Proten synthesis, prions, gene regulation, and epigenetics

Question 1

What are the two different ways an enhancer can act

Answer 1

Cis or trans (local or long distance)

Question 2

What was the point of the olfactory receptor enhancer lesson

Answer 2

Different olfactory receptors may have had different sequences but the same enhancer sequence for all

Question 3

What is a ortholog

Answer 3

Same gene found in two different species

Question 4

How many reading frames do you need to determine if there is a protein-encoding sequence present

Answer 4

6

Question 5

What is most cellular RNA made of

Answer 5

rRNA and tRNA

Question 6

How much GTP is used in peptide growth

Answer 6

4 PO4 bonds: 2 loading A.A. onto tRNA, 1 when freeing elongation factor, 1 during peptide translocation

Question 7

What two modifications are typically made if a gene is silenced

Answer 7

Heavy methylated or bound by histones

Question 8

Define epigenetic

Answer 8

A change in phenotype brought about by heritable changes in gene regulation rather than the genotype itself

Question 9

What does constitutive mean

Answer 9

always on

Question 10

Does H3K9 turn on or off when methylated

Answer 10

5’ end= activation Farther 3’= deactivation

Question 11

Definition of monocistronic

Answer 11

mRNA that caries the genetic information to translate a single protein chain (usually eukaryotes)

Question 12

What are some of the ways gene expression is regulated

Answer 12

1. Transcriptional level
2. Transript processing and stability
3. Way protein is folded
4. Export out of nucleus
5. Assembly of ribosomes at 5’ end
6. Transnational control

Question 13

How much of a cell’s RNA is mature (%)

Answer 13

3-5%

Question 14

Does H3K4 turn on or off when trimethylated

Answer 14

On

Question 15

What do insulators do

Answer 15

prevent enhancers from up regulating irrelevant promoters

Question 16

What is a gene

Answer 16

Complete chromosomal segment responsible for making a functional product

Question 17

Does AcH3 histone turn off or on when acetylated

Answer 17

On

Question 18

What is the most important level of gene regulation

Answer 18

Transcription

Question 19

T/F: the lowest free energy state of protein is always the best to be in

Answer 19

False

Question 20

What does a chaperone do

Answer 20

Sequesters polypeptide away from other proteins to prevent aggegation

Question 21

Is a vaccinia virus in DNA in the cytoplasm part of your genome

Answer 21

No

Question 22

How transmissible are TSE’s

Answer 22

Very, transmitted by blood or can grow inside of a plant that has been exposed to the disease

Question 23

What is a clinical significance of histone bookmarking

Answer 23

Environmental exposures that affect epigenetic marks may affect phenotype for future generations (Rat vinclozolin example)

Question 24

What are transmissible spongiform encephalopathies

Answer 24

inappropriate chaperone-like activity.

Question 25

What is histone bookmarking

Answer 25

Histone modifications may stay in the same place into next generation

Question 26

What is stochastic gene expression

Answer 26

Random intrinsic noise involving expression of different proteins that are not made at the same levels within individual cells

Question 27

Where does transcription start

Answer 27

transcription start site

Question 28

Why is there so little mature RNA in a cell

Answer 28

most fails to mature, and it's short lived

Question 29

What is the mode of action for AZT

Answer 29

Inhibits DNA synthesis by terminating biosynthesis of nascent DNA molecule

Question 30

What mechanism do humans use to amplify the number of proteins

Answer 30

Alternative splicing

Question 31

What is primary protein structure

Answer 31

Linear sequence of amino acids

Question 32

What is a homolos

Answer 32

Similar gene

Question 33

What is secondary protein structure

Answer 33

Simple folds/coils

Question 34

what does an enhancer do

Answer 34

organize transcription factors and RNA polymerase on the promoter

Question 35

What is cachexia

Answer 35

Wasting away: rapid cellular proliferation, increased metabolisim

Question 36

Definition of polycistronic

Answer 36

mRNA that can encode more than one polypeptide separately within the same RNA molecule. (usually bacteria)

Question 37

Where does elongation factor load onto

Answer 37

'A' site of ribosome

Question 38

How can we take advantage of self-assembling nature of PrPsc

Answer 38

Amplify samples to detectable levels

Question 39

What does the promoter do

Answer 39

Assembly of RNA polymeraze complex with transcription. 5' end

Question 40

What are some transcriptional control elements (5)

Answer 40

1. Promoters 2. Enhancers 3. Silencers 4. DNA-binding proteins 5. Insulators

Question 41

What is a paralog

Answer 41

Multiple genes within a specie derived from ortholog

Question 42

Where does transcription stop

Answer 42

terminator

Question 43

What turns a promoter on

Answer 43

Enhancer

Question 44

Do epigenetic effects often have memory

Answer 44

Yes

Question 45

What is tertiary protein structure

Answer 45

overall conformation made up of multiple primary and secondary structures

Question 46

Why is stochastic gene expression significant

Answer 46

tumor suppressor genes if they are too variable my not produce enough at the right time losing regulation ability

Question 47

T/F: Some modifications of proteins are more resistant to TSE than the wild types

Answer 47

True

Question 48

What is quaternary protein structure

Answer 48

Multi-subunit associations of sub-units to make complete protein