FIG. 10.

Multiple alignment of amino acid sequences of gamma peptides from four insect nodaviruses: BBV, FHV, Boolarra virus (BoV), and NoV. Arrow indicates site of maturation cleavage. Shaded residues are identical in all viruses, whereas hatched residues are conserved. In BBV, FHV, and NoV, whose structures are known at high resolution, gamma peptides located at position C on the icosahedral surface lattice contact the phosphodiester backbone of encapsidated RNA via positively charged side chains at positions 371 and 375. Boxed phenylalanine residues at positions 402, 405, and 407 of FHV are required for specific encapsidation of the viral RNAs by coat precursor protein alpha.