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Fine-tuning transmission electron microscopy methods to evaluate the cellular architecture of Ulvacean seaweeds (Chlorophyta)
journal contribution
posted on 2023-05-19, 15:59 authored by Farias, DR, Simioni, C, Poltronieri, E, Bouzon, ZL, Catriona MacLeodCatriona MacLeodChemical fixation is a critical step in the analysis of the ultrastructure of seaweeds because the wrong approach can compromise the ability to distinguish fine-scale cellular composition. Fixation agents, fixation time and type of tissue are important factors to consider for transmission electron microscopy (TEM), and not every protocol is suitable for all cell types. We evaluated a range of fixation agents, post-fixation time and dehydration solutions to determine a TEM protocol for seaweeds in the Family Ulvaceae. We assessed Ulva lactuca using 5 protocols. The level of preservation obtained differed markedly between fixation methods The best result was obtained by fixing the sample with 2.5% glutaraldehyde, 0.05 M sodium cacodylate buffer and 2% paraformaldehyde overnight, and 8 h post-fixation in 1% in osmium tetroxide 1%. This approach and fixation time ensured that the membranes, especially the thylakoid membranes of chloroplasts, remained intact. Ethanol is recommended for dehydration as the use of acetone for dehydration resulted in the collapse of cellular membranes. This new protocol will ensure the ultrastructure of Ulvacean seaweeds can be clearly ascertained in the future.
History
Publication title
MicronVolume
96Pagination
48-56ISSN
0968-4328Department/School
Institute for Marine and Antarctic StudiesPublisher
Pergamon-Elsevier Science LtdPlace of publication
The Boulevard, Langford Lane, Kidlington, Oxford, England, Ox5 1GbRights statement
Copyright 2017 Elsevier Ltd.Repository Status
- Restricted