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Phenotyping single-cell motility in microfluidic confinement.

ABSTRACT: The movement trajectories of organisms serve as dynamic read-outs of their behaviour and physiology. For microorganisms this can be difficult to resolve due to their small size and fast movement. Here, we devise a novel droplet microfluidics assay to encapsulate single micron-sized algae inside closed arenas, enabling ultralong high-speed tracking of the same cell. Comparing two model species - Chlamydomonas reinhardtii (freshwater, 2 cilia), and Pyramimonas octopus (marine, 8 cilia), we detail their highly-stereotyped yet contrasting swimming behaviours and environmental interactions. By measuring the rates and probabilities with which cells transition between a trio of motility states (smooth-forward swimming, quiescence, tumbling or excitable backward swimming), we reconstruct the control network that underlies this gait switching dynamics. A simplified model of cell-roaming in circular confinement reproduces the observed long-term behaviours and spatial fluxes, including novel boundary circulation behaviour. Finally, we establish an assay in which pairs of droplets are fused on demand, one containing a trapped cell with another containing a chemical that perturbs cellular excitability, to reveal how aneural microorganisms adapt their locomotor patterns in real-time.

SUBMITTER: Bentley SA

PROVIDER: S-EPMC9683786 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature

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Phenotyping single-cell motility in microfluidic confinement.

Bentley Samuel A SA Laeverenz-Schlogelhofer Hannah H Anagnostidis Vasileios V Cammann Jan J Mazza Marco G MG Gielen Fabrice F Wan Kirsty Y KY

eLife 20221123

The movement trajectories of organisms serve as dynamic read-outs of their behaviour and physiology. For microorganisms this can be difficult to resolve due to their small size and fast movement. Here, we devise a novel droplet microfluidics assay to encapsulate single micron-sized algae inside closed arenas, enabling ultralong high-speed tracking of the same cell. Comparing two model species - <i>Chlamydomonas reinhardtii</i> (freshwater, 2 cilia), and <i>Pyramimonas octopus</i> (marine, 8 cili ...[more]

PMID: 36416411

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Dataset Information

Phenotyping single-cell motility in microfluidic confinement.

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Phenotyping single-cell motility in microfluidic confinement.

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