7FGF

Cryo-EM structure of CCHFV envelope protein Gc in postfusion conformation

Summary for 7FGF

• Entry DOI: 10.2210/pdb7fgf/pdb
• EMDB information: 31579
• Descriptor: Glycoprotein C (1 entity in total)
• Functional Keywords: cchfv, envelope protein, postfusion, bunyavirus, viral protein
• Biological source: Crimean-Congo hemorrhagic fever virus strain IbAr10200 (CCHFV)
• Total number of polymer chains: 3
• Total formula weight: 197429.13

Authors

Li, N.,Rao, G.,Fu, Y.,Cao, S. (deposition date: 2021-07-26, release date: 2022-03-16, Last modification date: 2024-10-23)

Primary citation

Li, N.,Rao, G.,Li, Z.,Yin, J.,Chong, T.,Tian, K.,Fu, Y.,Cao, S.
Cryo-EM structure of glycoprotein C from Crimean-Congo hemorrhagic fever virus.
Virol Sin, 37:127-137, 2022

PubMed Abstract: Crimean-Congo hemorrhagic fever virus (CCHFV) is a causative agent of serious hemorrhagic diseases in humans with high mortality rates. CCHFV glycoprotein Gc plays critical roles in mediating virus-host membrane fusion and has been studied extensively as an immunogen. However, the molecular mechanisms involved in membrane fusion and Gc-specific antibody-antigen interactions remain unresolved largely because structural information of this glycoprotein is missing. We designed a trimeric protein including most of the ectodomain region of Gc from the prototype CCHFV strain, IbAr10200, which enabled the cryo-electron microscopy structure to be solved at a resolution of 2.8 ​Å. The structure confirms that CCHFV Gc is a class II fusion protein. Unexpectedly, structural comparisons with other solved Gc trimers in the postfusion conformation revealed that CCHFV Gc adopted hybrid architectural features of the fusion loops from hantaviruses and domain III from phenuiviruses, suggesting a complex evolutionary pathway among these bunyaviruses. Antigenic sites on CCHFV Gc that protective neutralizing antibodies target were mapped onto the CCHFV Gc structure, providing valuable information that improved our understanding of potential neutralization mechanisms of various antibodies.

PubMed: 35234630
DOI: 10.1016/j.virs.2022.01.015

Experimental method

ELECTRON MICROSCOPY (2.8 Å)