C4A and infection: When we inoculated 16c-TGS transgenic N. benthamiana plants with TLCYnV or the TLCYnV-C4(S43A) mutant, we found that infection by TLCYnV restores GFP expression at 12 dpi, but the TLCYnV mutant fails to do so (Fig 6D and 6E).