Microfluidic platform with spatiotemporally controlled micro-environment for studying long-term C. elegans developmental arrests

Abstract

Animals’ long-term survival is dependent on their ability to sense, filter and respond to their environment at multiple timescales. For example, during development, animals integrate environmental information, which can then modulate adult behavior and developmental trajectory. The neural and molecular mechanisms that underlie these changes are poorly understood. C. elegans is a powerful model organism to study such mechanisms; however, conventional plate-based culturing techniques are limited in their ability to consistently control and modulate an animal’s environmental conditions. To address this need, we developed a microfluidics-based experimental platform capable of long-term culture of a population of developing C. elegans covering the L1 larval stage to adulthood, while achieving spatial consistency and temporal control of their environment. To prevent bacterial accumulation and maintain optimal flow characteristics and nutrient consistency over the operational period of over one hundred and fifty hours, several features of the microfluidic system and the peripheral equipment were optimized. By manipulating food and pheromone exposure over several days, we were able to demonstrate environmental-dependent changes to growth rate and entry to dauer, an alternative developmental state. We envision this system to be useful in studying the mechanisms underlying long timescale changes to behavior and development in response to environmental changes.

Changes to social feeding behaviors are not sufficient for fitness gains of the Caenorhabditis elegans N2 reference strain

“…For crude pheromone assays, crude pheromone was prepared as described previously ( Zhuo et al, 2017 ). The crude pheromone was resuspended in ethanol and stored in −20°C.…”

The Egg-Counter: A novel microfluidic platform for characterization ofCaenorhabditis elegansegg-laying

“…The second, the resistance chip (Figure 2a, Supplemental figure 6 and online collection 52 ), is used in series with the Egg-Counter chip to increase the total resistance for the system. The increase in total resistance better aligns the operating pressure with the operating range of the pressure regulator, enabling finer control of perfusion speed, while minimizing negative effects due to variability in pressure regulation over the duration of an experiment as previously published 72 . Both devices were designed using Vectorworks 2013 Fundamentals (Nemetschek SE, Munich, DE).…”

The egg-counter: a novel microfluidic platform for characterization of Caenorhabditis elegans egg-laying

“…The increase in total resistance better aligns the operating pressure with the operating range of the pressure regulator, enabling finer control of perfusion speed, while minimizing negative effects due to variability in pressure regulation over the duration of an experiment as previously published. 72 Both devices were designed using Vectorworks 2013 Fundamentals (Nemetschek SE, Munich, DE). Photomask transparencies were printed at 25400 dpi (“20 k resolution”, CAD/Art Services Inc, Bandon OR, United States).…”