 著者: Anu Tyagi / Tofayel Ahmed / Jian Shi / Shashi Bhushan / 要旨: Zika virus (ZIKV) recently emerged as a major public health concern because it can cause fetal microcephaly and neurological disease such as the Guillain-Barré syndrome. A particularly potent class ...Zika virus (ZIKV) recently emerged as a major public health concern because it can cause fetal microcephaly and neurological disease such as the Guillain-Barré syndrome. A particularly potent class of broadly neutralizing antibodies (nAbs) targets a quaternary epitope located at the interface of two envelope proteins monomers, exposed at the surface of the mature virion. This "E-dimer-dependent epitope" (EDE), comprises the fusion loop of one monomer at the tip of domain II of E and a portion of the domains I and III of the adjacent monomer. Since this epitope largely overlaps with the binding site of the precursor membrane protein (prM) during Zika virion maturation, its molecular surface is evolutionary conserved in flaviviruses such as Dengue and Zika viruses, and can elicit antibodies that broadly neutralize various ZIKV strains. Here, we present a cryo-EM reconstruction at 4.1 Å resolution of the virion bound to the antigen binding fragment (Fab) of an antibody that targets this mutationally-constrained quaternary epitope. The Fab incompletely covers the surface of the virion as it does not bind next to its 5-fold icosahedral axes. The structure reveals details of the binding mode of this potent neutralizing class of antibodies and can inform the design of immunogens and vaccines targeting this conserved epitope.
T: Small envelope protein M U: Small envelope protein M V: Small envelope protein M Q: Envelope protein E N: Envelope protein E K: Envelope protein E D: Fab Heavy chain E: Fab light chain R: Fab Heavy chain S: Fab light chain ヘテロ分子
T: Small envelope protein M U: Small envelope protein M V: Small envelope protein M Q: Envelope protein E N: Envelope protein E K: Envelope protein E D: Fab Heavy chain E: Fab light chain R: Fab Heavy chain S: Fab light chain ヘテロ分子
T: Small envelope protein M U: Small envelope protein M V: Small envelope protein M Q: Envelope protein E N: Envelope protein E K: Envelope protein E D: Fab Heavy chain E: Fab light chain R: Fab Heavy chain S: Fab light chain ヘテロ分子
x 5
icosahedral pentamer
1.42 MDa, 50 ポリマー
分子量 (理論値)
分子数
合計 (水以外)
1,416,685
55
ポリマ-
1,414,563
50
非ポリマー
2,122
5
水
0
タイプ
名称
対称操作
数
point symmetry operation
5
4
T: Small envelope protein M U: Small envelope protein M V: Small envelope protein M Q: Envelope protein E N: Envelope protein E K: Envelope protein E D: Fab Heavy chain E: Fab light chain R: Fab Heavy chain S: Fab light chain ヘテロ分子