Fig. 4

Subcellular localization of EGFP-OsHKT1;4 in rice protoplasts. EGFP-OsHKT1;4 protein was transiently expressed in protoplasts of rice seedlings under the control of the cauliflower mosaic virus 35S promoter. Fluorescence was analyzed by confocal microscopy. a, EGFP fluorescence (green) from a single focal plane of a representative rice protoplast co-expressing chimeric EGFP-OsHKT1;4 protein and CBL1n-OFP. b, OFP fluorescence (red) from the same protoplast as shown in a. c, Overlay image of a and b. d, Bright field image of the protoplast shown in a. e, EGFP fluorescence (green) from a single focal plane of a representative rice protoplast expressing free EGFP protein. f, OFP fluorescence from CBL1n-OFP, co-expressed in the same protoplast as shown in e. g, Overlay image of e and f. h, Bright field image of the protoplast shown in e. i, EGFP fluorescence (green) from a single focal plane of a representative rice protoplast co-expressing chimeric EGFP-OsHKT1;4 protein and ER-mCherry. j, mCherry fluorescence (red) marking the endoplasmic reticulum (ER) of the same protoplast as shown in i. k, Overlay image of i and j. l, Bright field image of the protoplast shown in i. m, EGFP fluorescence (green) from an internal single focal plane of a representative rice protoplast co-expressing chimeric EGFP-OsHKT1;4 protein and Golgi-mCherry (white arrows indicate punctate structures labeled by EGFP). n, mCherry fluorescence marking the Golgi apparatus (GA) of the same protoplast as shown in m (white arrows indicate typical GA structures). o, Overlay image of m and n showing partial co-localization of EGFP and mCherry fluorescence (corresponding to GA structures marked by arrows in N) with some punctate-like structures labeled with the EGFP alone. p, Bright field image of the protoplast shown in m