A method for preparing spaceflight RNA later ‐fixed Arabidopsis thaliana (Brassicaceae) tissue for scanning electron microscopy

Abstract

• Premise of the study: In spaceflight experiments, tissues for morphologic study are fixed in 3% glutaraldehyde, while tissues for molecular study are fixed in RNA later ; thus, an experiment containing both study components requires multiple fixation strategies. The possibility of using RNA later ‐fixed materials for standard SEM‐based morphometric investigation was explored to expand the library of tissues available for analysis and maximize usage of samples returned from spaceflight, but these technologies have wide application to any situation where recovery of biological resources is limited. • Methods and Results: RNA later ‐fixed samples were desalinated in distilled water, dehydrated through graded methanol, plunged into liquid ethane, and transferred to cryovials for freeze‐substitution. Sample tissues were critical point dried, mounted, sputter‐coated, and imaged. • Conclusions: The protocol resulted in acceptable SEM images from RNA later ‐fixed Arabidopsis thaliana tissue. The majority of the tissues remained intact, including general morphology and finer details such as root hairs and trichomes.