lecture 13 - drosophila Flashcards
what are the advantages of using drosophila as a model organism?
it has a short generation time
it is easy to create transgenic line
we can create different phenotypes by crossing strains and genetic breeding
it only has 4 chromosomes: 1 XY and 3 autosomes
it has polytene nuclei which are very easy to analyze bcs of how observable their chromatin actually is
GAL4/UAS SYSTEM
in order to generate tissue specific expression
GAL4 is a gene that makes Gal4 which is a tf; it binds to UAS promoter sequence so it starts transcription of target gene provided that it has a UAS gene
promoter of GAL4 can be selected so that it is only activated in specific tissues. Usually, a heat shock promoter is used, resulting in many different fly lines with specific mutations
usually the father has the driver GAL4 sequence and the mother - the UAS target sequence with markers
what are polytene nuclei?
they are useful for seeing how DNA packages into chromosomes; DNA wrapped up on histones
They are much larger because DNA is replicated but no segregation occurs (or cell division)
they are all connected at the chromocenter
