title: Herpes simplex virus type 1 capsid protein VP26 interacts with dynein light chains RP3 and Tctex1 and plays a role in retrograde cellular transport.
abstract: Cytoplasmic dynein is the major molecular motor involved in minus-end-directed cellular transport along microtubules. There is increasing evidence that the retrograde transport of herpes simplex virus type 1 along sensory axons is mediated by cytoplasmic dynein, but the viral and cellular proteins involved are not known. Here we report that the herpes simplex virus outer capsid protein VP26 interacts with dynein light chains RP3 and Tctex1 and is sufficient to mediate retrograde transport of viral capsids in a cellular model. A library of herpes simplex virus capsid and tegument structural genes was constructed and tested for interactions with dynein subunits in a yeast two-hybrid system. A strong interaction was detected between VP26 and the homologous 14-kDa dynein light chains RP3 and Tctex1. In vitro pull-down assays confirmed binding of VP26 to RP3, Tctex1, and intact cytoplasmic dynein complexes. Recombinant herpes simplex virus capsids were constructed either with or without VP26. In pull-down assays VP26+ capsids bound to RP3; VP26-capsids did not. To investigate intracellular transport, the recombinant viral capsids were microinjected into living cells and incubated at 37 degrees C. After 1 h VP26+ capsids were observed to co-localize with RP3, Tctex1, and microtubules. After 2 or 4 h VP26+ capsids had moved closer to the cell nucleus, whereas VP26-capsids remained in a random distribution. We propose that VP26 mediates binding of incoming herpes simplex virus capsids to cytoplasmic dynein during cellular infection, through interactions with dynein light chains.
authors.affiliation: Centre for Virus Research, Westmead Millennium Institute, University of Sydney and Westmead Hospital, Westmead 2145, New South Wales, Australia.
authors.forename: Mark W
authors.initials: MW
authors.lastname: Douglas
authors.forename: Russell J
authors.initials: RJ
authors.lastname: Diefenbach
authors.forename: Fred L
authors.initials: FL
authors.lastname: Homa
authors.forename: Monica
authors.initials: M
authors.lastname: Miranda-Saksena
authors.forename: Frazer J
authors.initials: FJ
authors.lastname: Rixon
authors.forename: Valerio
authors.initials: V
authors.lastname: Vittone
authors.forename: Karen
authors.initials: K
authors.lastname: Byth
authors.forename: Anthony L
authors.initials: AL
authors.lastname: Cunningham
mesh_terms: D001692:Biological Transport; D015153:Blotting, Western; D002213:Capsid / Q000737:chemistry; D036022:Capsid Proteins / Q000737:chemistry / Q000378:metabolism*; D002352:Carrier Proteins / Q000737:chemistry*; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D029721:Drosophila Proteins; D004398:Dyneins; D005982:Glutathione Transferase / Q000378:metabolism; D006801:Humans; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D008869:Microtubule-Associated Proteins / Q000737:chemistry*; D008870:Microtubules / Q000378:metabolism; D009474:Neurons / Q000378:metabolism; D009687:Nuclear Proteins / Q000737:chemistry*; D011485:Protein Binding; D011994:Recombinant Proteins / Q000737:chemistry; D018139:Simplexvirus / Q000378:metabolism; D013997:Time Factors; D020798:Two-Hybrid System Techniques; D056427:t-Complex Genome Region
chemical_list: D036022:Capsid Proteins; D002352:Carrier Proteins; D029721:Drosophila Proteins; D008869:Microtubule-Associated Proteins; D009687:Nuclear Proteins; D011994:Recombinant Proteins; C077409:capsid protein VP26, herpes simplex virus type 1; D005982:Glutathione Transferase; D004398:Dyneins