Upgrade to remove ads
Cycle 1: Trapping Light for Energy and Info
Channelrhodposin and Gene Expression
Terms in this set (20)
How does Chlamy know the direction of light?
light absorption blocked from the inner carotenoid layer; light absorbed from the outer carotenoid layer either directly or reflected
Which wavelength(s) of light does retinal absorb? Chlorophyll?
red and blue
Why can mouse opsin not be used? What are the additional components required for the optogenetics experiment?
Mouse opsin not an ion channel
1. promoter to drive expression of transfected opsin gene.
2. biosynthetic pathway to produce retinal
Photoisomerization vs. phototransduction vs. photosynthesis?
all involve electrons absorbing energy
photoisomerization and phototransduction involved in light detection and vision and require bond breaking
photosynthesis involves production of glucose and requires oxidation of chlorophyll
retinal cis to trans drives conformational change in opsin to open channelrhodopsin
retinal cis to trans triggers G-protein to activate a signal transduction pathway and cause an ion inflow
red-photon-energy e- used in ETC
Purpose of RNA blot analysis (Northern blotting)?
determine whether or not a gene is transcribed by detecting mRNA
Describe the DNA probes.
single stranded, 400 nucleotides, labelled with fluorescent marker
Product of translation?
unfolded, nonfunctional polypeptide which folds spontaneously and may have to bind cofactor
made up of fewer amino acids than its transcript predicts because signal peptide cleaved
How to measure gene expression?
transcript abundance that integrates rate of transcription and RNA degradation
protein abundance that integrates rate of rate of translation and protein breakdown
Stability of RNA?
much less stable than DNA; mRNA most unstable relative to rRNA and tTRNA
How is rate of transcription regulated?
protein factors on promoter regulating RNA polymerase
How is rate of translation regulated?
protein factors on mRNA regulating its stability
Average half-life and abundance of mRNA?
9h, 17 copies
Average half-life and abundance of protein?
46h, 16,000 copies
Purpose of Western blotting?
measure protein abundance
What does change in transcript abundance mean?
increase means transcription and decrease means degradation
When does max transcript abundance occur relative to max protein abundance?
induced increase thus slightly before
How does protein abundance typically change in different environments?
repressed or constitutive
This set is often in folders with...
Cycle 0: Chlamydomonas
Cycle 2: Molecular Evolution
Cycle 3: Thermodynamics and Membrane Biology
Cycle 4: Primary Metabolism
Other sets by this creator
Cycle 11: Epigenetics
Cycle 10: DNA Technologies
Cycle 9: Genetics of Cancer and Other Diseases
Cycle 8: Control of Gene Expression
Other Quizlet sets
AP Chem Test 4/21/21
Transducers & Temporal Resolution
Med Surge 3: Week 4