1. 3D FIB-SEM reconstruction of microtubule-organelle interaction in whole primary mouse beta cells
- Author
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Michele Solimena, C. Shan Xu, Harald F. Hess, Song Pang, Joyson Verner D'Costa, Carla Münster, Andreas Müller, Susanne Kretschmar, Martin Weigert, Thomas Kurth, Florian Jug, and Deborah Schmidt
- Subjects
0303 health sciences ,Centriole ,Vesicle ,Cell Biology ,Biology ,Golgi apparatus ,Cell biology ,Cell membrane ,03 medical and health sciences ,symbols.namesake ,0302 clinical medicine ,medicine.anatomical_structure ,Microtubule ,Organelle ,symbols ,medicine ,Secretion ,030217 neurology & neurosurgery ,Intracellular ,030304 developmental biology - Abstract
Microtubules play a major role in intracellular trafficking of vesicles in endocrine cells. Detailed knowledge of microtubule organization and their relation to other cell constituents is crucial for understanding cell function. However, their role in insulin transport and secretion is under debate. Here, we use FIB-SEM to image islet β cells in their entirety with unprecedented resolution. We reconstruct mitochondria, Golgi apparati, centrioles, insulin secretory granules, and microtubules of seven β cells, and generate a comprehensive spatial map of microtubule–organelle interactions. We find that microtubules form nonradial networks that are predominantly not connected to either centrioles or endomembranes. Microtubule number and length, but not microtubule polymer density, vary with glucose stimulation. Furthermore, insulin secretory granules are enriched near the plasma membrane, where they associate with microtubules. In summary, we provide the first 3D reconstructions of complete microtubule networks in primary mammalian cells together with evidence regarding their importance for insulin secretory granule positioning and thus their supportive role in insulin secretion.
- Published
- 2021
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