Project description DEENESFRITPL Understanding the dual spindle assembly phenomenon in mammalian zygotes During the first embryonic division, mammalian zygotes initially form two bipolar spindles of the maternal and paternal chromosomes. The many aspects of dual spindle assembly and function are still unknown, including the question about the contribution of cytoplasmic and chromosomal microtubule nucleation to the spindle’s formation and cases of error-prone alignment. The EU-funded DualSpindleAssembly project aims to discover the mechanism and function of dual spindle assembly, using light-sheet microscopy, computational image analysis and molecular perturbations. High-resolution 4D imaging of live mouse zygotes will allow the tracking of individual nucleation sites and microtubule tips. This will create the first spatial map of microtubule nucleation and help to decipher the role of the two microtubule populations in dual spindle assembly. Show the project objective Hide the project objective Objective The first embryonic division after fertilization is essential for development of the organism and has to promote the union of the parental genomes. My host lab recently showed that in mammalian zygotes two bipolar spindles form, which first independently congress the maternal and paternal chromosomes and then must be aligned in parallel for a faithful division. The novel dual spindle assembly provided a likely rationale for erroneous divisions into more than two blastomeric nuclei observed in human fertility treatment. Indeed, preventing the alignment of the two spindles gives rise to multi-nucleated two-cell embryos also in mice. Due to its recent discovery and the difficulty of imaging in the light sensitive zygote, dual spindle assembly and function remains elusive. It is for example unclear what the contribution of cytoplasmic versus chromosomal microtubule (MT) nucleation is for forming two spindles and why spindle alignment is error-prone and variable between different mammals. Recent advances in microscopy in my host lab now enable me to address these questions. In my project, I will dissect the mechanism of dual spindle assembly and function by combining light sheet microscopy, computational image analysis, and molecular perturbation. To achieve this, I will perform 4D imaging of live mouse zygotes at high resolution that allows me to track individual nucleation sites as well as MT tips. This will allow me to generate the first spatial map of MT nucleation and assess what the contribution of the two MT populations for dual spindle assembly is. Moreover, I will test which MT nucleation pathway is essential for dual spindle assembly by molecular perturbations. Finally, I will check if errors in spindle alignment are the cause of parental genome loss, by identifying the key alignment factors and validate them in model organisms with different alignment fidelities. Thus, my studies will improve our understanding of cell division in mammals and human infertility. Fields of science social sciencessociologydemographyfertilitynatural sciencesphysical sciencesopticsmicroscopynatural sciencesbiological scienceszoologymammalogynatural sciencesbiological sciencesgeneticschromosomesnatural sciencesbiological sciencesgeneticsgenomes Programme(s) H2020-EU.1.3. - EXCELLENT SCIENCE - Marie Skłodowska-Curie Actions Main Programme H2020-EU.1.3.2. - Nurturing excellence by means of cross-border and cross-sector mobility Topic(s) MSCA-IF-2020 - Individual Fellowships Call for proposal H2020-MSCA-IF-2020 See other projects for this call Funding Scheme MSCA-IF-EF-ST - Standard EF Coordinator EUROPEAN MOLECULAR BIOLOGY LABORATORY Net EU contribution € 174 806,40 Address Meyerhofstrasse 1 69117 Heidelberg Germany See on map Region Baden-Württemberg Karlsruhe Heidelberg, Stadtkreis Activity type Research Organisations Links Contact the organisation Opens in new window Website Opens in new window Participation in EU R&I programmes Opens in new window HORIZON collaboration network Opens in new window Other funding € 0,00
