title: Label-free in situ imaging of oil body dynamics and chemistry in germination.
abstract: Plant oleosomes are uniquely emulsified lipid reservoirs that serve as the primary energy source during seed germination. These oil bodies undergo significant changes regarding their size, composition and structure during normal seedling development; however, a detailed characterization of these oil body dynamics, which critically affect oil body extractability and nutritional value, has remained challenging because of a limited ability to monitor oil body location and composition during germination in situ Here, we demonstrate via in situ, label-free imaging that oil bodies are highly dynamic intracellular organelles that are morphologically and biochemically remodelled extensively during germination. Label-free, coherent Raman microscopy (CRM) combined with bulk biochemical measurements revealed the temporal and spatial regulation of oil bodies in native soya bean cotyledons during the first eight days of germination. Oil bodies undergo a cycle of growth and shrinkage that is paralleled by lipid and protein compositional changes. Specifically, the total protein concentration associated with oil bodies increases in the first phase of germination and subsequently decreases. Lipids contained within the oil bodies change in saturation and chain length during germination. Our results show that CRM is a well-suited platform to monitor in situ lipid dynamics and local chemistry and that oil bodies are actively remodelled during germination. This underscores the dynamic role of lipid reservoirs in plant development.
authors: Department of Molecular Spectroscopy, Max Planck Institute for Polymer Research, Mainz, Germany.
authors: Gustav
authors: G
authors: Waschatko
authors: Department of Molecular Spectroscopy, Max Planck Institute for Polymer Research, Mainz, Germany.
authors: Nils
authors: N
authors: Billecke
authors: Department of Molecular Spectroscopy, Max Planck Institute for Polymer Research, Mainz, Germany.
authors: Sascha
authors: S
authors: Schwendy
authors: Department of Polymer Theory, Max Planck Institute for Polymer Research, Mainz, Germany.
authors: Henriette
authors: H
authors: Jaurich
authors: Department of Molecular Spectroscopy, Max Planck Institute for Polymer Research, Mainz, Germany.
authors: Mischa
authors: M
authors: Bonn
authors: Department of Polymer Theory, Max Planck Institute for Polymer Research, Mainz, Germany.
authors: Thomas A
authors: TA
authors: Vilgis
authors: Department of Molecular Spectroscopy, Max Planck Institute for Polymer Research, Mainz, Germany parekh@mpip-mainz.mpg.de.
authors: Sapun H
authors: 0000-0001-8522-1854
authors: SH
authors: Parekh
mesh_terms: D018548:Cotyledon / Q000166:cytology / Q000378:metabolism*; D018525:Germination / Q000502:physiology*; D066292:Lipid Droplets / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism*; D013025:Glycine max / Q000166:cytology / Q000254:growth & development*; D013059:Spectrum Analysis, Raman
chemical_list: D010940:Plant Proteins
keywords: Raman imaging; coherent Raman microscopy; emulsions; lipid droplets; oil bodies; plant lipids