Development of protein bodies in cotyledons of Fagus sylvatica

Electron microscopic analysis of cotyledons of beech ( Fagus sylvatica ) at different stages of seed maturation indicates that protein bodies originate by gradual subdivision of the vacuoles in which reserve proteins are deposited. The majority of protein bodies show a proteinaceous matrix and a number of globoid inclusions of different sizes. In a small number of cells, druse-like inclusions were observed. Analysis by SDS-PAGE of proteins extracted from isolated protein bodies shows that the majority correspond to beech seed storage globulins.