The murine cytomegalovirus (MCMV) M33 gene is conserved among all betaherpesviruses and encodes a homologue of seven-transmembrane receptors (7TMR) with the capacity for constitutive signaling. Previous studies have demonstrated that M33 is important for MCMV dissemination to or replication within the salivary glands. In this study, we probed N-and C-terminal regions of M33 as well as known 7TMR signature motifs in transmembrane (TM) II and TM III to determine the impact on cell surface expression, constitutive signaling, and in vivo phenotype. The region between amino acids R 340 and A 353 of the C terminus was found to be important for CREB-and NFAT-mediated signaling, although not essential for phosphatidylinositol turnover. Tagging or truncation of the N terminus of M33 resulted in loss of cell surface expression. Within TM II, an F79D mutation abolished constitutive signaling, demonstrating a role, as in other cellular and viral 7TMR, of TM II in receptor activation. In TM III, the arginine (but not the asparagine) residue of the NRY motif (the counterpart of the common DRY motif in cellular 7TMR) was found to be essential for constitutive signaling. Selected mutations incorporated into recombinant MCMV showed that disruption of constitutive signaling for a viral 7TMR homologue resulted in a reduced capacity to disseminate to or replicate in the salivary glands. In addition, HCMV UL33 was found to partially compensate for the lack of M33 in vivo, suggesting conserved biological roles of the UL33 gene family.

BackgroundAfrican horse sickness virus (AHSV) causes a non-contagious, infectious disease in equids, with mortality rates that can exceed 90% in susceptible horse populations. AHSV vaccines play a crucial role in the control of the disease; however, there are concerns over the use of polyvalent live attenuated vaccines particularly in areas where AHSV is not endemic. Therefore, it is important to consider alternative approaches for AHSV vaccine development. We have carried out a pilot study to investigate the ability of recombinant modified vaccinia Ankara (MVA) vaccines expressing VP2, VP7 or NS3 genes of AHSV to stimulate immune responses against AHSV antigens in the horse.Methodology/Principal FindingsVP2, VP7 and NS3 genes from AHSV-4/Madrid87 were cloned into the vaccinia transfer vector pSC11 and recombinant MVA viruses generated. Antigen expression or transcription of the AHSV genes from cells infected with the recombinant viruses was confirmed. Pairs of ponies were vaccinated with MVAVP2, MVAVP7 or MVANS3 and both MVA vector and AHSV antigen-specific antibody responses were analysed. Vaccination with MVAVP2 induced a strong AHSV neutralising antibody response (VN titre up to a value of 2). MVAVP7 also induced AHSV antigen–specific responses, detected by western blotting. NS3 specific antibody responses were not detected.ConclusionsThis pilot study demonstrates the immunogenicity of recombinant MVA vectored AHSV vaccines, in particular MVAVP2, and indicates that further work to investigate whether these vaccines would confer protection from lethal AHSV challenge in the horse is justifiable.

Equid herpesvirus 2 (EHV-2), in common with other members of the subfamily Gammaherpesvirinae, encodes homologues of cellular seven-transmembrane receptors (7TMR), namely open reading frames (ORFs) E1, 74 and E6, which each show some similarity to cellular chemokine receptors. Whereas ORF74 and E6 are members of gammaherpesvirus-conserved 7TMR gene families, E1 is currently unique to EHV-2. To investigate their genetic variability, EHV-2 7TMRs from a panel of equine gammaherpesvirus isolates were sequenced. A region of gB was sequenced to provide comparative sequence data. Phylogenetic analysis revealed six 'genogroups' for E1 and four for ORF74, which exhibited approximately 10-38 and 11-27 % amino acid difference between groups, respectively. In contrast, E6 was highly conserved, with two genogroups identified. The greatest variation was observed within the N-terminal domains and other extracellular regions. Nevertheless, analysis of the number of non-synonymous (d N ) and synonymous (d S ) substitutions per site generally supported the hypothesis that the 7TMRs are under negative selective pressure to retain functionally important residues, although some site-specific positive selection (d N .d S ) was also observed. Collectively, these data are consistent with transmembrane and cytoplasmic domains being less tolerant of mutations with adverse effects upon function. Finally, there was no evidence for genetic linkage between the different gB, E1, ORF74 and E6 genotypes, suggesting frequent intergenic recombination between different EHV-2 strains. INTRODUCTIONEquid herpesvirus 2 (EHV-2) is a lymphotropic herpesvirus with a high prevalence in horse populations worldwide (Borchers et al., 1997). Although the clinical significance of EHV-2 infection is uncertain, EHV-2 has been implicated in conjunctivitis, immunosuppression in foals, pneumonia, respiratory disease and poor racing performance (Collinson et al., 1994;Kershaw et al., 2001;Murray et al., 1996;Nordengrahn et al., 1996). It may also serve as a trans-activating factor to trigger or upregulate equid herpesvirus 1 (EHV-1) and equid herpesvirus 4 (EHV-4) reactivation from latency (Purewal et al., 1992;Welch et al., 1992). EHV-2 establishes latency in B lymphocytes (Drummer et al., 1996) and has been detected in peripheral blood mononuclear cells, the respiratory tract and draining lymph nodes. The virus has also been detected in both peripheral and central nervous systems (Rizvi et al., 1997). EHV-2 and the closely related equid herpesvirus 5 (EHV-5) are members of the genus Rhadinovirus of the subfamily Gammaherpesvirinae.EHV-2 encodes three homologues of cellular seventransmembrane receptors (7TMRs), also known as Gprotein-coupled receptors (GPCRs), encoded by the genes E1, E6 and ORF74 (Telford et al., 1995). Homologues of 7TMRs are characteristic of the beta-and gammaherpesvirus subfamilies and generally show similarity to cellular chemokine receptors. Chemokine receptors belong to the rhodopsin-like family of 7TMRs (Murphy et al., 2000). Their binding...

The COVID-19 pandemic and associated response have brought food security into sharp focus for many New Zealanders. The requirement to “shelter in place” for eight weeks nationwide, with only “essential services” operating, affected all parts of the New Zealand food system. The nationwide full lockdown highlighted existing inequities and created new challenges to food access, availability, affordability, distribution, transportation, and waste management. While Aotearoa New Zealand is a food producer, there remains uncertainty surrounding the future of local food systems, particularly as the long-term effects of the pandemic emerge. In this article we draw on interviews with food rescue groups, urban farms, community organisations, supermarket management, and local and central government staff to highlight the diverse, rapid, community-based responses to the COVID-19 pandemic. Our findings reveal shifts at both the local scale, where existing relationships and short supply chains have been leveraged quickly, and national scale, where funding has been mobilised towards a different food strategy. We use these findings to re-imagine where and how responsibility might be taken up differently to enhance resilience and care in diverse food systems in New Zealand.

Murine cytomegalovirus (MCMV) M78 is a member of the betaherpesvirus 'UL78 family' of seven transmembrane receptor (7TMR) genes. Previous studies of M78 and its counterpart in rat cytomegalovirus (RCMV) have suggested that these genes are required for efficient cell-cell spread of their respective viruses in tissue culture and demonstrated that gene knockout viruses are significantly attenuated for replication in vivo. However, in comparison with other CMV 7TMRs, relatively little is known about the basic biochemical properties and subcellular trafficking of the UL78 family members. We have characterized MCMV M78 in both transiently transfected and MCMV-infected cells to determine whether M78 exhibits features in common with cellular 7TMR. We obtained preliminary evidence that M78 formed dimers, a property that has been reported for several cellular 7TMR. M78 traffics to the cell surface, but was rapidly and constitutively endocytosed. Antibody feeding experiments demonstrated co-localization of M78 with markers for both the clathrin-dependent and lipid raft/caveolae-mediated internalization pathways. In MCMV-infected cells, the subcellular localization of M78 was modified during the course of infection, which may be related to the incorporation of M78 into the virion envelope during the course of virion maturation.