INTRO
In 1963 Sydney Brenner age 36, introduced Caenorhabditis elegans (C. elegans) as a model organism for developmental biology and the study of the nervous system. A model organism is an animal model with certain characteristics that make it easy to use. Dr. Brenner found that C. elegans meets a certain set of criteria that make it a model organism. Such as having a rapid life cycle, a simple reproductive cycle, and small in size and easily observed phenotypic characteristics. Within three years this model organism was used to discover more than 300 mutations caused by mutagens [1].
39 years later Dr. Brenner won the Nobel Prize in physiology or medicine for his work with C. elegans. Since its introduction by Dr. Brenner this organism has …show more content…
The approach used by Dr. Brenner; examine the way of induced mutations in C. elegans. There are two C. elegans sexes: a self-fertilizing hermaphrodite (XX) and a male (XO) there is no separate female sex. When a male mates with a hermaphrodite there is up to a 50% chance that the offspring will be male. But when a hermaphrodite self-fertilizes there’s about a 0.1% chance that a male will arise. Hermaphroditic self-mating allows efficient generation of recessive mutants and a single hermaphrodite has about 300 progeny. Ethyl Methanesulfonate (EMS) is a chemical that adds an alkyl groups to nucleotides, it is considered a chemical mutagen. Using this mutagen on the P0 generation of C.elegans and examining F2 generations, the mutation VAB-1 is of interest for this lab. This mutation expresses a phenotype of a notched head (Figure-1). By examining the F2 generation for this particular phenotype, isolation and replication of that phenotype will be goal of this lab. The VAB_1 mutation is most similar (59% identical, 72% similarity) to that of human EphA3/Hek [4]. The EphA3 is associated with protein-tyrosine kinases that show to be silenced in leukemia. Also EphA3 numbers and expression levels were decreased in lung cancers …show more content…
First sterilize the work area to avoid contamination and by wearing gloved during the whole procedure. Then sterilize the platinum wire by flaming it, then allowing it to cool and proceed to pick up the worm and move to a new plate, then resterilize after moving the worms. Those worms will lay eggs in those plates, within 12-24 hours move those same worms that laid eggs in the first plate to new plated labeled P0B(1-5) to lay another set of eggs (using the same method as before). These will be 2 sets of F1 generations. After 12-24 hours pick the worms from P0B plates 1-5 and burn them. After 1-2 days has passed from when the POA and POB plates possessed eggs, worms of that F1 generation should be present. Then using the same moving procedures as before move 4-5 POA worms from each plate into a new plate labeled F1A(1-5). And repeat the same for POB(1-5) to F1B(1-5). After 24 hours those 4-5 worms in each of the F1 plates have laid eggs, and they can now be flamed or killed, leaving only eggs in all F1 generation plates. After the eggs hatch observations can begin, screening for desired phenotypes. As the desired phenotypes are located they can then be moved to the small NGM plates to further develop. After those chosen worm that represent the notch head phenotype lays eggs do not flame the worm and allow for F3 generation to