title: Deletion of a Predicted β-Sheet Domain within the Amino Terminus of Herpes Simplex Virus Glycoprotein K Conserved among Alphaherpesviruses Prevents Virus Entry into Neuronal Axons.
abstract: We have shown previously that herpes simplex virus 1 (HSV-1) lacking expression of the entire glycoprotein K (gK) or expressing gK with a 38-amino-acid deletion (gKΔ31-68 mutation) failed to infect ganglionic neurons after ocular infection of mice. We constructed a new model for the predicted three-dimensional structure of gK, revealing that the gKΔ31-68 mutation spans a well-defined β-sheet structure within the amino terminus of gK, which is conserved among alphaherpesviruses. The HSV-1(McKrae) gKΔ31-68 virus was tested for the ability to enter into ganglionic neuronal axons in cell culture of explanted rat ganglia using a novel virus entry proximity ligation assay (VEPLA). In this assay, cell surface-bound virions were detected by the colocalization of gD and its cognate receptor nectin-1 on infected neuronal surfaces. Capsids that have entered into the cytoplasm were detected by the colocalization of the virion tegument protein UL37, with dynein required for loading of virion capsids onto microtubules for retrograde transport to the nucleus. HSV-1(McKrae) gKΔ31-68 attached to cell surfaces of Vero cells and ganglionic axons in cell culture as efficiently as wild-type HSV-1(McKrae). However, unlike the wild-type virus, the mutant virus failed to enter into the axoplasm of ganglionic neurons. This work suggests that the amino terminus of gK is a critical determinant for entry into neuronal axons and may serve similar conserved functions for other alphaherpesviruses.
  
  
  OBJECTIVE
  Alphaherpesviruses, unlike beta- and gammaherpesviruses, have the unique ability to infect and establish latency in neurons. Glycoprotein K (gK) and the membrane protein UL20 are conserved among all alphaherpesviruses. We show here that a predicted β-sheet domain, which is conserved among alphaherpesviruses, functions in HSV-1 entry into neuronal axons, suggesting that it may serve similar functions for other herpesviruses. These results are in agreement with our previous observations that deletion of this gK domain prevents the virus from successfully infecting ganglionic neurons after ocular infection of mice.
authors.affiliation: Division of Biotechnology and Molecular Medicine and Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA.
authors.forename: Nithya
authors.initials: N
authors.lastname: Jambunathan
authors.affiliation: Division of Biotechnology and Molecular Medicine and Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA.
authors.forename: Anu-Susan
authors.initials: AS
authors.lastname: Charles
authors.affiliation: Division of Biotechnology and Molecular Medicine and Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA.
authors.forename: Ramesh
authors.initials: R
authors.lastname: Subramanian
authors.affiliation: Division of Biotechnology and Molecular Medicine and Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA.
authors.forename: Ahmad A
authors.initials: AA
authors.lastname: Saied
authors.affiliation: Department of Biological Sciences, College of Basic Science, Louisiana State University, Baton Rouge, Louisiana, USA.
authors.forename: Misagh
authors.initials: M
authors.lastname: Naderi
authors.affiliation: Division of Biotechnology and Molecular Medicine and Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Rider
authors.affiliation: Department of Biological Sciences, College of Basic Science, Louisiana State University, Baton Rouge, Louisiana, USA.
authors.forename: Michal
authors.initials: M
authors.lastname: Brylinski
authors.affiliation: Division of Biotechnology and Molecular Medicine and Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA.
authors.forename: Vladimir N
authors.initials: VN
authors.lastname: Chouljenko
authors.affiliation: Division of Biotechnology and Molecular Medicine and Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA vtgusk@lsu.edu.
authors.forename: Konstantin G
authors.initials: KG
authors.lastname: Kousoulas
mesh_terms: D000818:Animals; D001369:Axons / Q000821:virology*; D002478:Cells, Cultured; D002522:Chlorocebus aethiops; D045888:Ganglion Cysts / Q000821:virology; D018259:Herpesvirus 1, Human / Q000235:genetics / Q000502:physiology*; D017207:Rats, Sprague-Dawley; D017384:Sequence Deletion; D014764:Viral Proteins / Q000235:genetics*; D056189:Viral Tropism; D053586:Virus Internalization
chemical_list: C072448:UL53 protein, Human herpesvirus 1; D014764:Viral Proteins