N-terminal alpha-helix-independent membrane interactions facilitate adenovirus protein VI induction of membrane tubule formation

作者：Maier Oana; Wiethoff Christopher M^*

来源：Virology, 2010, 408(1): 31-38.

DOI：10.1016/j.viro1.2010.08.033

• Nonenveloped
• Adenovirus
• Protein VI
• Capsid
• Cell membrane

Adenovirus disrupts endosomal membranes during cell entry. The membrane lytic capsid protein VI (pVI) facilitates entry by fragmenting membranes. Although an N-terminal amphipathic alpha-helix (VI-phi) possesses similar membrane affinity as pVI, truncated protein lacking VI-phi (VI Delta 54) still possesses moderate membrane affinity. We demonstrate that incorporation of nickel-NTA lipids in membranes enhances the membrane affinity and the membrane lytic activity of VI Delta 54. We also demonstrate that 3 predicted pVI alpha-helices within residues 54-114 associate with membranes, sitting roughly parallel to the membrane surface. His-tagged VI Delta 54 is capable of fragmenting membranes similar to pVI and the VI-phi peptide. Interestingly, neither VI-phi nor His-tagged VI Delta 54 can induce tubule formation in giant lipid vesicles as observed for pVI. These data suggest cooperativity between the amphipathic a-helix and residues in VI Delta 54 to induce positive membrane curvature and tubule formation. These results provide additional details regarding the mechanism of nonenveloped virus membrane penetration.

• 出版日期2010-12-5