A multipotential beta-1,6-N-acetylglucosaminyltransferase is encoded by bovine herpesvirus type 4

Citation
A. Vanderplasschen et al., A multipotential beta-1,6-N-acetylglucosaminyltransferase is encoded by bovine herpesvirus type 4, P NAS US, 97(11), 2000, pp. 5756-5761
Citations number
41
Categorie Soggetti
Multidisciplinary
Journal title
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
ISSN journal
00278424 → ACNP
Volume
97
Issue
11
Year of publication
2000
Pages
5756 - 5761
Database
ISI
SICI code
0027-8424(20000523)97:11<5756:AMBIEB>2.0.ZU;2-1
Abstract
The beta-1,6-N-acetylglucosaminyltransferase (beta 1,6GnT) gene family enco des enzymes playing crucial roles in glycan synthesis. Important changes in beta 1,6GnT expression are observed during development, oncogenesis, and i mmunodeficiency. The most characterized beta 1,6GnTs in this gene family ar e the human (h) C2GnT-L and h-IGnT, which have core 2 [Gal beta 1 --> 3(Glc NAc beta 1 --> 6)GalNAc] and 1 branching [GlcNAc beta 1 --> 3(GlcNAc beta 1 --> 6)Gal] activities, respectively. Recently, h-C2GnT-M was shown to be u nique in forming core 2, core 4 [GlcNAc beta 1 --> 3(GlcNAc beta 1 --> 6)Ga lNAc], and 1 structures. To date, the beta 1,6GnT gene family has been char acterized only in mammals. Here, we describe that bovine herpesvirus type 4 (BHV-4) encodes a beta 1,6GnT expressed during viral replication and exhib iting all of the core 2, core 4, and 1 branching activities. Sequencing of the BHV-4 genome revealed an ORF, hereafter called BORFF3-4, encoding a pro tein (pBORFF3-4) exhibiting 81.1%, 50.7%, and 36.6% amino acid identity wit h h-C2GnT-M, h-C2GnT-L, and h-IGnT, respectively. Reverse transcriptase-PCR analysis revealed that BORFF3-4 is expressed during BHV-4 replication. Exp ression of BORFF3-4 in Chinese hamster ovary cells directed the expression of core 2 branched oligosaccharides and 1 antigenic structures on the cell surface. Moreover, a soluble form of pBORFF3-4 had core 4 branching activit y in addition to core 2 and 1 branching activities. Finally, infection of a C2GnT-negative cell line with BHV-4 induced expression of core 2 branched oligosaccharides. This study extends the beta 1,6GnT gene family to a viral gene and provides a model to study the biological functions of a beta 1,6G nT in the context of viral infection.