June 16 & 17
Developed nations are currently facing the problem of late motherhood and the associated decline in fertility. Declining fertility leads to demographic decline, which will have unprecedented consequences for our societies in the near future. There is a significant drop in female fertility after the age of 35. In industrialized countries, maternal age at first birth is rising rapidly. Furthermore, worldwide data show that over 25% of female fertility problems are unexplained, indicating a huge gap in our understanding of female reproduction. Poor oocyte quality is at the root of the majority of female fertility problems. Oocytes are formed before birth, and remain dormant in the ovary for several decades, from birth to menopause. Despite their remarkable longevity, oocytes age with advanced maternal age. Little is known about the strategies and mechanisms that enable oocytes to escape aging for many years, or why these mechanisms eventually fail after the age of 35. The French government has commissioned a major investigation, culminating in the publication in 2021 of a report on the causes of infertility in France and a mandate given to INSERM to coordinate a national program to promote research into women’s infertility in 2022. We therefore believe that it is timely to organize a meeting supported by the Fondation Singer-Polignac on this important and topical subject of oocyte biology.
Monday 16th June 2025
First Session: From Soma to Germline: oocyte dormancy establishment
Chair: Elvan Böke
Jasmin Rettkowski (ETH Zurich): Stem Cells dormancy
Katsuhiko Hayashi (Osaka University, Japan): Germ Stem Cells culture to produce oocytes
Jean-René Huynh (CIRB, France): Evolutionary Adaptations to Cellular Constraints in Meiotic Chromosome Pairing
Second Session: Establishing Maternal Reserves
Chair: Marie-Hélène Verlhac
Yaniv Elkouby (The Hebrew University of Jerusalem, Israël): Divisions of the germline cyst in Zebrafish
Petr Svoboda (Institute of Molecular Genetics, Praha): Small RNAs in oocytes
Geraldine Seydoux (Johns Hopkins School of Medicine, USA): Cytoplasm RNA dynamics in c. elegans
Arnaud Hubstenberger (IBV, France): Phase Separation of RNPs in c. elegans
Florence Marlow (Icahn School of Medicine at Mount Sinai, USA): Oocyte polarity
Short Talks selected on abstracts
Avishag Mytlis, Hebrew university of Jerusalem (on Zoom): The Zygotene Cilium Regulates Meiosis, Germ Cell Development, and Fertility in Zebrafish, Mice, and Humans
Karin Levy, Hebrew university of Jerusalem: Coordination of meiosis by nuclear-dependent Plk1 centrosome regulation co-organizes oocyte cellular compartments
Stephanie Rosswag de Souza, CRG Barcelona: Unraveling unique features of transcription and translation in oocytes
Anahi Molla-Herman, CIRB Collège de France: H2Av controls genome integrity and fertility in Drosophila female germline
Noemi Zollo, CIRB Collège de France: A novel RNP compartment boosts translation in growing mouse oocytes to avoid cytoplasm dilution
Antoine Guichet, IJM Paris: A dual system involving the nuclear envelope and membrane cortex ensures that the nucleus is anchored asymmetrically in the Drosophila oocyte
Yamiini Vadapalli, Max Planck Institute for Multidisciplinary Sciences: Actin and microtubules cooperate in chromosome capture during oocyte meiosis
Andrea Pauli (IMP, Austria): Life’s first kiss – what do we miss?
Tuesday 17th June 2025
Third Session: Preserving maternal stores via asymmetric divisions
Chair: Jean-René Huynh
Eva Hoffmann (University of Copenhagen, Denmark): Oocyte aneuploïdy
Karen Schindler (University of Rutgers, USA): Oocyte acentriolar Spindle Assembly
Michaël Lampson (University of Pennsylvania, USA): Meiotic drive during oocyte divisions
1:00 to 2:00 pm lunch break
Carl-Philip Heisenberg (ISTA, Austria): Establishing oocyte polarity
Marie-Emilie Terret (CIRB, France): Biophysics of oocyte divisions
Short Talks selected on abstracts
Katja Wassmann, IJM Paris: Coordinating Chromosome Segregation with Cell Cycle Progression in Oocyte Meiosis
Thierry Lorca, CRBM Montpellier: Role of Gwl in regulating both Erp1 stabilization and Cdk1-APC/C activities, ensuring proper meiotic progression.
Tommaso Cavazza, University of Zurich: Parental genome unification is error prone in mammalian embryos
Christopher Thomas, IBDM Marseille: Revealing the Secrets of Ovulation
Marzia Munafo, EMBL Rome: Precision genetic perturbations reveal the functional role of chromatin marks in oogenesis and inheritance
Rose Bulteau, CIRB Collège de France: Atomic Force Microscopy reveals differences in mechanical properties linked to cortical structure in mouse and human oocytes
Volodymyr Porokh, Masaryk University, Faculty of Medicine: Zygotic spindle orientation – biparental contribution to genetic stability
Melina Schuh (Max Planck, Germany): Mammalian oocyte divisions
Biographies – organizers
Elvan Böke
Elvan Böke completed her PhD training at the Cancer Research UK Manchester Institute (2008-2012) on cell division, followed by a postdoctoral training at Harvard Medical School in Boston, USA (2013-2016) on cytoplasmic organization. In 2017, she established her laboratory at CRG, Barcelona. Elvan has received numerous honors, including two consecutive European Research Council Grants (Starting in 2017 and Consolidator in 2022), an EMBO Young Investigator Award in 2021, and the EMBO Gold Medal in 2024. Her research focuses on the strategies and mechanisms that allow oocytes to evade ageing for decades, and why these strategies eventually fail with advanced maternal age.
Marie-Hélène Verlhac
Marie-Hélène Verlhac, student from ENS de Lyon, started her PhD in Prof Hugh Clarke’s lab at Mc Gill University and finished it at the Jacques Monod Institute with Bernard Maro. After a post-doc with Prof Rik Derynck at UCSF, she was recruited to the CNRS and started her own lab. Her lab, that she now co-heads with Marie-Emilie Terret, is currently at the CIRB, at the Collège de France. She is also heading the CIRB.
She studies the maternal heritage transmitted by the female gamete to her offspring. At fertilization, the female gamete transmits not only its haploid genome but also its enormous cytoplasm containing the reserves necessary for the formation of the embryo. She pioneered the field of acentrosomal spindle assembly and positioning of in mouse oocytes. Her team has discovered original mechanisms, based on purely biophysical phenomena, controlling the nature and preservation of maternal inheritance. Her work has been acknowledged by prizes and recognitions such as for example the EMBO membership, the CNRS Silver medal, the Albert Brachet embryology Prize from the Belgium Royal Academy of Sciences, the Jaffe Prize from the French academy of Sciences and she was appointed Knight from the French national order of the Legion d’honneur.
Biographies – speakers
Prof. Yaniv M. Elkouby
Prof. Yaniv M. Elkouby is a professor in the Department of Developmental Biology at the Hebrew University of Jerusalem School of Medicine. Yaniv received his PhD from the Technion in 2010, under the supervision of Dale Frank, where he studied early embryonic development. In 2011, Yaniv joined the lab of Mary Mullins at the University of Pennsylvania for his postdoctoral studies, where he established the zebrafish ovary as a new model system to study the cellular mechanisms of ovary development and early egg production.
In late 2017 Yaniv established his own lab in the Hebrew University of Jerusalem. His research employs a multidisciplinary holistic approach to the developing ovary, and he pioneered the view of egg production by advanced quantitative and live microscopy of whole ovaries. By contributing to our understanding of the earliest stages of egg production, his studies generate knowledge that is directly relevant to human reproduction. Major accomplishemnts from his lab include the discovery of the oocyte zygotene cilium, identifying the oocyte symmetry-breaking mechanism, deciphering the formation of a conserved membraneless organelle in oocytes through molecular condensation, characterizing the germline cyst, and uncovering novel regulators of zebrafish germ cell and gonad development. The ultimate goal of the Elkouby lab is to continue and make important discoveries by illuminating unpredicted cellular machineries in germ cell production, gonad development, and reproduction.
Funding and support for his research have included ISF, ISF-NRF, BSF, DFG, Israel Innovation Authority, and ERC Consolidator grants, and the ZCAI Prize for Discovery in Medical Research, and in 2023, Yaniv became an EMBO Young Investigator (YIP). Prof. Elkouby serves an elected board member of the Israeli Society of Developmental Biology.
Petr Svoboda
Petr Svoboda received his Ph.D. in 2002 at the University of Pennsylvania where he studied mammalian RNA interference (RNAi) in the lab of Richard Schultz. He did then a postdoc with Witek Filipowicz at the Friedrich Miescher Institute in Basel (2003-2006 ), mainly working on mammalian microRNA. Since 2007 he is a groupleader at the Institute of Molecular Genetics of the Czech Academy of Sciences. His lab has been studying RNA metabolism during oocyte-to-zygote transition. In the last decade, his primary research interest focused on biology of mammalian small RNA pathways in the germline and soma. This included studies of regulation of the microRNA pathway in oocytes, biological roles of the piRNA pathways in rodents, and molecular mechanisms enhancing RNAi activity in mammalian cells. In 2018, he became a full professor in cell & developmental biology at the Charles University in Prague and was elected an EMBO member in 2018.
Jasmin Rettkowski
Jasmin Rettkowski is a postdoctoral researcher in the Laboratory of Stem Cell Biology and Ageing at ETH Zurich, led by Prof. Nina Cabezas-Wallscheid. She studied Molecular Biomedicine at the University of Münster and the Karolinska Institute in Stockholm before joining the Max Planck Institute of Immunobiology and Epigenetics in Freiburg. She received her PhD in Molecular Medicine, investigating the modulation of hematopoietic stem cell quiescence and dormancy as a therapeutic strategy for myocardial infarction. Her research centres on the metabolic and molecular regulation of hematopoietic stem cells, with a focus on ageing, cardiac regeneration and translational stem cell medicine.
Michael Lampson
Michael Lampson studied physics as an undergraduate at Harvard University, physiology and biophysics as a graduate student at Cornell University, and chemical and cell biology as a postdoctoral fellow at the Rockefeller University. He is currently a professor of biology at the University of Pennsylvania, where his lab pursues a variety of questions related to chromosomes, the cell cycle, and cell division using various model systems. Topics include mechanisms that ensure accurate chromosome segregation in mitotic and meiotic cell divisions, centromere inheritance and function in the mammalian germline, and the cell biology of meiotic drive, in which centromeres act as selfish genetic elements in female meiosis. His lab has also developed tools that enable innovative experimental approaches, such as FRET-based biosensors for mitotic kinases and photocaged chemical inducers of protein dimerization for optogenetic control of protein localization. Working with multiple collaborators at Penn, his research program spans mechanistic cell biology, chemical biology, mouse models for reproductive biology, and molecular evolution.
Marie-Emilie Terret
Marie-Emilie Terret, is a researcher in cell biology, who studies the formation of oocytes in mammals. The goal of her team “Oocyte mechanics and morphogenesis”, that she co-directs with Marie-Hélène Verlhac at the CIRB, Collège de France, is to understand how an oocyte transforms into a viable embryo, using biophysical approaches to meiotic divisions in a highly interdisciplinary and collaborative context.
Dr. Karen Schindler
Dr. Karen Schindler is a Professor in the Department of Genetics at Rutgers University, New Jersey. She received a B.S. in Biology from Loyola University, Maryland and a Ph.D. in Biochemistry/Molecular Biology at Thomas Jefferson University. She then completed postdoctoral training with Dr. Richard Schultz at the University of Pennsylvania. Her laboratory investigates the mechanisms by which the Aurora protein kinases regulate chromosome segregation during meiosis, is probing the genetics of female infertility in humans, and is seeking to understand how Sirtuin 7 functions control reproductive longevity. Dr. Schindler was the recipient of 2018 SSR Virendra B. Mahesh New Investigator Award and the 2020 FASEB Excellence in Science Early Career Investigator Award. Dr. Schindler is currently co-editor in chief of the Reproduction journal and director of the Gametogenesis and Embryogenesis section of the Frontiers in Reproduction course.
Jean-René Huynh
Jean-René Huynh is a CNRS Director of Research and a group leader specializing in the evolution and development of germ cells. He holds a PhD in Genetics from the University of Cambridge, obtained under the supervision of Dr. Daniel St Johnston. He previously served as a junior and then senior group leader in the Department of Genetics and Developmental Biology at Institut Curie, where his lab focused on germline stem cell biology and the initiation of meiosis during Drosophila oogenesis. In 2018, he relocated his lab to the Collège de France, broadening the scope of his research to investigate germline cell differentiation in species such as the medaka fish, the jellyfish Clytia hemisphaerica, and more recently, various nematodes with diverse reproductive strategies. Dr. Huynh has received numerous awards, including the CNRS Bronze Medal and the 2023 « Grandes Avancées Française en Biologie » prize awarded by the French Academy of Sciences. A recognized expert in his field, he serves as an editor for PLoS Genetics and participates as a panel member for several scientific funding agencies.
Dr. Geraldine Seydoux
Dr. Geraldine Seydoux’s research focuses on the development of the germline. Her lab characterized identified global inhibition of mRNA transcription as an essential first step to establish the embryonic germline and characterized post-transcriptional mechanisms of gene regulation that promote germ cell fate and differentiation. Most recently, her lab described a family of intrinsically-disordered proteins that stabilize RNA granules in germ cells by functioning as surface-tension reducing agents (Pickering agents), the first demonstration of this type of activity in cells.
Florence Marlow
For over two decades, I have leveraged the zebrafish system in my research. As a graduate student at Vanderbilt University, I studied cell polarization during gastrulation, focusing on cellular and genetic regulation of moving cells. As a Damon Runyon Cancer Research Foundation fellow at the University of Pennsylvania, I investigated oocyte polarity and maternal regulation of embryonic development. I was a primary supervisor of a comprehensive four-generation maternal-effect and ovary screen to identify essential vertebrate genes for early development and fertility. My current research applies molecular, genetic, cell biological, and biochemical methods to understand:
- Mechanisms establishing and maintaining the ovarian reserve and germline stem cells
- Cellular polarity mechanisms and their role in oocyte longevity and reproductive aging
- Mitigating mechanisms of reproductive aging
- Cellular and molecular interactions between reproductive systems, immune, and nervous systems
I have maintained continuous NIH funding throughout my sixteen years as a principal investigator, recently receiving an R35 award and demonstrating strong scholarly, teaching, and service track records.
In academic leadership, I have served as Associate Director of the MSTP program for 3 years and co-director of the Development, Regeneration, and Stem Cells (DRS) graduate training area at ISMMS for seven years. My responsibilities included:
- Advising first-year students and monitoring their progress toward achieving academic milestones
- Organizing orientation and program events
- Recruiting diverse students
- Serving as a liaison between graduate leadership, faculty, and students to establish and achieve the academic and training missions of the graduate program
- Serving on academic affairs, and curriculum committees, and chairing thesis advisory meetings and exams
I have successfully mentored PhD, MSTP, and master’s students, who are now pursuing careers in science, research, and medicine. I have also supported postdoctoral researchers transitioning to academic and industry positions. As part of my commitment to scientific outreach, I serve as scientific director of BioEYEs NYC, a K-12 program that introduces zebrafish, genetics, and scientific opportunities to underserved schools.
Eva Hoffmann
Eva Hoffmann is professor of molecular genetics and Head of Department of the Department of Cellular and Molecular Medicine at the Faculty of Health and Medical Sciences, University of Copenhagen, Denmark. Her lab focusses on exploring the molecular mechanisms that govern genomic diversity in human germ cells and embryos and their implications for reproductive phenotypes and congenital disorders.
Prof. Hoffmann obtained her PhD in Biochemistry for University of Oxford and held research fellowships from EMBO as well as the Royal Society and Medical Research Council in the UK from 2005-2015 as principle investigator at the MRC Genome Damage and Stability Centre. In 2016, she relocated to the Danish National Research Foundation (DNRF) Center for Chromosome Stability at the University of Copenhagen Medical School. She is currently a Novo Nordisk Foundation Distinguished Investigator and Direct-elect of a Center for Fertility and Inheritance funded by the Danish National Research Foundation.
Prof. Hoffmann is an elected member of the European Molecular Biology Organization (EMBO), and serves on the Executive Board and as Scientific Coordinator of ReproUnion.
Carl-Philipp Heisenberg
Carl-Philipp Heisenberg (born 1968) is a developmental biologist who studied biology at the Ludwig-Maximilians-University in Munich and completed his doctorate in the group of Nobel laureate Christiane Nüsslein-Volhard at the Max-Planck-Institute for developmental biology in Tübingen in 1997. In 2001, he became research group leader and Emmy Noether Junior Professor at the Max-Planck-Institute for Molecular Cell Biology and Genetics in Dresden. In 2010, he started as a Professor at the Institute of Science and Technology (IST) Austria in Klosterneuburg. Heisenberg received an ERC Advanced Grant in 2017 from the European Research Council and, in the same year, the “Würdigungspreis” from Lower Austria. Since 2015 he has been a member of the German Academy of Sciences Leopoldina. In 2018, he joined the Board of Reviewing Editors of the journal Science and, in 2019, received the Carus Medal from the Leopoldina.
Andrea Pauli
Andrea Pauli (Andi) studied biochemistry in Regensburg, Germany, and obtained her Masters in Molecular and Cellular Biology from Heidelberg University, Germany. In 2004, she started her PhD at the Research Institute of Molecular Pathology (IMP) in Vienna, Austria, co-supervised by Kim Nasmyth and Barry Dickson to investigate non-mitotic functions of cohesin using Drosophila as a model organism. In 2006, she moved with Kim Nasmyth to Oxford University, UK, where she obtained her PhD in 2009, providing the first direct evidence that cohesin has essential functions in post-mitotic cells. As a postdoc in Alex Schier’s lab at Harvard University, USA, Andi made two key findings that have shaped her research since: first, translation is widespread outside of protein-coding regions in vertebrates; and second, some of the newly discovered translated regions encode functionally important short proteins, one of which is Toddler, an essential signal for mesodermal cell migration during gastrulation.
In 2015, Andi established her own lab at the IMP in Vienna, Austria, which aims to gain mechanistic insights into (1) the fundamental yet still poorly understood process of fertilization in vertebrates and (2) translational and proteome-wide rewiring during the egg-to-embryo transition and more generally during cellular and organismal dormancy. The long-term vision of the Pauli lab is to unravel new concepts and molecular mechanisms governing key developmental transitions that mark the beginning of life.
Andi’s work has been funded by the ERC, EMBO, HFSP, the NIH grant to independence (K99), the FWF START Prize, and a Whitman Center Fellowship from the Marine Biological Labs. In 2018, Andi became an EMBO Young Investigator (EMBO YIP), and in 2021 she was elected as an EMBO Member. In 2022, Andi got promoted to a senior group leader (= tenure) at the IMP.
Arnaud Hubstenberger
Arnaud Hubstenberger became interested in the post-transcriptional control of germline development during his first post-doc in Tom Evans’ team in Colorado. There, he introduced phase transitions as a framework to study the supra-molecular organization of the transcriptome in the oocyte (Hubstenberger et al., 2013). During a second post-doctorate in Dominque Weil’s team at the Institut Biology Paris Seine, he developed a cutting edge FAPS method to purify RNA condensates, unravelling how the translation of RNA regulons is coordinated transcriptome-wide (Hubstenberger et al., 2017). In 2018, after joining the CNRS as researcher, he initiated an ATIP-AVENIR team at the Insitute of Bioogy Valrose in Nice, focusing on how the multiscale multiphase organization of the transcriptome control germline development (Cardona et al., 2023).
Melina Schuh
Melina Schuh is a Director at the Max-Planck-Institute for Multidisciplinary Sciences in Göttingen, Germany, where she leads the Department of Meiosis. She graduated in Biochemistry from the University of Bayreuth in 2004, working on centromeres in Drosophila embryos with Stefan Heidmann and Christian F. Lehner. In 2008, she obtained her PhD from the University of Heidelberg and the European Molecular Biology Laboratory (EMBL), where she established methods for high-resolution microscopy of live mouse oocytes in the group of Jan Ellenberg. In 2009, she became a Group Leader at the MRC Laboratory of Molecular Biology (LMB). At the LMB, her group carried out the first studies of meiosis in live human oocytes and developed strategies for high-content screens for meiotic genes in mammals. In 2016, she was appointed as Director at the Max Planck Institute for Biophysical Chemistry. In 2022, the Institute fused with the Max Planck Institute for Experimental Medicine into the Max Planck Institute for Multidisciplinary Sciences. Her laboratory studies how errors arise during the meiotic divisions of mammalian eggs, and what causes the age-related decline in female fertility. Her lab also developed a new method for the acute degradation of endogenous proteins, called Trim-Away. Recent work from her lab established essential functions for actin and a liquid-like spindle domain in acentrosomal spindle assembly, and revealed the cause of spindle instability in human oocytes. She also recently discovered how mRNAs and proteins are stored in oocytes for the early embryo. Melina Schuh is a member of the Leopoldina (German National Academy of Sciences), an EMBO member and a recipient of the Leibniz Prize, the EMBO Gold Medal, the Colworth Medal, an ERC Starting Grant, a Biochemical Society Early Career Award, the European Young Investigator Award, the Lister Research Prize, the John Kendrew Young Scientist Award, and the Binder Innovation Prize.
Katsuhiko Hayashi
Katsuhiko Hayashi, a full professor in Department of Genome Biology, Graduate School of Medicine, Osaka University, is working on germ cell development and its reconstitution in vitro through his career: 1994-1996, MS course of Meiji University; 1996-2002, an assistant professor in Tokyo University of Science; 2002-2005, a staff researcher in Osaka Medical Center (Ph.D. 2004); 2005-2009, post-doctoral fellow in the Gurdon Institute, University of Cambridge; 2009-2014, associate professor in Kyoto University; and 2014-2021 a full professor in Kyushu University. From 2021, He has been in the current position in Osaka University. The research aim of the Hayashi’s group is to understand genetic and epigenetic regulation of mammalian oocyte differentiation using a unique culture system that produces oocytes from pluripotent stem cells.
