title: Studying the Supramolecular Organization of Photosynthetic Membranes within Freeze-fractured Leaf Tissues by Cryo-scanning Electron Microscopy.
abstract: Cryo-scanning electron microscopy (SEM) of freeze-fractured samples allows investigation of biological structures at near native conditions. Here, we describe a technique for studying the supramolecular organization of photosynthetic (thylakoid) membranes within leaf samples. This is achieved by high-pressure freezing of leaf tissues, freeze-fracturing, double-layer coating and finally cryo-SEM imaging. Use of the double-layer coating method allows acquiring high magnification (>100,000X) images with minimal beam damage to the frozen-hydrated samples as well as minimal charging effects. Using the described procedures we investigated the alterations in supramolecular distribution of photosystem and light-harvesting antenna protein complexes that take place during dehydration of the resurrection plant Craterostigma pumilum, in situ.
authors.affiliation: Department of Biological Chemistry, Weizmann Institute of Science; Institute of Plant Sciences, Agricultural Research Organization, Volcani Center; charuvi@volcani.agri.gov.il.
authors.forename: Dana
authors.initials: D
authors.lastname: Charuvi
authors.affiliation: Department of Biological Chemistry, Weizmann Institute of Science.
authors.forename: Reinat
authors.initials: R
authors.lastname: Nevo
authors.affiliation: Department of Chemical Research Support, Weizmann Institute of Science.
authors.forename: Ifat
authors.initials: I
authors.lastname: Kaplan-Ashiri
authors.affiliation: Department of Chemical Research Support, Weizmann Institute of Science.
authors.forename: Eyal
authors.initials: E
authors.lastname: Shimoni
authors.affiliation: Department of Biological Chemistry, Weizmann Institute of Science.
authors.forename: Ziv
authors.initials: Z
authors.lastname: Reich
mesh_terms: D005614:Freeze Fracturing; D045342:Light-Harvesting Protein Complexes; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D010788:Photosynthesis; D018515:Plant Leaves
chemical_list: D045342:Light-Harvesting Protein Complexes