Transposons Flashcards
When were transposons first discovered?
In 1940, when genetic elements from maize moved from site to site
What % of human genes are transposons?
50%
Why do transposons need transposase?
Bind at specific recombinase providing the ability for it to hop between locus’
What target bias to transposons show?
They tend to avoid highly expressed genes
How frequent does transposition occur?
every 100- 1 million cell divisions
Asides from tranposase genes what else must a transpon carry
Inverted repeat flanks
What is the cut and paste mechanism of jumping?
DNA splicing will cut out the target sequence, where the transposon will then insert itself
What are the IS elements of a transposon?
A tranposase with inverted flanking repeats
What are composite transposons
Contain a central non-tranpositional core, with an IS element on either side
Why can’t TN3 and TN7 land near eachother?
Due to them being the same type, Prevents them from inactivating the original
What can transposons be used for?
Can be used to produce the randomly marked areas of mutation
Why is TN5 used within the lab to map mutageneis of transposons?
- High jump frequency
- Little specificity
What are integrons?
Gene acquisition hotspots which allow for rapid evolution
What is phage MU?
A bacteriophage of E.coli
