RT Journal Article SR Electronic T1 Label free 3D analysis of organelles in living cells by refractive index shows pre-mitotic organelle spinning in mammalian stem cells JF bioRxiv FD Cold Spring Harbor Laboratory SP 407239 DO 10.1101/407239 A1 Patrick A. Sandoz A1 Christopher Tremblay A1 Sebastien Equis A1 Sorin Pop A1 Lisa Pollaro A1 Yann Cotte A1 F. Gisou van der Goot A1 Mathieu Frechin YR 2018 UL http://biorxiv.org/content/early/2018/09/04/407239.abstract AB Holo-tomographic microscopy (HTM) is a label-free non-phototoxic microscopy method reporting the fine changes of a cell’s refractive indexes (RI) in 3D. By combining HTM with epifluorescence, we demonstrate that cellular organelles such as Lipid droplets and mitochondria show a specific RI signature that distinguishes them with high resolution and contrast. We further show that HTM allows to follow in unprecedented ways the dynamics of mitochondria, lipid droplets as well as that of endocytic structures in live cells over long period of time, which led us to observe to our knowledge for the first time a global organelle spinning occurring before mitosis.