Astrovirus Structure and Assembly

  • Rebecca M. Dubois
  • Kelly A. Dryden
  • Mark Yeager
  • Yizhi J. Tao


Recent structural studies on the astrovirus virion and viral proteins have yielded exciting new insights into the molecular mechanisms of the astrovirus life cycle. The 25 Å-resolution cryo-electron microscopy (Cryo-EM) reconstructions of the astrovirus virion reveal a solid capsid shell studded with spikes. Proteolytic maturation of the virus particle results in capsid conformational changes, most prominently at the spikes. High-resolution crystal structures of the human and avian astrovirus capsid spike domains have shed light on potential host receptors and species specificity. Together, both the structural studies on the astrovirus virion and capsid spike domains have revealed similarities to hepatitis E virus, suggesting an evolutionary relationship. The only other structural information on astrovirus is from the high-resolution crystal structure of the protease that is involved in nonstructural polyprotein processing. Overall, these structural studies have led a better understanding of the astrovirus life cycle, including astrovirus assembly, virus release, maturation, receptor binding, antibody neutralization, and nonstructural polyprotein processing.


Dime Interface Trypsin Cleavage Projection Domain Capsid Shell Surface Spike 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The authors are supported by the Welch Foundation (C-1565 to YJT) and the National Institutes of Health (R01 GM066087 to MY).


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Copyright information

© Springer Science+Business Media New York 2012

Authors and Affiliations

  • Rebecca M. Dubois
    • 1
  • Kelly A. Dryden
    • 2
  • Mark Yeager
    • 3
  • Yizhi J. Tao
    • 4
  1. 1.Department of Structural BiologySt. Jude Children’s Research HospitalMemphisUSA
  2. 2.Department of Molecular Physiology and Biological PhysicsUniversity of VirginiaCharlottesvilleUSA
  3. 3.Department of Molecular Physiology and Biological PhysicsUniversity of VirginiaCharlottesvilleUSA
  4. 4.Department of Biochemistry and Cell BiologyRice UniversityHoustonUSA

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