Data from: Dynamics of cilia length in left-right development

Reduction in the length of motile cilia in the zebrafish left-right organizer (LRO), also known as Kupffer’s vesicle (KV), has a large impact on left-right development. Here we demonstrate through genetic overexpression in zebrafish embryos and mathematical modelling that the impact of increased motile cilia length in embryonic LRO fluid flow is milder than that of short cilia. Through Arl13b overexpression, which increases cilia length without impacting cilia beat frequency, we show that the increase in cilium length is associated with a decrease in beat amplitude, resulting in similar flow strengths for Arl13b overexpression and wild-type embryos, which were not predicted by current theory. Longer cilia exhibit pronounced helical beat patterns and consequently lower beat amplitudes relative to wildtype, a result of an elastohydrodynamic shape transition. For long helical cilia, fluid dynamic modelling predicts a mild (approximately 12%) reduction in the torque exerted on the fluid relative to the wildtype, resulting in a proportional reduction in flow generation. This mild reduction is corroborated by experiments, providing a mechanism for the mild impact on organ situs.