Measles virus blind to its epithelial cell receptor remains virulent in rhesus monkeys but cannot cross the airway epithelium and is not shed
J. Clin. Invest. Vincent H.J. Leonard, et al. 118:2448 doi:10.1172/JCI35454 [Go to this article.]

Figure 2
H protein residues relevant for EpR-dependent fusion. (A) Amino acid sequence 382–617 of the wild-type MV H protein. Homology of MV to CDV and rinderpest virus (RV) H proteins (NCBI protein sequence database accession numbers NP_056923, AAD18008, and AAD25093) is indicated as follows: asterisks (*), identical residues; colons (:), conserved residues; periods (.), semiconserved residues. The letters above the alignment denote mutants produced as single (individual letter) or double substitutions (contiguous residues; only the double mutant 442–444 is not contiguous) to alanine (A, polar residues) or serine (S, nonpolar residues). The H protein secondary structure is shown below the MV H sequence, with arrows indicating β-strands and boxes indicating α-helixes. Cyan, pink, blue, and green indicate the predicted propeller sheets 3–6, respectively. (B) Fusion efficiency of the H protein mutants in Vero/hSLAM or H358 cells. Each mutant is represented as a rectangle located at the appropriate position. Filled rectangles indicate full fusion activity; white rectangles, no fusion activity; partially filled rectangles, intermediate fusion levels. Mutants with unaltered SLAM-mediated fusion and no EpR-mediated fusion are indicated by asterisks. (C) Top view of the H protein crystal structure (25) in a ribbon plot (left) and space-filling (right) representation. The structure is color coded as in A; β-sheets 1 and 2 are indicated in yellow and red, respectively. Red: residues whose mutation abolished EpR-dependent fusion while completely retaining SLAM-dependent fusion; yellow: residues whose mutation abolished EpR-dependent fusion while strongly or moderately impairing SLAM-dependent fusion function; purple: residues important for SLAM-induced fusion.