Transmission electron microscopy localization of caleosin in the olive pollen and locular fluid. Sections from olive anthers at the mid microspore (A), young pollen grain (B), mid bicellular pollen grain (C) and mature pollen grain (D) stages were treated as in figure 4. Gold labelling is indicated by arrowheads. (E) Control reaction by omitting the FL anti-Clo3 Ab showing the absence of gold labelling. CW: cell wall; Ex: exine; In: intine; L: anther locule; OB: oil body; PC: pollen coat; S: starch; TC: tapetal cell.