Various types of cell wall compositions have evolved to fulfill a wide range of biological roles during the diversification of land plants. (1;3,1;4)-β-D-glucan (MLG) is a defining feature of the cell walls in the order Poales (Yokoyama and Nishitani, 2004), which has multiple functions associated with metabolic, growth, and defense systems. MLG is also a characteristic component of the matrix polysaccharides that undergo turnover and metabolism, depending on the tissue and the stage of development (Kido et al., 2015). Determining the extracellular localization of MLG is essential for elucidating its functions. Electron microscopy immunogold labeling analysis is a useful technique, which provides an accurate representation of the extracellular distribution of MLG. This strategy is also applicable to various kinds of cell wall polysaccharides, which have key roles in regulating growth and differentiation in each plant species.
