7RAM

Cryo-EM Structure of the HCMV gHgLgO Trimer Derived from AD169 and TR strains in complex with PDGFRalpha

7RAM の概要

• エントリーDOI: 10.2210/pdb7ram/pdb
• EMDBエントリー: 24369
• 分子名称: Envelope glycoprotein H, Envelope glycoprotein L, Envelope glycoprotein O, ... (4 entities in total)
• 機能のキーワード: viral entry glycoprotein in complex with receptor, viral protein
• 由来する生物種: Human herpesvirus 5 strain AD169; 詳細
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 220881.18

構造登録者

Liu, J.,Vanarsdall, A.L.,Chen, D.,Johnson, D.C.,Jardetzky, T.S. (登録日: 2021-07-02, 公開日: 2022-06-08, 最終更新日: 2024-11-13)

主引用文献

Liu, J.,Vanarsdall, A.,Chen, D.H.,Chin, A.,Johnson, D.,Jardetzky, T.S.
Cryo-Electron Microscopy Structure and Interactions of the Human Cytomegalovirus gHgLgO Trimer with Platelet-Derived Growth Factor Receptor Alpha.
Mbio, 12:e0262521-e0262521, 2021

PubMed Abstract: Human cytomegalovirus (HCMV) is a herpesvirus that produces disease in transplant patients and newborn children. Entry of HCMV into cells relies on gH/gL trimer (gHgLgO) and pentamer (gHgLUL128-131) complexes that bind cellular receptors. Here, we studied the structure and interactions of the HCMV trimer, formed by AD169 strain gH and gL and TR strain gO proteins, with the human platelet-derived growth factor receptor alpha (PDGFRα). Three trimer surfaces make extensive contacts with three PDGFRα N-terminal domains, causing PDGFRα to wrap around gO in a structure similar to a human hand, explaining the high-affinity interaction. gO is among the least conserved HCMV proteins, with 8 distinct genotypes. We observed high conservation of residues mediating gO-gL interactions but more extensive gO variability in the PDGFRα interface. Comparisons between our trimer structure and a previously determined structure composed of different subunit genotypes indicate that gO variability is accommodated by adjustments in the gO-PDGFRα interface. We identified two loops within gO that were disordered and apparently glycosylated, which could be deleted without disrupting PDGFRα binding. We also identified four gO residues that contact PDGFRα, which when mutated produced markedly reduced receptor binding. These residues fall within conserved contact sites of gO with PDGFRα and may represent key targets for anti-trimer neutralizing antibodies and HCMV vaccines. Finally, we observe that gO mutations distant from the gL interaction site impact trimer expression, suggesting that the intrinsic folding or stability of gO can impact the efficiency of trimer assembly. HCMV is a herpesvirus that infects a large percentage of the adult population and causes significant levels of disease in immunocompromised individuals and birth defects in the developing fetus. The virus encodes a complex protein machinery that coordinates infection of different cell types in the body, including a trimer formed of gH, gL, and gO subunits. Here, we studied the interactions of the HCMV trimer with its receptor on cells, the platelet derived growth factor receptor α (PDGFRα), to better understand how HCMV coordinates virus entry into cells. Our results add to our understanding of HCMV strain-specific differences and identify sites on the trimer that represent potential targets for therapeutic antibodies or vaccine development.

PubMed: 34700375
DOI: 10.1128/mBio.02625-21

実験手法

ELECTRON MICROSCOPY (3.43 Å)