Notes- February 3

V.) mRNA and cDNA
a.) Complenmentary DNA: It is complementary to an mRNA. (One use of cDNA-mRNA hybrid is to identify introngs in a gene.)
b.) Gene Chip Microarrays: To look at gen expression. (ex: to see if a gene is activated by a cell with that specific bacteria) If you shine the light on the slide, only the dots of cDNA that have fluorescent mRNA hybridized to them will light up. The lit up dots are the genes that are activated.
c.) Quantifying introns
d.) rtPCR (polymerase chain reaction) A technique to make copies of DNA from a small initial sample. (amplifys the DNA so you have enough of it) In a normal PCR the DNA strands are heated and then separated and then they are treated with the DNA polymerase, and that cools them down and you end up with double the amouont of DNA each time.
rtPCR (reverse transcriptase PCR): This is used to look at the changes in gene expression when looking at what genes transcribe. Begin with a sample of mRNA's from the cell. Then you treat the mRNA mix from the cell with reverse transcriptase(enzyme that copies RNA to DNA). After this you treat DNA copies of mRNA with primers from a gene of interest (ex: NFKB). Primers are specific to genes of interest, therefore that genes DNA will be copied by PCR.
-rtPCR tells us if a particular gene is expressed by showing whether gene's mRNA was copied or not copied by rtPCR steps.

To see if gene is activated (change DNA to RNA to protein) by the infection of a cell
1-treat slide with mRNA extracted from exp. and control cell
2-wouldn't expect to see hybridization on control, but should on the exp.
3-mRNA from cells have been tagged w/ flourescent molecule
4-shining right wavelength of light of slide, only dots of cDNA that hybridized with mRNA will show up- lit up genes=genes that are activated

Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-ShareAlike 3.0 License