Preserving Hard and Delicate Structures: Sample Preparation for Histology and Electron Microscopy of Hatching Freshwater Sponge Gemmules

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Abstract

Many objects of developmental biology are structurally heterogeneous, being composed of diverse tissues that present unique challenges for sample preparation and microscopic analysis. Adapting protocols to these structural peculiarities is, therefore, a crucial step for investigations in this field. A prime example is the hatching gemmule of the freshwater sponge Ephydatia fluviatilis (Linnaeus, 1759), which comprises a central cell mass surrounded by a rigid outer shell with silicious spicules, and a delicate migratory front composed of cells leaving the gemmule and spreading along the substrate. The objective of our study was to optimize sample preparation protocols to investigate the migratory behavior of cells during early E. fluviatilis development using histology, scanning electron microscopy, and transmission electron microscopy.

About the authors

E. I Andronova

Koltzov Institute of Developmental Biology, Russian Academy of Sciences

Email: andronova_e.i@mail.ru
ORCID iD: 0009-0001-2358-7997
Moscow, Russian Federation

A. I Bogomolov

Koltzov Institute of Developmental Biology, Russian Academy of Sciences

Email: bogomolov.anton2000@gmail.com
ORCID iD: 0009-0003-6737-9764
Moscow, Russian Federation

A. I Lavrov

Pertsov White Sea Biological Station, Faculty of Biology, Lomonosov Moscow State University

Email: lavrovai.bio@yandex.ru
ORCID iD: 0000-0002-0788-9039
Primorsky, Karelian Republic, Russian Federation

A. M Sokolova

Koltzov Institute of Developmental Biology, Russian Academy of Sciences

Email: agnisokolova@gmail.com
ORCID iD: 0000-0002-2056-1310
Moscow, Russian Federation

E. E Voronezhskaya

Koltzov Institute of Developmental Biology, Russian Academy of Sciences

Email: elena.voronezhskaya@idbras.ru
ORCID iD: 0000-0002-9953-2538
Moscow, Russian Federation

A. V Ereskovsky

Koltzov Institute of Developmental Biology, Russian Academy of Sciences; Aix-Marseille University, Avignon Université

Email: aereksovsky@mail.ru
ORCID iD: 0000-0003-1079-7204
Moscow, Russian Federation; Marseille, France

Yu. A Kraus

Koltzov Institute of Developmental Biology, Russian Academy of Sciences; Faculty of Biology, Lomonosov Moscow State University

Email: yuliakraus2@mail.ru
ORCID iD: 0000-0003-1916-4200
Moscow, Russian Federation

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