Abstract
The leaf blade of Arundinella hirta has mesophyll cells (MCs) and two types of Kranz cells, bundle sheath cells and distinctive cells (DCs). These cells were differentiated in the leaf sheath, culm, and rachilla as well as the leaf blade. In these organs, DCs occurred in single or multiple cell files. In these mature organs, PEPC and Rubisco were detected in MC cytosol and Kranz cell chloroplasts, respectively. PPDK mainly occurred in MC chloroplasts. However, the accumulation levels in these organs were lower than those in the blade. In the sheath and rachilla, the MCs distant from Kranz cells showed similar chloroplast structure and enzyme accumulation level to those adjacent to Kranz cells. In the basal position of developing leaf sheath, Rubisco occurred in all photosynthetic cells. Up to more apical positions, Rubisco became restricted to Kranz cells and C4 enzymes were localized in MCs.
