Team
Team manager: Merdes Andreas
Presentation
Work in our group focuses on the proteins of the centrosome, and on their role in nucleation and organization of microtubules. We try to understand how microtubules are formed from and how they are anchored at the centrosome. Because the centrosome loses its function as a microtubule-organizing center in many differentiated cell types, and because centrosome proteins re-localize to novel sites of microtubule organization, we study the underlying mechanisms in two cellular models, skin keratinocytes and osteoclasts.
Project 1
In epidermal keratinocytes, centrosome-dependent microtubule organization is lost, and a subset of microtubules is reorganized at the cell cortex (arrows). A section of mouse skin is visualized after expansion microscopy. Red: microtubules, green: desmosomes. Bar, 2.5 μm.
Project 2
Osteoclasts are syncytia that form by fusion of precursor cells. Centrosomes (arrowheads) are clustered in small areas, but this clustering is lost in osteoclasts from ninein-knockout mice, leading to an unfocused microtubule network. Ninein-knockout mice show premature ossification early during development. Red: centrosomes, blue: nuclei, green: microtubules. Bar, 10 μm.
– Gilbert T, Gorlt C, Barbier M, Duployer B, Plozza M, Dufrancais O, Martet LE, Dalbard E, Segot L, Tenailleau C, Haren L, Vérollet C, Bierkamp C, Merdes A. 2024. Loss of ninein interferes with osteoclast formation and causes premature ossification. Elife. 13:e93457. doi: 10.7554/eLife.93457.
– Haren L, Farache D, Emorine L, Merdes A. 2020. A stable sub-complex between GCP4, GCP5 and GCP6 promotes the assembly of γ-tubulin ring complexes. J Cell Sci. 133:jcs244368. doi: 10.1242/jcs.244368.
– Lecland N, Hsu CY, Chemin C, Merdes A, Bierkamp C. 2019. Epidermal development requires ninein for spindle orientation and cortical microtubule organization. Life Sci Alliance. 2:e201900373. doi: 10.26508/lsa.201900373.
– Espigat-Georger A, Dyachuk V, Chemin C, Emorine L, Merdes A. 2016. Nuclear alignment in myotubes requires centrosome proteins recruited by nesprin-1. J Cell Sci. 129:4227-4237. doi: 10.1242/jcs.191767.
– Guillet V, Knibiehler M, Gregory-Pauron L, Remy MH, Chemin C, Raynaud-Messina B, Bon C, Kollman JM, Agard DA, Merdes A, Mourey L. 2011. Crystal structure of γ-tubulin complex protein GCP4 provides insight into microtubule nucleation. Nat Struct Mol Biol. 18:915-9. doi: 10.1038/nsmb.2083.
