Form-function relationships in the development of Bacillus subtilis fruiting bodies

内孢子形成模式细菌枯草芽孢杆菌的自然分离株具有复杂的多细胞特征。与植物类似，枯草杆菌的孢子可以产生一个3D宏观的多细胞结构，产生更多的孢子--子实体。不同类型的细胞参与子实体及其亚结构的形成。在这个项目中，我们将研究细胞类型的特定功能如何支持生物膜皱纹的形成(“功能驱动形式”)以及大菌落结构如何影响孢子的产生(“形式驱动功能”)。在细胞型特异性荧光记者的帮助下，我们将在整个大菌落的水平上以及在其亚结构水平上一直到单个细胞(孢子)的水平上对过程进行成像。我们将开发基于深度学习的基于计算机的图像分析方法，以量化细胞状态在空间和时间上的转变。用这种方法--以及其他方法--我们将检验不同的假说，这些假说是关于通过对枯草杆菌进行定向遗传操作而形成子实体的。这将揭示这些遗传因素是否以及如何在多细胞发育过程中对新特性做出贡献。

Natural isolates of the endospore-forming model bacterium Bacillus subtilis show complex multicellular traits. Similar to plants, out of a spore of B. subtilis a 3D macroscopic multicellular structure can emerge that produces many more spores - a fruiting body. Different cell types partake in the formation of a fruiting body and its substructures. In this project, we will study how cell-type specific functions support the formation of biofilm wrinkles (“function drives form”) and how macrocolony architecture affects the production of spores (“form drives function”). With the help of cell-type specific fluorescent reporters we will image processes at the level of the entire macrocolony and at the level of its substructures down to individual cells (spores). We will develop computer-based image analysis methods based on deep learning in order to quantify cellular state transitions in space and time. With this approach – and other methods - we will test different hypotheses regarding the formation of fruiting bodies by targeted genetic manipulations of B. subtilis. This will reveal whether and how these genetic elements contribute to emergent properties during multicellular development.