Félix A. Rey - The coronavirus spike protein: proteolytic activation and conformational changes

Value of the Information & Strength of the Argument

The talk provides a detailed, up-to-date overview of spike protein structure and function, grounded in the speaker’s own cryo-EM data and cited literature. The argumentation is coherent, explaining the sequence of events from receptor binding to membrane fusion, and raises important open questions. The value lies in the visual and structural insights, which are essential for understanding viral entry and vaccine design.

Scientific Rigor, Source Quality, Title Accuracy

The talk is scientifically rigorous, referencing numerous peer-reviewed studies and preprints from reputable labs (e.g., Jason McLellan’s proline mutations, John Briggs’ work). The speaker is an expert in structural virology. The title accurately reflects the content, as the talk indeed focuses on proteolytic activation and conformational changes of the spike protein. No comments were provided, so no public reaction analysis is included.

The title accurately describes the talk's focus on the spike protein's proteolytic activation and conformational changes.

8/10

Talk by a leading structural virologist at an EMBL conference, presenting peer-reviewed cryo-EM structures and discussing ongoing work. Technical content is high and explanations are precise, though it is a conference presentation without formal peer review.

Markers derived by PSI from the transcript: the creator did not define chapters.

• 02:00Introduction to coronaviruses and the spike protein, mentioning 15 years of crystallography attempts on the spike.
• 05:00Description of pre-fusion and post-fusion structures, showing the S1 crown and S2 core.
• 07:00Explanation of the conformational change and the spring-loaded mechanism of S2.
• 10:00Discussion of the double proline mutations used to stabilize the pre-fusion form.
• 12:00Cryo-EM structure of the spike-ACE2 complex, showing open and closed RBD conformations.
• 15:00Questions from the audience: stem region targeting, circulating ACE2, CD147 binding, glycosylation, and neutralizing antibodies.

• Structure of the SARS-CoV-2 spike protein in the prefusion conformation (McLellan et al.) — Mentioned as the source of the double proline mutations that stabilize the prefusion conformation.
• John Briggs' paper on spike conformations — Referred to for the observation of post-fusion forms on virions and RBD open/closed equilibrium.
• Martin Beck's lab work on spike flexibility — Cited as recent reports showing the flexibility of the spike's stalk.

• Wrapp et al., Science (2020) - Cryo-EM structure of the 2019-nCoV spike in the prefusion conformation — Landmark paper on the prefusion spike structure, consistent with the talk's description.
• Walls et al., Cell (2020) - Structure, Function, and Antigenicity of the SARS-CoV-2 Spike Glycoprotein — Provides structural and functional analysis of the spike, supporting the talk's points.

• CD147 as a receptor for SARS-CoV-2 (initial report) — The speaker reports no direct interaction between spike and CD147 in their experiments, contradicting initial claims of CD147 as a receptor.