Fig 1.

The HSV-1 gB cytodomain is important for fusion regulation. (A) Schematic representation of the five proteins necessary for membrane fusion: viral glycoproteins gB, gD, gH, and gL and the cellular gD receptor. (B) Known syn point mutations (letters), truncations (arrows), and insertions (triangles) in HSV-1 and HSV-2 gB are superimposed on the primary amino acid sequence of the HSV-1 gB cytodomain. Asterisks indicate mutations in HSV-2 where the WT amino acid (not shown) differs from the HSV-1 sequence. Predicted secondary-structure elements (JPred) are shown below the sequence. Helix h1 is predicted to be contiguous with the transmembrane helix when the latter is included in secondary-structure predictions, as indicated by the dotted line and partial shading of helix h1 for residues 796 to 810. (C) Representative constructs used for expression of full-length gB proteins in CHO cells. (D) Representative constructs used to express His₆-tagged gB cytodomains in E. coli.