elegans can also endure harsh environmental conditions by switching to a facultative diapause stage called the dauer larva which can survive four to eight times the normal 3-week life span ( Cassada and Russell, 1975).ĭespite its simple anatomy, the animal displays a large repertoire of behavior including locomotion foraging feeding defecation egg laying dauer larva formation sensory responses to touch, smell, taste, and temperature and some complex behaviors like male mating, social behavior, and learning and memory ( Rankin, 2002 de Bono, 2003). The strains can be kept as frozen stocks for long periods of time. Mutant animals are readily obtained by chemical mutagenesis or exposure to ionizing radiation ( Anderson, 1995 Jorgensen and Mango, 2002). Dotted lines and numbers mark the level of each section shown in IntroFIG 2. Schematic drawing of anatomical structures, left lateral side. DIC image of an adult hermaphrodite, left lateral side. IntroFIG 1: Anatomy of an adult hermaphrodite. Self-fertilization of the hermaphrodite allows for homozygous worms to generate genetically identical progeny, and male mating facilitates the isolation and maintenance of mutant strains as well as moving mutations between strains. Males arise infrequently (0.1%) by spontaneous non-disjunction in the hermaphrodite germ line and at higher frequency (up to 50%) through mating. elegans sexes: a self-fertilizing hermaphrodite (XX) and a male (XO). The anatomical description of the whole animal has been completed at the electron microscopy level and its complete cell lineage, which is invariant between animals, has been established ( Brenner, 1973 Byerly et al., 1976 Sulston et al., 1983 Wood, 1988a Lewis and Fleming, 1995). It can be examined at the cellular level in living preparations by differential interference contrast (DIC) microscopy, because it is transparent throughout its life cycle. The animal can be maintained in the laboratory where it is grown on agar plates or liquid cultures with E. It reproduces with a life cycle of about 3 days under optimal conditions. elegans is amenable to genetic crosses and produces a large number of progeny per adult.
The adult body plan is anatomically simple with about 1000 somatic cells. Among its many advantages for study are its short life cycle, compact genome, stereotypical development, ease of propagation and small size. It is an important model system for biological research in many fields including genomics, cell biology, neuroscience and aging ( ). Hermaphrodite Introduction Handbook - IntroductionĬlick pictures for new window with figure and legend, click again for high resolution imageġ Caenorhabditis elegans as a Genetic OrganismĬaenorhabditis elegans is a small, free-living soil nematode (roundworm) that lives in many parts of the world and survives by feeding on microbes, primarily bacteria ( IntroFIG 1).
0 kommentar(er)
