Effect of high‐pressure freezing on plant microfilament bundles

SUMMARY Cell structures, particularly cytoskeletal elements, of tobacco ( Nicotiana tabacum L. Var. Maryland Mammoth ) leaf tissues were studied after high‐pressure freezing and freeze substitution. In general, the freezing quality was superb and all organelles including microtubules, single microfilaments and microtubule‐associated microfilaments were well preserved. However, when compared with those frozen with a propane jet freezer, the microfilament bundles in high‐pressure frozen cells often had a frayed or loosened appearance. We suggest that such an appearance is an artefact, presumably caused by the high pressure developed prior to freezing.