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Related Experiment Video

Updated: Jul 10, 2026

Generation and Assembly of Virus-Specific Nucleocapsids of the Respiratory Syncytial Virus

Generation and Assembly of Virus-Specific Nucleocapsids of the Respiratory Syncytial Virus

Published on: July 27, 2021

Residue conservation in viral capsid assembly.

Ranjit P Bahadur¹, Joël Janin

¹Yeast Structural Genomics, IBBMC Université Paris-Sud, CNRS UMR 8619, 91405-Orsay, France.

|October 25, 2007

Summary

Viral capsid assembly is constrained by protein structure. Key residues at subunit interfaces are highly conserved, crucial for viral self-assembly and evolution.

Area of Science:

Structural biology
Virology
Evolutionary biology

Background:

Viral capsids are protein shells protecting viral genomes.
Capsid structure and assembly are critical for viral life cycles.
Understanding evolutionary constraints on viral proteins is essential.

Purpose of the Study:

To investigate evolutionary constraints on viral proteins.
To link protein sequence conservation to capsid structure and assembly.
To identify residues critical for viral capsid formation.

Main Methods:

Calculated Shannon entropies for aligned sequences of 45 polypeptide chains from 32 icosahedral viruses.
Correlated residue entropy with location in the 3D capsid structure.
Analyzed residue conservation at subunit interfaces.

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In Vitro Disassembly of Influenza A Virus Capsids by Gradient Centrifugation

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Generation and Assembly of Virus-Specific Nucleocapsids of the Respiratory Syncytial Virus

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Structure of HIV-1 Capsid Assemblies by Cryo-electron Microscopy and Iterative Helical Real-space Reconstruction

Structure of HIV-1 Capsid Assemblies by Cryo-electron Microscopy and Iterative Helical Real-space Reconstruction

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In Vitro Disassembly of Influenza A Virus Capsids by Gradient Centrifugation

In Vitro Disassembly of Influenza A Virus Capsids by Gradient Centrifugation

Published on: March 27, 2016

Main Results:

Residues buried within subunits (protein core) and at subunit interfaces (interface core) show lower than average entropy, indicating higher conservation.
The interface core is conserved across different protein complex types.
Most capsid residues (66%) are involved in at least one interface, with 34% in multiple interfaces.
Significant variation in residue conservation exists between and within capsid interfaces.
Conserved interfaces and interface regions are vital for capsid self-assembly.

Conclusions:

Specific residue locations, particularly at subunit interfaces, are under strong evolutionary constraint.
These conserved residues play critical roles in the mechanism of viral capsid self-assembly.
Findings provide insights into viral evolution and potential therapeutic targets.