Unknown

Dataset Information

0

Direct Visualization of the Conformational Dynamics of Single Influenza Hemagglutinin Trimers.


ABSTRACT: Influenza hemagglutinin (HA) is the canonical type I viral envelope glycoprotein and provides a template for the membrane-fusion mechanisms of numerous viruses. The current model of HA-mediated membrane fusion describes a static "spring-loaded" fusion domain (HA2) at neutral pH. Acidic pH triggers a singular irreversible conformational rearrangement in HA2 that fuses viral and cellular membranes. Here, using single-molecule Förster resonance energy transfer (smFRET)-imaging, we directly visualized pH-triggered conformational changes of HA trimers on the viral surface. Our analyses reveal reversible exchange between the pre-fusion and two intermediate conformations of HA2. Acidification of pH and receptor binding shifts the dynamic equilibrium of HA2 in favor of forward progression along the membrane-fusion reaction coordinate. Interaction with the target membrane promotes irreversible transition of HA2 to the post-fusion state. The reversibility of HA2 conformation may protect against transition to the post-fusion state prior to arrival at the target membrane.

SUBMITTER: Das DK 

PROVIDER: S-EPMC6086748 | biostudies-literature |

REPOSITORIES: biostudies-literature

Similar Datasets

| S-EPMC4304640 | biostudies-literature
| S-EPMC7354568 | biostudies-literature
| S-EPMC6177327 | biostudies-literature
| S-EPMC2884258 | biostudies-literature
| S-EPMC9204493 | biostudies-literature
| S-EPMC7508890 | biostudies-literature
| S-EPMC3893665 | biostudies-literature
| S-EPMC155089 | biostudies-literature
| S-EPMC1302762 | biostudies-literature
| S-EPMC1479073 | biostudies-literature