7.3.1 - Producing recombinant DNA Flashcards
What is recombinant DNA?
DNA that has been formed artificially by combining DNA from different organisms.
How can artificial copies of a desired gene be made using reverse transcriptase?
Take an mRNA molecule transcribed from the gene and use it to produce the correct DNA sequence.
This process uses reverse transcriptase and reverses the transcription to produce complementary DNA which can act as an artificial gene.
How can a specific gene be produced from a DNA strand using restriction endonucleases?
They cut up DNA into small pieces.
Each type of endonuclease will cut DNA at specific sites.
Sticky ends will form.
What are two methods of producing a desired gene from DNA to make recombinant DNA eventually?
Using reverse transcriptase
Using restriction endonucleases
How do sticky ends form?
Some restriction endonucleases cut the DNA in a way such that there are a few more bases on one strand than the other.
What vector is often used to carry DNA into a host bacterial cell?
A Plasmid
What enzyme is used to help join the DNA and the plasmid back together?
DNA ligase
Is the plasmid cut with the same restriction endonuclease as the one that was used to cut the DNA strand?
YES
What can marker genes be used to do?
Can be used to identify transformed cells - cells that have taken up the vector
What is replica plating?
A process used to identify recombinant cells. It allows us to see colonies that survive in the presence of a certain antibiotic or without some nutrients for example.
In what situation may vectors other than plasmids be used to transfer DNA to a host cell?
Carrying DNA into human cells.
What are some vectors that can be used instead of plasmids for inserting DNA into human cells?
Gene guns
Liposome wrapping
Using viruses
MIcroinjection
How does a gene gun work?
DNA shot into the cell at a high speed carried on small gold or tungsten pellets.
How does liposome wrapping work?
Gene wrapped in liposomes (spheres formed from a lipid bilayer). These fuse with the cell membrane and can pass through to deliver DNA to the cytoplasm.
How can viruses be used as a vector?
A harmless virus can be engineered to carry a desirable gene and then infect animal cells.
