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bioRxiv · 10.1101/2021.04.14.437159

Cryo-electron tomography of native Drosophila tissues vitrified by plunge freezing

Baeuerlein, F. J. B.·Pastor-Pareja, J. C.·Fernandez-Busnadiego, R.
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Abstract

Cryo-focused ion beam (cryo-FIB) milling allows thinning vitrified cells for high resolution imaging by cryo-electron tomography (cryo-ET). However, it remains challenging to apply this workflow to voluminous biological specimens such as tissues or particularly large mammalian cells, which usually require high-pressure freezing for vitrification. Here we show that adult mouse cardiomyocytes and dissected Drosophila tissues can be directly vitrified by plunge freezing upon a short incubation in 10% glycerol. This expedites subsequent cryo-FIB/ET, enabling systematic analyses of the molecular architecture of complex native specimens. Our data provides unanticipated insights into the molecular architecture of samples hitherto unexplored by cryo-ET.

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Baeuerlein, F. J. B., Pastor-Pareja, J. C., Fernandez-Busnadiego, R.. 2021-04-14. Cryo-electron tomography of native Drosophila tissues vitrified by plunge freezing. https://doi.org/10.1101/2021.04.14.437159

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