Drei-dimensionale Rekonstruktion der Zelltrennung: die Rolle ESCRT-abhängiger Filamente
Strukturbiologie
Zusammenfassung der Projektergebnisse
In conclusion, from our quantitative analyses it is clear that the pole-to-pole distance is scaling over the course of embryonic development, while the chromosome-tochromosome distance is not. For models on the segregation of mitotic chromosomes, our results put an important emphasis on the role of the mid spindle in partitioning the chromatids to the daughter cells. Our results are consistent with our previous findings, showing that a double-laser-cut mid spindle (i.e., a mid spindle detached from the spindle poles) in the early 1-cell embryo is sufficient to drive chromosome segregation. Currently, we are performing such laser-cut experiments in 2-, 4-, 8, and 16-cell C. elegans embryos. It is unclear at this point, however, which factors set the final mid spindle length in big and also in small embryonic cells in C. elegans. It is our long-term goal to develop a biophysical model of spindle scaling for the C. elegans embryo during mitosis. Such a model will be developed together with our collaborators. In addition, we will also explore the role of the cell geometry on chromosome segregation, as this can be analyzed in our LLSFM data. This important aspect is largely unexplored so far. In the future, we will also apply large-scale electron tomography to analyze spindle organization in multi-cell embryos. By combining data on the dynamics and the ultrastructure of spindles we aim to even deeper understand mitotic cell division in one of the major model systems in current cell biology.
