Subcellular localization and distribution of cPGI-YFP fusion proteins in developing anthers of the partially complemented p35S::cPGI-YFP cpgi-3^(−/−) plants. A,B, Optical sections of confocal microscopy focusing on the layer of the epidermis (A) and of endothecium (B) of the same anther dissected from a 1.2-mm floral bud (corresponding to the late binucleate pollen stage in WT plants) of a sterile p35S::cPGI-YFP cpgi-3^(−/−) plant. Dual localization in the nucleus (N) and cytoplasm (Cyt) was observed in those cells expressing p35S::cPGI-YFP (Aʹ and Bʹ). C, A longitudinally optical section focusing on the locular space of an anther dissected from another 0.5-mm bud (corresponding to the meiosis pollen stage in WT plants). Note the YFP signals were detected in the epidermis, endothecium, and connecting tissues of the anther, where those cells contained differentiated chloroplasts; while the signals were undetectable in the tapetal cells (T) and the callose wall-encased meiocytes (M), in which do not contain differentiated chloroplasts (Cʹ). Parts from left to right respectively show the channel of yellow fluorescent protein (YFP), chlorophyll autofluorescence (Chl), the merged (YFP/Chl), and DIC. Bars = 20 µm.