A Strategy for O-Glycoproteomics of Enveloped Viruses-the O-Glycoproteome of Herpes Simplex Virus Type 1

TY - JOUR

T1 - A Strategy for O-Glycoproteomics of Enveloped Viruses-the O-Glycoproteome of Herpes Simplex Virus Type 1

AU - Bagdonaite, Ieva

AU - Nordén, Rickard

AU - Joshi, Hiren J

AU - Dabelsteen, Sally

AU - Nyström, Kristina

AU - Vakhrushev, Sergey Y

AU - Olofsson, Sigvard

AU - Wandall, Hans H

PY - 2015/4/1

Y1 - 2015/4/1

N2 - Glycosylation of viral envelope proteins is important for infectivity and interaction with host immunity, however, our current knowledge of the functions of glycosylation is largely limited to N-glycosylation because it is difficult to predict and identify site-specific O-glycosylation. Here, we present a novel proteome-wide discovery strategy for O-glycosylation sites on viral envelope proteins using herpes simplex virus type 1 (HSV-1) as a model. We identified 74 O-linked glycosylation sites on 8 out of the 12 HSV-1 envelope proteins. Two of the identified glycosites found in glycoprotein B were previously implicated in virus attachment to immune cells. We show that HSV-1 infection distorts the secretory pathway and that infected cells accumulate glycoproteins with truncated O-glycans, nonetheless retaining the ability to elongate most of the surface glycans. With the use of precise gene editing, we further demonstrate that elongated O-glycans are essential for HSV-1 in human HaCaT keratinocytes, where HSV-1 produced markedly lower viral titers in HaCaT with abrogated O-glycans compared to the isogenic counterpart with normal O-glycans. The roles of O-linked glycosylation for viral entry, formation, secretion, and immune recognition are poorly understood, and the O-glycoproteomics strategy presented here now opens for unbiased discovery on all enveloped viruses.

AB - Glycosylation of viral envelope proteins is important for infectivity and interaction with host immunity, however, our current knowledge of the functions of glycosylation is largely limited to N-glycosylation because it is difficult to predict and identify site-specific O-glycosylation. Here, we present a novel proteome-wide discovery strategy for O-glycosylation sites on viral envelope proteins using herpes simplex virus type 1 (HSV-1) as a model. We identified 74 O-linked glycosylation sites on 8 out of the 12 HSV-1 envelope proteins. Two of the identified glycosites found in glycoprotein B were previously implicated in virus attachment to immune cells. We show that HSV-1 infection distorts the secretory pathway and that infected cells accumulate glycoproteins with truncated O-glycans, nonetheless retaining the ability to elongate most of the surface glycans. With the use of precise gene editing, we further demonstrate that elongated O-glycans are essential for HSV-1 in human HaCaT keratinocytes, where HSV-1 produced markedly lower viral titers in HaCaT with abrogated O-glycans compared to the isogenic counterpart with normal O-glycans. The roles of O-linked glycosylation for viral entry, formation, secretion, and immune recognition are poorly understood, and the O-glycoproteomics strategy presented here now opens for unbiased discovery on all enveloped viruses.

U2 - 10.1371/journal.ppat.1004784

DO - 10.1371/journal.ppat.1004784

M3 - Journal article

C2 - 25830354

SN - 1553-7366

VL - 11

SP - 1

EP - 22

JO - P L o S Pathogens

JF - P L o S Pathogens

IS - 4

M1 - e1004784

ER -