Self-sustained three-dimensional beating of a model eukaryotic flagellum
Self-sustained three-dimensional beating of a model eukaryotic flagellum
复制标题
模型真核鞭毛的自我维持三维跳动
DOI：
10.1039/d2sm00514j
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发表时间：
2022
期刊：
影响因子：
3.4
通讯作者：
Potomkin, Mykhailo
中科院分区：
文献类型：
--
作者：
Rallabandi, Bhargav;Wang, Qixuan;Potomkin, Mykhailo
鞭毛和纤毛是许多生物细胞的共同特征，在微尺度上对运动和摄食起着重要作用。鞭毛的跳动是由分子马达控制的，分子马达沿着鞭毛的长度沿着施加力，并由与鞭毛变形耦合的反馈机制调节。我们开发了一个三维（3D）鞭毛殴打模型的基础上滑动控制电机反馈，占弯曲和扭曲，以及微分弯曲阻力沿着和正交的主要弯曲平面的鞭毛。我们表明，跳动产生和持续自发足够高的电机活动，通过不稳定的机制。鞭毛的各向同性弯曲刚度导致三维螺旋跳动模式。相比之下，各向异性鞭毛呈现出丰富多样的波浪状跳动动力学，包括3D跳动模式以及平面跳动模式。我们表明，尽管3D的跳动机械产生近平面跳动的能力只需要适度的弯曲各向异性，是在许多真核生物鞭毛，如哺乳动物精子中观察到的一个功能。
Flagella and cilia are common features of a wide variety of biological cells and play important roles in locomotion and feeding at the microscale. The beating of flagella is controlled by molecular motors that exert forces along the length of the flagellum and are regulated by a feedback mechanism coupled to the flagella deformation. We develop a three-dimensional (3D) flagellum beating model based on sliding-controlled motor feedback, accounting for both bending and twist, as well as differential bending resistances along and orthogonal to the major bending plane of the flagellum. We show that beating is generated and sustained spontaneously for a sufficiently high motor activity through an instability mechanism. Isotropic bending rigidities in the flagellum lead to 3D helical beating patterns. By contrast, anisotropic flagella present a rich variety of wave-like beating dynamics, including both 3D beating patterns as well as planar beating patterns. We show that the ability to generate nearly planar beating despite the 3D beating machinery requires only a modest degree of bending anisotropy, and is a feature observed in many eukaryotic flagella such as mammalian spermatozoa.