WormFarm: a quantitative control and measurement device toward automated Caenorhabditis elegans aging analysis

Abstract

SummaryCaenorhabditis elegans is a leading model organism for studying the basic mechanisms of aging. Progress has been limited, however, by the lack of an automated system for quantitative analysis of longevity and mean lifespan. To address this barrier, we developed 'WormFarm', an integrated microfluidic device for culturing nematodes. Cohorts of 30-50 animals are maintained throughout their lifespan in each of eight separate chambers on a single WormFarm polydimethylsiloxane chip. Design features allow for automated removal of progeny and efficient control of environmental conditions. In addition, we have developed computational algorithms for automated analysis of video footage to quantitate survival and other phenotypes, such as body size and motility. As proof-of-principle, we show here that WormFarm successfully recapitulates survival data obtained from a standard plate-based assay for both RNAi-mediated and dietary-induced changes in lifespan. Further, using a fluorescent reporter in conjunction with WormFarm, we report an age-associated decrease in fluorescent intensity of GFP in transgenic worms expressing GFP tagged with a mitochondrial import signal under the control of the myo-3 promoter. This marker may therefore serve as a useful biomarker of biological age and aging rate.

Logarithmic bacterial gradient chip for analyzing the effects of dietary restriction on C. elegans growth

“…The nematode Caenorhabditis elegans (C. elegans) has been a primary model organism for studying basic mechanisms of aging and longevity physiology, because of its fully sequenced genome, short generation time (∼3.5 days at 20 • C) and lifespan (2-3 weeks) [6,7]. Several aging-related factors firstly uncovered from studies in C. elegans, such as the insulin/IGF-1 signaling pathway and the target of rapamycin kinase, are now well-known to similarly modulate longevity and aging in mammals [8].…”

“…Currently, researchers mainly use genetic and environmental manipulations to model DR condition to study the effect of food consumption on lifespan in C. elegans [7,9,10]. In the traditional methods, mutant worms (such as eat-2) with decreased feeding rate is used for genetically mimicking the worms treated with DR [11,12].…”

Highly efficient microfluidic sorting device for synchronizing developmental stages of C. elegans based on deflecting electrotaxis

“…1b). After transferring the chip into the electrophoresis chamber filled with electrophoresis buffer, an electric field was 15 applied to drive C. elegans to crawl into sorting channels (Fig. 1c).…”

“…8, ~76.41% of males and ~4.91% of hermaphrodites distributed into channels 4-6, as a result, these three channels were composed of ~93.96% of males. Channels 8-10 were composed of ~94.78% of hermaphrodites 15 and distributed with ~87.40% of hermaphrodites and ~4.81% of males. These results showed the feasibility of our method to sort C. elegans males.…”

“…29 Based on the enhanced locomotion behaviour when crawling in a micro-post array with the gap matching the wavelength of C. elegans, Han et al designed multi-arrayed channels featuring hexagonal microstructures in which C. elegans exhibited size-dependent movement. 30 Assisted 15 with the electric field driving C. elegans to crawl continuously, specific stage of C. elegans was successfully sorted with high purity. 31 Until now, no reported method was found to simultaneously sort or synchronize all the different stages of the worms.…”