20 - TRANSPOSABLE ELEMENTS Flashcards
how are different grape colors caused by transposable elements
peppered moth and transposable elements (TS PMO)
what are the points to keep in mind about genome surveillance
how was the P element in drosophila discovered
a type 1 transposon
discovered when lab and wild caught strains of flies were crossed
what happened when they switched the sex of the fly which was lab grown and wild caught and what interpretation can we derive from that
what is the mechanism of what was happening inside the flies to yield those results
characteristics of the Tc1 element
what is the observation regarding Tc1 that was made and what hypothesis was derived from that
how do we identify the genes that cells use to repress TE mobility?
how does Tc1 insertion disrupt the unc-22 gene function
what experiment was done and what could they infer from that
induce random mutations
most worms will still be uncoordinated
rare worms will be smooth gliding worms (the progeny will be, since this happens in the germline)
means that the knocked out genes were involved in Tc1 silencing, since their removal allowed Tc1 to jump out and restore the unc22 function
what was done to the worms that were smooth gliding
bred (hermaphrodites so crossed to each other) individually to generate a new strain that contains the mutation that was introduced
what happened to those worms that were smooth gliding?
unc22 gene was reverted to WT
the Tc1 element was mobilised
a gene was mutated, which allowed Tc-1 to jump out and restore unc22
how could you tell if the same gene was knocked out in each worm that was smooth gliding?
by doing a complementation test
how many genes are involved in blocking Tc1 mobility?
by screens, 25 genes were identified which block Tc1 mobility
many of these genes are involved in the RNAi silencing pathway
what is the RNAi silencing pathway
how can a single Tc1 repress mobility of all Tc1 in a cell
