Figure 1

Pollen-grain development. (a) A schematic representation of the stages of pollen development. (b) Arabidopsis pollen grains (Columbia accession), stained with DAPI to show DNA, at the stages indicated in (a). The larger uncondensed vegetative-cell nucleus (VCN; diffuse staining) and the condensed nuclei of one generative cell and two sperm cells (brighter dots in (b); GCN, generative-cell nucleus and SCN, sperm-cell nucleus) can be seen in the bicellular and tricellular pollen grains, respectively. The scale bar represents 10 μm. Adapted from [4, 5].