Fluorescent beads are a Versatile tool for staging Caenorhabditis elegans in different life histories

Liberta Nika, Taylor Gibson, Rebecca Konkus, Xantha Karp

Research output: Contribution to journalArticlepeer-review

24 Scopus citations

Abstract

Precise staging of Caenorhabditis elegans is essential for developmental studies in different environmental conditions. In favorable conditions, larvae develop continuously through four larval stages separated by molting periods. Distinguishing molting from intermolt larvae has been achieved using transgenes with molting reporters, therefore requiring strain constructions, or careful observation of individuals for pharyngeal pumping or behavioral quiescence. In unfavorable conditions, larvae can enter the stressresistant and developmentally arrested dauer larva stage. Identifying dauer larvae has been based on their ability to withstand detergent selection, precluding identification of recovering animals or of mutants with defects in dauer morphogenesis. Here, we describe a simple method to distinguish molting larvae or dauer larvae from intermolt larvae that bypasses the limitations of current methods. Fluorescent latex beads are mixed with the bacterial food source and ingested by intermolt larvae and adults. Molting and dauer larvae do not feed, and therefore lack beads in their digestive tract. The presence of beads can be determined using a dissecting microscope at magnifications as low as 100 ×, or by using a wormsorter for high-throughput experiments. We find that continuously developing bead-lacking larvae display hallmarks of molting, including expression of the mlt-10::gfp molting marker and a lack of pharyngeal pumping. Furthermore, wild-type and mutant dauer larvae produced by any of three common methods are accurately identified by a lack of beads. Importantly, this method is effective in SDS-sensitive mutant backgrounds and can identify recovering dauer larvae, a stage for which there is no other method of positive selection.

Original languageEnglish
Pages (from-to)1923-1933
Number of pages11
JournalG3: Genes, Genomes, Genetics
Volume6
Issue number7
DOIs
StatePublished - Jul 1 2016

Keywords

  • C. elegans
  • Dauer
  • Fluorescent beads
  • Molting developmental stage

Fingerprint

Dive into the research topics of 'Fluorescent beads are a Versatile tool for staging Caenorhabditis elegans in different life histories'. Together they form a unique fingerprint.

Cite this