| Abstract: |
| In early development, embryo cells can opt to divide asymmetrically and produce daughters that have distinct fates. At the cell scale, asymmetric division is achieved with the help of exquisitely fine-tuned mechanistic processes that control the location of the cell division plane. In this talk we will introduce two mechanisms for how a dividing cell might achieve asymmetric division. First, we start with the simple single cell bacteria, Caulobacter Crescentus and show how a single cell employs spatio-temporal protein localization patterns to estimate the location of the division site. Using advection-reaction-diffusion PDE models we show how modulation of ATP-ase reaction rates can affect the spatial location of several proteins and transition the cell from a symmetric to an asymmetric division program. We also show how Brownian dynamics simulations can be used to verify some of the conclusions of the PDE models. A second example of how asymmetric division is achieved will be illustrated in the early stages of C. elegans embryo division. In this case, the cell employs more complicated biopolymer networks to achieve proper asymmetric division plane placement. We use stochastic models and experimental data to show how division plane placement can be controlled robustly. In both cases, model results will be compared with data and general mechanisms for division plane placement will be discussed. |
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