FIG 5.

The N- and C-proximal regions and amino acids 85 to 100 of WSMV CP are required for efficient cell-to-cell movement in wheat. In vitro transcripts of GFP-tagged wild-type virus and CP deletion mutants were inoculated onto wheat seedlings at the single-leaf stage. The fluorescent foci developed by the wild-type virus and CP deletion mutants at 4 and 14 dpi are presented in the top (A1 to I1) and middle (A2 to I2) rows, respectively, and the GFP fluorescence in the upper noninoculated leaves at 12 dpi (21 dpi for WSMV-CPΔC17aa and WSMV-CPΔN6-27aa mutant viruses) is presented in the bottom rows (A3 to I3). Bars, 500 μm. Note that WSMV with a deletion of amino acids 36 to 84 in the CP elicited local and systemic infection foci similar to those found in wild-type virus; in contrast, deletions comprising amino acids 6 to 27 or 85 to 100 or the C-terminal 14 or 17 amino acids affected the efficiency of cell-to-cell movement in wheat.