Supplementary information files for Motility and self-organization of gliding Chlamydomonas populations

Supplementary files for article Motility and self-organization of gliding Chlamydomonas populations Cellular appendages such as cilia and flagella represent universal tools enabling cells and microbes, among other essential functionalities, to propel themselves in diverse environments. In its planktonic, i.e., freely swimming, state the unicellular biflagellated microbe Chlamydomonas reinhardtii employs a periodic breaststroke-like flagellar beating to displace the surrounding fluid. Another flagella-mediated motility mode is observed for surface-associated Chlamydomonas cells, which glide along the surface by means of force transduction through an intraflagellar transport machinery. Experiments and statistical motility analysis demonstrate that this gliding motility enhances clustering and supports self-organization of Chlamydomonas populations. We employ Minkowski functionals to characterize the spatiotemporal organization of the surface-associated cell monolayer. We find that simulations based on a purely mechanistic approach cannot capture the observed nonrandom cell configurations. Quantitative agreement with experimental data, however, is achieved when considering a minimal cognitive model of the flagellar mechanosensing.《滑行衣藻种群的运动与自组织》论文补充材料 纤毛（cilia）与鞭毛（flagella）这类细胞附属结构是通用功能模块，除承担多种关键生理功能外，还可帮助细胞及微生物在多样环境中自主移动。单细胞双鞭毛微生物莱茵衣藻（Chlamydomonas reinhardtii）在浮游（即自由游动）状态下，会通过周期性的蛙泳式鞭毛摆动排开周围流体。附着于表面的莱茵衣藻细胞则呈现另一种由鞭毛介导的运动模式：它们借助鞭毛内运输（intraflagellar transport）系统实现力传导，从而沿表面滑行。实验与运动统计分析表明，该滑行运动可促进细胞聚集，并支撑莱茵衣藻种群的自组织过程。本研究采用闵可夫斯基泛函（Minkowski functionals）对附着表面的单细胞层的时空组织特征进行表征。研究发现，仅基于纯机制方法构建的模拟无法复现实验中观测到的非随机细胞排布；但若引入针对鞭毛机械感知的极简认知模型，则可实现与实验数据的定量吻合。