Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, CT, 06520, USA.
Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
Nat Commun. 2018 Jun 5;9(1):2177. doi: 10.1038/s41467-018-04539-4.
Collective behavior can spontaneously emerge when individuals follow common rules of interaction. However, the behavior of each individual differs due to existing genetic and non-genetic variation within the population. It remains unclear how this individuality is managed to achieve collective behavior. We quantify individuality in bands of clonal Escherichia coli cells that migrate collectively along a channel by following a self-generated gradient of attractant. We discover that despite substantial differences in individual chemotactic abilities, the cells are able to migrate as a coherent group by spontaneously sorting themselves within the moving band. This sorting mechanism ensures that differences between individual chemotactic abilities are compensated by differences in the local steepness of the traveling gradient each individual must navigate, and determines the minimum performance required to travel with the band. By resolving conflicts between individuality and collective migration, this mechanism enables populations to maintain advantageous diversity while on the move.
当个体遵循共同的相互作用规则时，集体行为可以自发出现。然而，由于种群内存在遗传和非遗传变异，每个个体的行为都有所不同。目前尚不清楚如何管理这种个体差异以实现集体行为。我们通过在通道中沿着自身产生的趋化剂梯度追踪来量化克隆大肠杆菌细胞在集体迁移时的个体差异。我们发现，尽管个体趋化能力存在很大差异，但细胞仍能够通过在移动带内自发分类来作为一个连贯的整体进行迁移。这种分类机制确保了个体趋化能力的差异通过每个个体必须导航的移动梯度的局部陡峭程度的差异得到补偿，并确定了与带一起迁移所需的最低性能。通过解决个体性和集体迁移之间的冲突，这种机制使种群能够在迁移过程中保持有利的多样性。
