1 Crop Sciences Department, University of Illinois Urbana-Champaign
2 Neuroscience Department, Oberlin College, Ohio
3 Neuroscience Program, University of Illinois Urbana-Champaign
2 Neuroscience Department, Oberlin College, Ohio
3 Neuroscience Program, University of Illinois Urbana-Champaign
Correspondence to: Caroline Beshers (caroline.beshers13@gmail.com)
The dauer life stage in wild-type C. elegans exhibits morphological and behavioral characteristics that differentiate it from non-dauers (Hu, 2007). In addition to the commonly observed radial shrinkage, quiescence and lack of pharyngeal pumping, we noted a tendency of wild-type dauers to lie dorsoventrally when mounted on agarose slides, as opposed to laterally like adults. To quantify this observation, we mounted wild-type dauers and L3s on increasing concentrations of agarose with 0.1 M levamisole. We found that 75-90% of wild-type dauers mounted with levamisole lie dorsoventrally regardless of agarose concentration (Fig. 1). Very few (2.5-5%) non-dauer animals were positioned dorsoventrally. There was no significant difference in positioning between dauers that still retained their L2d cuticle and those that were unsheathed. We then utilized a non-anesthetic method of immobilization by mounting dauers on 10% agarose with 10 micron polystyrene microbeads (Kim et al., 2013). Interestingly, only 15% of wild type dauers lie dorsoventrally when mounted using the microbeads. We hypothesized that the radial shrinkage and the presence of lateral alae in wild-type dauer cuticles may cause anesthetized dauers to roll to a dorsoventral position, but that “conscious” dauers immobilized with microbeads would remain lateral, despite the presence of alae. To test this, we examined dex-1 mutant dauers. We recently found that dex-1(ns42) dauers are defective for dauer alae formation and radial constriction leading to a dumpy dauer phenotype. We found that dex-1 dauers are significantly more likely to lay laterally than wild-type dauers (p=0.0013) (Fig. 1) suggesting that dauer alae or overall body dimensions regulate the anesthetized “sleeping” position.
References
Hu, P.J. Dauer (August 08, 2007), WormBook, ed. The C. elegans Research Community, WormBook
Kim E, Sun L, Gabel CV, Fang-Yen C (2013) Long-Term Imaging of Caenorhabditis elegans Using Nanoparticle-Mediated Immobilization. PLoS ONE 8(1): e53419.
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Articles submitted to the Worm Breeder's Gazette should not be cited in bibliographies. Material contained here should be treated as personal communication and cited as such only with the consent of the author.
Articles submitted to the Worm Breeder's Gazette should not be cited in bibliographies. Material contained here should be treated as personal communication and cited as such only with the consent of the author.
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