An N-terminal domain of adenovirus protein VI fragments membranes by inducing positive membrane curvature

Virology. 2010 Jun 20;402(1):11-9. doi: 10.1016/j.virol.2010.03.043. Epub 2010 Apr 20.

Abstract

Adenovirus (Ad) membrane penetration during cell entry is poorly understood. Here we show that antibodies which neutralize the membrane lytic activity of the Ad capsid protein VI interfere with Ad endosomal membrane penetration. In vitro studies using a peptide corresponding to an N-terminal amphipathic alpha-helix of protein VI (VI-Phi), as well as other truncated forms of protein VI suggest that VI-Phi is largely responsible for protein VI binding to and lysing of membranes. Additional studies suggest that VI-Phi lies nearly parallel to the membrane surface. Protein VI fragments membranes and induces highly curved structures. Further studies suggest that protein VI induces positive membrane curvature. These data support a model in which protein VI binds membranes, inducing positive curvature strain which ultimately leads to membrane fragmentation. These results agree with previous observations of Ad membrane permeabilization during cell entry and provide an initial mechanistic description of a nonenveloped virus membrane lytic protein.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoviridae / physiology*
  • Capsid Proteins / genetics
  • Capsid Proteins / physiology*
  • Cell Line
  • Cell Membrane / metabolism*
  • Cell Survival
  • Humans
  • Models, Biological
  • Protein Structure, Tertiary
  • Sequence Deletion
  • Virus Internalization*

Substances

  • Capsid Proteins
  • polypeptide VI, adenovirus