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The course is based on the analysis of par mutants, par-2 and par-3, which have neat easily observable phenotypes - loss of asymmetry. The first session starts with the basics of C. elegans handling, plates, worm pick, etc..., then dissection and observation of wild-type early embryos. The first dissection is the most challenging part of the whole course and in one hour they are all able to get one embryo to look at. Usually they're able to see from pronuclear migration up to 4-cell stage. 2/n

For practical reasons on session 1 they setup a couple of experiments for the 3rd session: transferring par-2 mutant worms to par-3(RNAi) plates, for epistasis experiment, and worms carrying tissue-specific GFP reporters on par-2(RNAi) or par-3(RNAi) plates, to observe the phenotypes later in development.
The second session is the observation of par-2 and par-3 mutant embryos, same technique as for WT on session 1. They have a par-2 temperature-sensitive mutant, and a par-3 non-conditional 3/n

mutant, hence a strain with a balancer, so they play with different genetic tools. At the end of the session we discuss what the function of par-2 and par-3 may be, and formulate hypotheses. In particularly how par-2 and par-3 interact with one another, who's upstream or downstream, leading to the epistasis experiment: observe par-2(ts) par-3(RNAi) embryos, which is done on the third session.
The other, and final experiment, is to look at par-2(RNAi) or par-3(RNAi) terminally differentiated 4/n

embryos carrying tissue-specific GFP reporters (pharynx, body-wall muscle, germline, neurons, intestine or hypodermis). Each student does one GFP/RNAi pair condition, the results are made available to the whole class. This requires one epi-fluorecence microscope for the whole class on session 3.
In the end they can see early embryo development, genes involved in that process and whether those early events relate to later development.
It's easy to set up and most students enjoy it 5/5.