8B7D image
Entry Detail
PDB ID:
8B7D
Title:
Luminal domain of TMEM106B
Biological Source:
Source Organism:
Host Organism:
PDB Version:
Deposition Date:
2022-09-29
Release Date:
2023-07-19
Method Details:
Experimental Method:
Resolution:
2.59 Å
R-Value Free:
0.24
R-Value Work:
0.23
R-Value Observed:
0.23
Space Group:
P 41 21 2
Macromolecular Entities
Polymer Type:polypeptide(L)
Description:Transmembrane protein 106B
Chain IDs:A
Chain Length:199
Number of Molecules:1
Biological Source:Homo sapiens
Ligand Molecules
Primary Citation

Abstact

SARS-CoV-2 is associated with broad tissue tropism, a characteristic often determined by the availability of entry receptors on host cells. Here, we show that TMEM106B, a lysosomal transmembrane protein, can serve as an alternative receptor for SARS-CoV-2 entry into angiotensin-converting enzyme 2 (ACE2)-negative cells. Spike substitution E484D increased TMEM106B binding, thereby enhancing TMEM106B-mediated entry. TMEM106B-specific monoclonal antibodies blocked SARS-CoV-2 infection, demonstrating a role of TMEM106B in viral entry. Using X-ray crystallography, cryogenic electron microscopy (cryo-EM), and hydrogen-deuterium exchange mass spectrometry (HDX-MS), we show that the luminal domain (LD) of TMEM106B engages the receptor-binding motif of SARS-CoV-2 spike. Finally, we show that TMEM106B promotes spike-mediated syncytium formation, suggesting a role of TMEM106B in viral fusion. Together, our findings identify an ACE2-independent SARS-CoV-2 infection mechanism that involves cooperative interactions with the receptors heparan sulfate and TMEM106B.

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Primary Citation of related structures