Contents lists available at ScienceDirect Virus Research journal homepage: www.elsevier.com/locate/virusres Genetic fusion of peste des petits ruminants virus haemagglutinin and fusion protein domains to the amino terminal subunit of glycoprotein B of bovine herpesvirus 1 interferes with transport and function of gB for BHV-1 infectious replication Nussieba A. Osman a,b, ⁎ , Anja Röder a , Katrin Giesow a , Günther M. Keil a a Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institute, Federal Research Institute for Animal Health, Südufer 10, 17493 Greifswald-Insel Riems, Germany b Department of Pathology, Parasitology and Microbiology, College of Veterinary Medicine, Sudan University of Science and Technology, P.O. Box 204 Kuku, Khartoum- North, Sudan ARTICLE INFO Keywords: Peste des petits ruminants virus Haemagglutinin Fusion protein Pseudotyping Bovine herpesvirus-1 Glycoprotein B ABSTRACT Peste des petits ruminants is an emerging, often fatal viral disease of domestic and wild small ruminants caused by peste des petits ruminants virus. The haemagglutinin and the fusion protein are viral envelope glycoproteins and essential for the infection process and both induce a protective immune response in infected or vaccinated animals. Attempts to generate pseudotyped bovine herpesvirus 1 recombinants firstly by integration of ex- pression cassettes for PPRV-H and PPRV-F into the herpesviral genome or secondly to generate pseudotyped BHV-1 by genetically fusing relevant parts of both PPRV glycoproteins to the amino-terminal subunit of gly- coprotein B, approaches that had been successful for heterologous viral membrane glycoproteins in the past, failed repeatedly. We therefore analyzed at which intracellular stage generation of viable BHV-1 hybrid-gB re- combinants might be inhibited. Results obtained from transient protein expression experiments revealed that, dependent on the fusion protein, transport of the hybrid glycoproteins beyond the endoplasmic reticulum is impeded. Thus, expression of heterologous glycoproteins using BHV-1 interferes more than expected from published experience with BHV-1 gB transport and consequently with virus replication. 1. Introduction Peste des petits ruminants (PPR), is one of the most destructive and economically important diseases of domestic and wild small ruminants and is caused by peste des petits ruminants virus (PPRV), a member of the Morbillivirus genus in the Paramyxoviridae family (Gibbs et al., 1979). It is one of the animal diseases which have to be notified to the World Organization for Animal Health (OIE) due to its highly con- tagious nature and capacity for rapid spread (OIE, 2013). After its in- itial appearance in the Ivory-coast (Cote D’Ivore) in West-Africa (Gargadennec and Lalanne, 1942), the disease spread aggressively into new countries until it became prevalent in nearly most of Africa and Asia, the Middle East, Turkey, with the recent occurrence in Georgia and Mongolia (Banyard et al., 2010; Albina et al., 2013; Libeau et al., 2014; Parida et al., 2015; Baron et al., 2017). PPRV is known to infect mainly sheep and goats however outbreaks of the disease were reported in some wild small ruminants as well as in camels (Kinne et al., 2010; Parida et al., 2015; Marashi et al., 2017). The linear, non-segmented, single-stranded negative sense RNA genome of PPRV is 15.948 nucleotides (nt) in length and contains six nonoverlapping transcription units encoding six structural proteins namely: the nucleoprotein (N), the phosphoprotein (P), the matrix protein (M), the large protein or polymerase (L), the fusion protein (F) and the haemagglutinin (H), the last two being virion membrane gly- coproteins (Bailey et al., 2005; Chard et al., 2008). In addition, the P protein transcription unit encodes the C and V nonstructural proteins (Mahapatra et al., 2003). Up to now only one serotype is recognized. However, four genetic lineages (I, II, III and IV) are present, defined by differences either in partial sequences of F- (Forsyth and Barrett, 1995; Shaila et al., 1996; Dhar et al., 2002; Ozkul et al., 2002), N- (Couacy- Hymann et al., 2002; Kwiatek et al., 2007) or H- open reading frames (Kaul, 2004; Balamurugan et al., 2010). https://doi.org/10.1016/j.virusres.2018.09.015 Received 2 August 2018; Received in revised form 21 September 2018; Accepted 21 September 2018 ⁎ Corresponding author at: Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institute, Federal Research Institute for Animal Health, Südufer 10, 17493 Greifswald-Insel Riems, Germany. E-mail address: nussieba@yahoo.com (N.A. Osman). Virus Research 258 (2018) 9–18 Available online 26 September 2018 0168-1702/ © 2018 Elsevier B.V. All rights reserved. T