Gautam Dey
Group Leader
Dey Group
EditThe Dey group investigates the evolution and diversity of mitosis using comparative cell biology and genomics in microbial eukaryotes across controlled and natural environments
Evolutionary cell biology of the nucleus
Group Leader
Dey Group
Edit(These web pages are updated infrequently.)
Our group at EMBL uses comparative quantitative cell biology, experimental evolution and evolutionary genomics across microbial eukaryotes, in both lab and natural environments, to investigate the evolution and diversity of cell division mechanisms. You will find a comprehensive list of our projects and collaborations here, and below some highlights from our recent and ongoing work.
Centromeres, the regions of eukaryotic chromosomes that are responsible for recruiting the mitotic and meiotic machinery during cell division, evolve much faster than the kinetochore that must bind them with high fidelity in order to promote chromosome segregation. This evolutionary interplay has dramatic impact upon chromosome number (Helsen et al. Nature Cell Biology 2024) and size variation and evolutionary dynamics at both centromere and kinetochore (Helsen et al. Nature 2026). This work is led by Jana Helsen and carried out in close collaboration with Gavin Sherlock (Stanford Genetics).
Mitotic nuclear remodelling mechanisms lie along a spectrum from ‘open’ (complete disassembly of the nuclear envelope in order to build the mitotic spindle) to ‘closed’ (intranuclear spindle associated with an intact nuclear envelope). We have shown recently that multinucleate life cycles (Dey et al. Current Biology 2026) promote the evolution of closed mitosis (Shah et al. Nature 2024), and are now shifting our attention to reconstructing NE dynamics in early eukaryotes as well as the evolutionary trajectories leading to the fully open mitoses of animals and land plants. Much of this work has been carried out in collaboration with Omaya Dudin (UNIGE) and Yannick Schwab (EMBL) and has been led within the group by Hiral Shah, Priyesh Parihar and Marie Jacobovitz.
Centrioles or basal bodies, that in animals form the core of the microtubule organising centre (MTOC) known as the centrosome, have been lost many times independently across eukaryotes. We are interested in the de novo evolution of centriole-independent MTOCs in these lineages, which includes many clades of algae as well as the close relatives of animals, the Ichthyosporea (Shah et al. Nature 2024). This work is led by Hiral Shah.
Using comparative approaches across multiple budding yeast and fission yeast species, we are interested in probing the evolutionary plasticity of NE (Dey et al. Nature 2020) and nucleolar remodelling, with a particular focus on the impact of stress and sexual reproduction on nuclear dynamics. This work is led by Ricardo Carvalho and Lisa Gubanova.
We leverage the power, resolution and throughput of expansion microscopy to profile ultrastructural diversity of the cytoskeleton and internal compartmentalisation of eukaryotes drawn from across the tree, including the remodelling that accompanies cell division. This is an ongoing long-term effort in partnership with Omaya Dudin (UNIGE), and in early work we have demonstrated the transformative power of the technique in eukaryotic microbiology (across more than 200 microbial eukaryotes, Mikus, Ramos, Shah et al. Cell 2025; in complex environmental samples, Flori, Mikus, Flaum et al. Current Biology 2025). This work was pioneered by Felix Mikus and Hiral Shah in the group and is now carried on by many in the lab.
We are funded by EMBL, an ERC Starting Grant (2023-2028), a FEBS Excellence Award (2024-2026), an EMBO Young Investigator Award (2025-2029) and the Gordon and Betty Moore Foundation (2025-2028)
As a postdoc, I discovered the mechanism by which fission yeast nuclei divide – a process that exhibits unexpected parallels to nuclear remodelling in animal cells (Dey et al., Nature 2020). We have also investigated the archaeal origins of the nucleus, using experimental models (Tarrason Risa et al., Science 2020; Pulschen et al., Current Biology 2020) and the proteomes of uncultured archaea (Dey et al., Trends Cell Biol 2016). My work suggested for the first time that deeply conserved mechanisms might unite nuclear remodelling strategies once thought to be distinct. During my PhD, I developed a novel phylogenetic method to detect protein co-evolution. This work revealed ancient, co-evolving modules in the human genome that we could study experimentally (Dey and Meyer, Cell Syst 2015; Dey et al., Cell Rep 2015).
