DNA Analysis Flashcards
Restriction endonucleases are isolated from what?
Bacteria
What are restriction endonucleases used to do?
Cut DNA at specific sites GAAGCC
How is DNA analyzed?
Used an agarose gel because the DNA is already charged due to its phosphodiester bonds. Load DNA onto gell and apply voltage
SDS-PAGE is not used because DNA is already charged
How can genes be cloned?
Genes can be cloned using bacteria. It is placed in circular, double stranded plasmid form so that the bacteria can be tricked to replicate it.
Cleavage with restriction nuclease and the DNA fragment to be cloned is covalently linked by DNA ligase
When are ligase reactions much easier?
Much easier with compatible cohesive ends
What have plasmids been engineered to serve?
Various functions i.e. carry and replicate manipulated gene products
Where can every gene in the human body be put into?
Into bacteria and stored indefinitely and propagated anytime
How are most genes discovered?
By using bacteria plasmids.
What is cDNA?
DNA copy of the messenger RNA. cant put an entire gene into bacteria easily. So we wait for the cell to create the final mRNA to use the condensed gene
Describe cDNA clones?
DNA copy of mRNA No introns Much smaller than original gene Requires viral enzyme -Reverse transcriptase
Using genes vs gene products, how are gene products more useful?
cDNA because it is smaller and there is no issue with randomly copping up the gene and getting gene fragments
How can fluorescence in situ hybridization be used?
Used to analyze the presence and locations of genes-cytogenetics
What are the starting points for transcription?
Primers (small ~20 nucleotides)
How can DNA transcription be used to amplify DNA synthesis?
Polymerase chain reaction PCR
What can PCR be used to detect?
Altered genes or foreign DNA
