Tyrosine cross-linking reveals interfacial dynamics in adeno-associated viral capsids during infection.

Published

Journal Article

Viral capsid dynamics are often observed during infectious events such as cell surface attachment, entry and genome release. Structural analysis of adeno-associated virus (AAV), a helper-dependent parvovirus, revealed a cluster of surface-exposed tyrosine residues at the icosahedral two-fold symmetry axis. We exploited the latter observation to carry out selective oxidation of Tyr residues, which yielded cross-linked viral protein (VP) subunit dimers, effectively "stitching" together the AAV capsid two-fold interface. Characterization of different Tyr-to-Phe mutants confirmed that the formation of cross-linked VP dimers is mediated by dityrosine adducts and requires the Tyr704 residue, which crosses over from one neighboring VP subunit to the other. When compared to unmodified capsids, Tyr-cross-linked AAV displayed decreased transduction efficiency in cell culture. Surprisingly, further biochemical and quantitative microscopy studies revealed that restraining the two-fold interface hinders externalization of buried VP N-termini, which contain a phospholipase A2 domain and nuclear localization sequences critical for infection. These adverse effects caused by tyrosine oxidation support the notion that interfacial dynamics at the AAV capsid two-fold symmetry axis play a role in externalization of VP N-termini during infection.

Full Text

Duke Authors

Cited Authors

  • Horowitz, ED; Finn, MG; Asokan, A

Published Date

  • June 2012

Published In

Volume / Issue

  • 7 / 6

Start / End Page

  • 1059 - 1066

PubMed ID

  • 22458529

Pubmed Central ID

  • 22458529

Electronic International Standard Serial Number (EISSN)

  • 1554-8937

International Standard Serial Number (ISSN)

  • 1554-8929

Digital Object Identifier (DOI)

  • 10.1021/cb3000265

Language

  • eng