Myxococcus xanthus creates complex and dynamic multicellular patterns as it swarms. The cells have two polar gliding engines: pulling type IV pili at their leading pole and pushing slime secretory nozzles at their lagging pole. Evidence is presented that slime secretion is vital for cell survival and that the peptidoglycan/cytoskeleton serves as a template to keep both engines oriented in the same direction. Swarming requires that each cell periodically reverse its gliding direction. For the leading pole to become the trailing pole, old engines are inactivated at both ends while new engines are being created at both ends. Reversal is initiated by a small G-protein reversal switch; a pulse of frzE approximately P from a reversal clock triggers MglA to bind GTP. Mgl.GTP then recognizes the engines that are currently in use and inactivates both of them. Meanwhile, new engines appear as instructed by the template, and the cell starts to glide in the opposite direction.

中文翻译：

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粘球菌-从单细胞极性到复杂的多细胞模式。

黄色粘球菌在成群时会产生复杂而动态的多细胞模式。牢房有两个极地滑行引擎：在其前极拉动IV型菌毛，在其滞后极推粘液分泌喷嘴。证据表明，粘液分泌对于细胞存活至关重要，而肽聚糖/细胞骨架可作为模板使两个引擎保持相同方向。编组要求每个单元格定期反转其滑动方向。为了使导杆成为尾随杆，在两端停用旧引擎，而在两端创建新引擎。逆转由小的G蛋白逆转开关启动；来自反转时钟的大约f的frzE脉冲触发MglA绑定GTP。Mgl。然后，GTP会识别当前正在使用的引擎并将它们都停用。同时，按照模板的指示出现新的引擎，并且该单元开始向相反的方向滑动。