Colocalization of TAN1 and cortical microtubules in N. benthamiana (tobacco). (A and B) TAN1-GFP (green) and RFP-TUBULIN–labeled microtubules (magenta) colocalize (merged image) when expressed transiently in tobacco epidermal cells. (C) RFP-TUBULIN was only expressed transiently in tobacco cells. Scale bars, 20 µm. Bright oval signals in guard cells in C are chloroplast autofluorescence.