Lénárt, Peter, Dr.

Research Group Leader and Head of Live-cell Imaging Facility at the MPI-NAT

since 2018 Research Group Leader and Head of Live-cell Imaging Facility, Max-Planck Institute for Biophysical Chemistry, Göttingen, Germany
2011 - 2018 Group Leader, European Molecular Biology Laboratory, Heidelberg, Germany
2008 - 2011 Staff Scientist, European Molecular Biology Laboratory, Heidelberg, Germany
2005 - 2008 Postdoctoral fellow, Laboratory of Jan-Michael Peters, Institute of Molecular Pathology, Vienna, Austria
2000 - 2005 PhD Student, Laboratory of Jan Ellenberg, European Molecular Biology Laboratory, Heidelberg, Germany
1995 - 2000 Diploma in Biology, Eötvös Loránd University, Budapest, Hungary

Major Research Interests
Oocyte meiosis is a form of cell division specialized to produce the fertilizable egg. Our main interest is understanding how the cell division machinery, the cytoskeleton in particular, adapted to carry out these specialized divisions. For example, oocytes are exceptionally large cells storing nutrients for the embryo that divide very asymmetrically in order to retain these nutrients in a single egg cell. How does the cytoskeleton support divisions in this extreme geometry? Indeed, we showed that, compared to mitosis of small somatic cells, additional, meiosis-specific mechanisms are required. Interestingly, we found that while in somatic cells microtubules dominate, in the oocyte key functions are taken over by the actin cytoskeleton; for example, an actin net transports chromosomes to the forming spindle and actin is also involved in regulating spindle assembly. To explore the conservation and diversity of these meiosis-specific functions, we are using marine model species such as the oocytes of starfish. These oocytes are highly transparent, exceptionally resistant to light and easy to handle, rendering them an excellent model for live cell microscopy. In our future work we aim to further establish these marine models by developing advanced imaging assays and tools for targeted molecular perturbations. In turn we will use these tools to further dissect mechanisms of meiotic divisions. Studying oocyte meiosis is important, as a euploid egg is at the origin of life of any healthy animal and human individual, while the mechanisms are still poorly understood. In addition, understanding how cell division adapted and diversified to such specialized functions will reveal general principles of cellular organization.

Homepage Department/Research Group
https://www.mpinat.mpg.de/de/lenart

Selected Recent Publications

Wesolowska N, Avilov I, Machado P, Geiss C, Kondo H, Mori M, Lenart P (2020) Actin assembly ruptures the nuclear envelope by prying the lamina away from nuclear pores and nuclear membranes in starfish oocytes. Elife 9: e49774

Burdyniuk M, Callegari A, Mori M, Nedelec F, Lenart P (2018) F-Actin nucleated on chromosomes coordinates their capture by microtubules in oocyte meiosis. The Journal of cell biology 217:2661-2674. doi:10.1083/jcb.201802080

Bun P, Dmitrieff S, Belmonte JM, Nedelec FJ, Lenart P (2018) A disassembly-driven mechanism explains F-actin-mediated chromosome transport in starfish oocytes. eLife 7. doi:10.7554/eLife.31469

Bischof J, Brand CA, Somogyi K, Majer I, Thome S, Mori M, Schwarz US, Lenart P (2017) A cdk1 gradient guides surface contraction waves in oocytes. Nature communications 8:849. doi:10.1038/s41467-017-00979-6

Borrego-Pinto J, Somogyi K, Karreman MA, Konig J, Muller-Reichert T, Bettencourt-Dias M, Gonczy P, Schwab Y, Lenart P (2016) Distinct mechanisms eliminate mother and daughter centrioles in meiosis of starfish oocytes. The Journal of cell biology 212:815-827. doi:10.1083/jcb.201510083