Fig. 1.

BUNV glycoprotein Gc mutants. The layout of the BUNV M segment-encoded gene product is shown at the top, with positions of amino acid residues marking protein boundaries (Gn, NSm and Gc) indicated. Below are shown schematics of the proteins encoded by wt and mutant (MΔ1, etc.) cDNA clones. Deletions start at residue 480 to keep intact the cleavage site between NSm and Gc. The N-terminal position of each mutant Gc protein and the number of residues (aa) deleted are shown. The M segment gene products of MAGV and its two non-ts revertant viruses R1 and R2 (Pollitt et al., 2006) are shown beneath. Predicted transmembrane domains (TMD) and the fusion peptide (FP) in BUNV Gc (residues 1058–1079) are shown as grey and hatched boxes, respectively. ⧫ indicate glycosylation sites. Viruses recovered from mutant M segment cDNAs by reverse genetics are marked with an asterisk (*).