title: Electron microscopy of flatworms standard and cryo-preparation methods.
abstract: Electron microscopy (EM) has long been indispensable for flatworm research, as most of these worms are microscopic in dimension and provide only a handful of characters recognizable by eye or light microscopy. Therefore, major progress in understanding the histology, systematics, and evolution of this animal group relied on methods capable of visualizing ultrastructure. The rise of molecular and cellular biology renewed interest in such ultrastructural research. In the light of recent developments, we offer a best-practice guide for users of transmission EM and provide a comparison of well-established chemical fixation protocols with cryo-processing methods (high-pressure freezing/freeze-substitution, HPF/FS). The organisms used in this study include the rhabditophorans Macrostomum lignano, Polycelis nigra and Dugesia gonocephala, as well as the acoel species Isodiametra pulchra.
authors.affiliation: Center for Molecular Biosciences, Institute of Zoology, University of Innsbruck, Innsbruck, Austria.
authors.forename: Willi
authors.initials: W
authors.lastname: Salvenmoser
authors.forename: Bernhard
authors.initials: B
authors.lastname: Egger
authors.forename: Johannes G
authors.initials: JG
authors.lastname: Achatz
authors.forename: Peter
authors.initials: P
authors.lastname: Ladurner
authors.forename: Michael W
authors.initials: MW
authors.lastname: Hess
mesh_terms: D000818:Animals; D015925:Cryopreservation / Q000379:methods*; D017110:Freeze Substitution / Q000379:methods; D008854:Microscopy, Electron / Q000379:methods*; D010986:Platyhelminths / Q000648:ultrastructure*; D016707:Tissue Fixation / Q000379:methods*