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Caenorhabditis elegans was initially described and named Rhabditis elegans by Maupas (1900) who collected it from rich humus soil in Algeria (north Africa) (Fatt, 1961); it was subsequently placed in the subgenus Caenorhabditis by Osche (1952) and then raised to generic status by Dougherty (1955).
The name is a blend of Greek and Latin (Caeno, recent; rhabditis, rod-like; elegans, elegant).
Sources: Fatt (1961), Nigon, (1949).
Much of the recognition for the selection and development of C. elegans as a model system in genetics and developmental biology can be attributed to Ellsworth C. Dougherty. In 1964, while working in the Department of Nutritional Sciences at UC Berkeley and interested in axenic culture of nematodes, Dougherty introduced the idea of using C. elegans to Sydney Brenner and provided him with a culture of the nematode.
Two strains of C. elegans have historical importance. One strain, Bergerac, was collected in 1955 from the garden soil near Bergerac, France, by Victor Nigon of the Universite de Lyon (Nigon 1949; Fatt, 1961), and the other strain, Bristol, was isolated by L.N. Staniland (National Agricultural Advisory Service, London) from mushroom compost near Bristol, England (Nicholas et al. 1959).
Study of development and reproduction of C. elegans was possible because the strains were morphologically identical but physiologically different (Fatt, 1961). The Bergerac strain of C. elegans could not be cultured at temperatures above 18C; at that temperature it became infertile. The Bristol strain can be cultured at temperatures up to 25C, though males will not copulate below 20C (Fatt and Dougherty, 1963; Nicholas, 1975). In several reported cases, rhabditid nematodes seem to be adversely affected by higher temperatures. For example, embryogenesis fails at temperatures of 25C and higher in Rhabditis cucumeris isolated from soil in the Central Valley of California (Venette and Ferris, 1997).
Figure from Ankeny, 2001
Sydney Brenner obtained his culture of the Bristol strain of C. elegans from Dougherty (Brenner, 1974). Virtually all C. elegans genetics has been done with the Bristol strain, more specifically with the N2 line that Sydney Brenner derived from the Bristol culture he obtained from Ellsworth Dougherty.
Interestingly, until the mid 1970s, people working in developmental biology frequently confused C. briggsae and C. elegans and many of the cultures being used were mis-identified. In the mid 1970s, graduate student Paul Friedman working with Ed Platzer at UC Riverside developed diagnostic biochemical criteria for separating the two species and resolved the confusion (Friedman et al, 1977).
Studies on C. elegans include areas of:
Human Disease Model
Nobel prizes in 2002 and 2006 were awarded for studies that used C. elegans as a model system.
Bacteria; laboratory cultures are usually maintained on Escherichia coli OP50 (a gram negative rod-shaped bacterium) maintained on defined media: NGM (= nematode growth medium):
Eggs may hatch within the bodies of older females. The females then die and the juveniles consume bacteria decomposing the female body. This has been thought to occur when the vaginal muscles are no longer strong enough to eject the eggs and is termed endotokia matricida due to the resultant death of the female. In the Caenorhabditis elegans literature, the phenomenon has been termed "bagging" . The hypothesis has been advanced that intra-uterine hatch is a part of the C. elegans life cycle, and complements androdioecy ( the existence of a hermaphrodite population and a male population) and the dauer (a resistant or enduring stage) stage to enhance progeny survival and dispersal under stress. Consequently, per the hypothesis, matricidal hatching, has been perpetuated in C. elegans through evolutionary time as it confers a survival advantage when resources are scarce or conditions unfavorable (Chen & Caswell-Chen, 2003).
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