Subcellular localization of the MpCHK1 and the PpCHK4 protein fused to GFP and expressed in leaves of N. benthamiana. A1-3; B1-3: GFP:MpCHK1; C1-3; D1-3: GFP:PpCHK4. Both receptor proteins were expressed transiently in tobacco leaves as fusion proteins with GFP under the control of the 35 CaMV promoter. Fluorescence was analyzed 7 days after infiltration in prepared leaf epidermal cells. A1, B1, C1, and D1 show the GFP fluorescence exited at 488 nm, emission detected at 509 nm; A2 and C2 show fluorescence at 625-665 nm of FM4-64 dye, staining the plasma membrane; B2 and D2 show the fluorescence exited at 587 nm, emission detected at 610 nm of mCherry-HDEL, staining the ER; A3, B3, C3 and D3 show an overlay from fluorescent channels. Scale bars, where shown, correspond to 25 μm.