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C. elegans lecture #2
Suppressor/enhancer genetics as a discovery system
epistasis analyses
Cell divisions in the development of the vulva
lin-4 mutants were found to be vulvaless
Suppressor screening on lin-4(e912)
Po
EMG mutagenize lin-4(e912) hermaphrodites (no vulva)
F1
lin-4(e912)/lin-4(e912); */+ (rare dominant suppressor)
F2
lin-4(e912)/lin-4(e912); */* (rare recessive suppressor)
What the screen identified: lin-14(lf) and lin-28(lf) cause precocious
expression of adult lineage! This is a much more subtle phenotype
than lin-4(lf) bag-o-worm phenotype, so not easy to identify in a
wild type background but they do emerge in a suppressor screen.
Pathway building: epistasis analyses
Temporal expression patterns of heterochronic pathway components
Mechanisms of actions of microRNAs
RNAi