Using a novel CLEM system to localize lipid droplets and membranes in desiccated embryonic axis cells of soybean seeds

Abstract

Lipid droplets and membranes in radicle cells from desiccated embryonic axes of soybean (Glycine max) seeds were examined by a recently developed correlative light and electron microscopy system, which has been designed to facilitate the observation of identical locations using an upright reflected light microscope and compact SEM successively with minimum time lapse. Lipids are major components of membranes and are also stored in numerous lipid droplets lining plasma membranes in many seed cells. Fluorescently stained lipid droplets and membranes in the desiccated radicle cells were mainly located along the surface of shrunk protoplasm and around presumptive protein bodies, which will turn into vacuoles and increase their volume for radicle protrusion. Co-localization of lipid droplets and membranes suggests the presence of a membrane protection mechanism during desiccation and rehydration processes that ensures prompt elongation of radicle cells during germination.