Eclipse phase of herpes simplex virus type 1 infection: Efficient dynein-mediated capsid transport without the small capsid protein VP26

J Virol. 2006 Aug;80(16):8211-24. doi: 10.1128/JVI.02528-05.

Abstract

Cytoplasmic dynein,together with its cofactor dynactin, transports incoming herpes simplex virus type 1 (HSV-1) capsids along microtubules (MT) to the MT-organizing center (MTOC). From the MTOC, capsids move further to the nuclear pore, where the viral genome is released into the nucleoplasm. The small capsid protein VP26 can interact with the dynein light chains Tctex1 (DYNLT1) and rp3 (DYNLT3) and may recruit dynein to the capsid. Therefore, we analyzed nuclear targeting of incoming HSV1-DeltaVP26 capsids devoid of VP26 and of HSV1-GFPVP26 capsids expressing a GFPVP26 fusion instead of VP26. To compare the cell entry of different strains, we characterized the inocula with respect to infectivity, viral genome content, protein composition, and particle composition. Preparations with a low particle-to-PFU ratio showed efficient nuclear targeting and were considered to be of higher quality than those containing many defective particles, which were unable to induce plaque formation. When cells were infected with HSV-1 wild type, HSV1-DeltaVP26, or HSV1-GFPVP26, viral capsids were transported along MT to the nucleus. Moreover, when dynein function was inhibited by overexpression of the dynactin subunit dynamitin, fewer capsids of HSV-1 wild type, HSV1-DeltaVP26, and HSV1-GFPVP26 arrived at the nucleus. Thus, even in the absence of the potential viral dynein receptor VP26, HSV-1 used MT and dynein for efficient nuclear targeting. These data suggest that besides VP26, HSV-1 encodes other receptors for dynein or dynactin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Active Transport, Cell Nucleus
  • Animals
  • Capsid / metabolism*
  • Capsid Proteins / analysis
  • Capsid Proteins / genetics*
  • Cell Membrane / chemistry
  • Cell Membrane / metabolism*
  • Cells, Cultured
  • Cricetinae
  • Dynactin Complex
  • Dyneins / metabolism*
  • Gene Expression
  • Gene Expression Regulation, Viral
  • Herpes Simplex / metabolism*
  • Herpesvirus 1, Human / chemistry
  • Herpesvirus 1, Human / genetics
  • Herpesvirus 1, Human / metabolism*
  • Membrane Proteins / analysis
  • Membrane Proteins / metabolism
  • Microtubule-Associated Proteins / metabolism
  • Microtubules / metabolism
  • Protein Transport
  • Viral Plaque Assay

Substances

  • Capsid Proteins
  • DCTN2 protein, human
  • Dynactin Complex
  • Membrane Proteins
  • Microtubule-Associated Proteins
  • VP5 protein, Herpes simplex virus type 1
  • capsid protein VP26, herpes simplex virus type 1
  • Dyneins