Formation of multicellular colonies by choanoflagellates increases susceptibility to capture by amoeboid predators
Formation of multicellular colonies by choanoflagellates increases susceptibility to capture by amoeboid predators
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DOI：
10.1111/jeu.12961
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发表时间：
2022-12
影响因子：
2.2
通讯作者：
Nicole E. Chin;Tiffany C. Wu;J. Michael O'Toole;Kevin Xu;Tommie Hata;Mimi A. R. Koehl
中科院分区：
文献类型：
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作者：
Nicole E. Chin;Tiffany C. Wu;J. Michael O'Toole;Kevin Xu;Tommie Hata;Mimi A. R. Koehl
许多异养微生物真核生物是尺寸选择性饲养者。一些微生物通过形成多细胞菌落来增加其体积。我们使用领鞭毛虫（Salpingoeca helianthica）（可以是单细胞或多细胞菌落）来研究多细胞性对猛禽原生动物捕食者变形虫（变形虫）捕食的脆弱性的影响，变形虫用伪足捕获猎物。用于测量向日葵和变形杆菌相互作用的行为的视频显微摄影术显示，大领鞭毛虫菌落比小菌落或单细胞更容易被捕获。游泳的菌落比游泳的单细胞领鞭毛虫产生更大的流场，并且当伪足形成开始时，向日葵与变形杆菌的距离对于菌落来说比单细胞更大。猎物的大小并不影响伪足形成的数量和伪足形成之间的时间、伪足的脉动运动学和延伸速度，或捕食者损失的猎物百分比。 S. helianthica 不会因伪足的追赶而改变游泳速度或执行逃跑动作，因此 A. proteus 的尺寸选择性取食是由于捕食者行为而不是猎物逃跑。我们的结果并不支持这样的理论：类领鞭毛动物祖先成为多细胞的选择优势降低了对原生动物捕食的敏感性。
Many heterotrophic microbial eukaryotes are size‐selective feeders. Some microorganisms increase their size by forming multicellular colonies. We used choanoflagellates, Salpingoeca helianthica, which can be unicellular or form multicellular colonies, to study the effects of multicellularity on vulnerability to predation by the raptorial protozoan predator, Amoeba proteus, which captures prey with pseudopodia. Videomicrography used to measure the behavior of interacting S. helianthica and A. proteus revealed that large choanoflagellate colonies were more susceptible to capture than were small colonies or single cells. Swimming colonies produced larger flow fields than did swimming unicellular choanoflagellates, and the distance of S. helianthica from A. proteus when pseudopod formation started was greater for colonies than for single cells. Prey size did not affect the number of pseudopodia formed and the time between their formation, pulsatile kinematics and speed of extension by pseudopodia, or percent of prey lost by the predator. S. helianthica did not change swimming speed or execute escape maneuvers in response to being pursued by pseudopodia, so size‐selective feeding by A. proteus was due to predator behavior rather than prey escape. Our results do not support the theory that the selective advantage of becoming multicellular by choanoflagellate‐like ancestors of animals was reduced susceptibility to protozoan predation.