EXAM: What I still don't know Flashcards
What enzyme relieves supercoiling?
DNA topoisomerases
What creates 5’ cap?
Capping proteins
What proteins bind to make poly A tail and cleave?
Cleavage and polyadenylation factors (CPSF, CstF)
Error rate of tRNA synthetase?
1/40,000
First thing initiator tRNA/small subunit complex does after binding?
Finds AUG site
What stops translation at the very end?
Release factors that bind and dissociate everything
What repressor adds with -lactose in LAC operon?
Lac repressor
What activator adds with -glucose in LAC operon?
CAP with cyclic AMP to activate
What transcription factor binds to TATA box in transcription initiation?
TBP with TFIID
What causes patterns of histone modification as the result of activator proteins?
histone modifying enzyme
What protein might cause mRNA to decay before translation and how?
deadenylase, binds to 5’ cap and eats tail
What protein might cause mRNA to decay before translation and how?
deadenylase, binds to 5’ cap and eats tail
What protein and system is involved in gene silencing via heterochromatin formation?
siRNAs binding to RITS, cause methylation and stops genes from going
What protein and system is involved in gene silencing via heterochromatin formation?
siRNAs binding to RITS, cause methylation and stops genes from going
I’m in the lab and I want to only grab C. el neuronal cells. What do I do?
Use FACS (Fluorescence-activated cell sorter). For separating cells from other tissues.
How would FACS work to grab C. elegans neurons?
- Bind antibody with a fluorescent dye to surface of neurons. Dye makes them neg charged
- They go down a tube. A laser shoots it
- Further down the tube, there are two electrical fields at opposing charges
- These separate now-negative neurons from positive other cells
Now I want to take those neurons and extract their nuclei. How do I start that?
Put test tube in a centrifuge, make it go
Now I want to take those neurons and extract NMDAR. How do I start that?
Put test tube in a centrifuge, make it go fast
I have C elegans and got a test tube with only proteins in it from centrifugation. I have a bunch of NMDAR already. How do I separate them?
Column chromatography
What do I tag the C. elegans proteins with to separate them with column chromatography?
Peptide epitope tags
What two chemicals do I have in front of my SDS page? Why?
SDS - to make my NMDARs negatively charged so they go down gel
B-mercaptoethanol - to break disulfide bonds in NMDARs
In my SDS page, how could proteins be negatively charged with SDS and still move along a charge gradient?
Makes some proteins more negatively charged than others?
What would I stain agarose gel with to see the NMDAR gene? What kinds of gels could I use?
Agarose gel to lots (1000) of nucleotide pairs
Polyacrylamide gel to see 50 nucleotides of the gene
Pulsed field gel to see entire chromosomes
How would I make the NMDAR gene radioactive to see where it is?
In situ hybridization: add 32p-labeled nucleotides, make polymerase duplicate using them
