5

Question 1

Ways to regulate

Answer 1

Initiate transcription, posttranscriptional processing (pre > mature) (?), RNA stability (?), translation, protein modification, protein transport, protein degredation

Question 2

Negative vs positive control

Answer 2

repressor vs activator. repressor blocks place where polymerase would go

Question 3

Where else could repressor and activator bind to?

Answer 3

Enhancers, which can then loop to interact with the RNA polymerase

Question 4

What things might bind to an activator that’s bound to an enhancer?

Answer 4

Coactivator, corepressor (which would block interaction with polymerase)

Question 5

What is an insulator?

Answer 5

CRE that can get bound and form a loop that does not allow interaction between enhancer-binding proteins and the polymerase

Question 6

What is a CRE?

Answer 6

Short sequences (5-15) that help to regulate genes on the same piece of DNA

Question 7

When glucose and lactose is present, what happens to regulation of Lac?

Answer 7

Repressor unbound, activator unbound, very low transcription

Question 8

Glucose but no lactose?

Answer 8

Activator unbound, repressor bound, no transcription

Question 9

No glucose, yes lactose

Answer 9

activator bound, repressor unbound

Question 10

Is the repressor or activator related to lactose?

Answer 10

Repressor; activator related to the presence of glucose

Question 11

In prokaryotes, are there enhancers that make loops, or are the repressors binding in the promoter and the activators binding right next to the promoter?

Question 12

Main way that transcription is repressed in eukaryotes

Answer 12

Chromatin being wrapped up

Question 13

Can activators bind downstream of the gene in eukaryotes?

Answer 13

Yes

Question 14

Motif

Question 15

Helix-turn-helix

Answer 15

Motif that can interact with DNA
AHelix, Bturn, Ahelix

Question 16

Most TFs contain a…

Answer 16

Leucine zipper that looks like chopsticks

Question 17

How do TFs bind to the right site if the DNA has 2 strands bound to each other?

Question 18

small RNAs

Answer 18

miRNA (micro RNA) siRNA (small interfering?)

Question 19

miRNA, siRNA

Answer 19

small sequence with complementarity that binds to mRNA and targets for degredation (check) and prevents translation

Question 20

What is a silencer? Can a repressor bind to an enhancer?

Question 21

Proteasome part that opens up

Answer 21

19S regulartory particle

Question 22

Which section of the proteasome chews the protein

Answer 22

20S core

Question 23

What sends a protein to proteasome?

Answer 23

Polyubiquitination

Question 24

What does acetylation of a protein do?

Answer 24

Prevent ubiquitination of a protein

Question 25

Are there a bunch of proteins that transfer ubiquitin (>3) or are they individually pretty flexible?

Answer 25

Many

Question 26

Allostery

Answer 26

Binding of one thing affects the binding of something else

Question 27

H3 (histone protein) (and 16S)

Answer 27

used as control for western blot; constitutive

Question 28

Now stain is commonly

Answer 28

They stain all proteins as control

Question 29

lacO

Answer 29

can have a repressor or activator

Question 30

Is lacO directly upstream or downstream of a promoter?

Answer 30

Downstream

Question 31

Repressors bind to

Answer 31

operators

Question 32

Inducer

Answer 32

bind to repressor at allosteric domain and make the repressor not bind to the operator

Question 33

Corepressor

Answer 33

bind to repressor at allosteric domain and make the repressor bind to the operator

Question 34

Inhibitor

Answer 34

Prevents binding of activator to DNA

Question 35

Activator

Answer 35

can bind to promoter or operator (?)

Question 36

Effector

Answer 36

Allows binding of activator to DNA

Question 37

Why no operons in animals?

Question 38

What is allolactose used for?

Answer 38

To be an inducer

Question 39

Lac operon controls proteins that allow for...

Answer 39

the breakdown of lactose

Question 40

LacI

Answer 40

not part of lac operon

Question 41

When is lacI expressed?

Answer 41

Always; constitutively

Question 42

What does lacI code for?

Answer 42

A repressor

Question 43

When allolactose is bound to the repressor, what happens?

Answer 43

The repressor is not bound to the operator sequence

Question 44

Where does positive control occur in the lac operon?

Answer 44

at the lac promoter

Question 45

What binds to the promoter to promote expression?

Answer 45

CRP-cAMP; present when glucose is not present

Question 46

Z

Answer 46

first enzyme that breaks lactose down

Question 47

Y

Answer 47

permease (allows lactose inside)

Question 48

A

Answer 48

gets rid of harmful byproducts of lactose use

Question 49

Can lacI be trans-acting?

Answer 49

Yes

Question 50

Super-repressor

Answer 50

Cannot bind to allolactose

Question 51

In promoter, what does RNA polymerase recognize?

Answer 51

-10 and -35??

Question 52

Tryptophan operon

Answer 52

If there is tryptophan, they don't need more; tryptophan is a corepressor

Question 53

What proteins are made by the trp operon?

Answer 53

5 enzymes for making tryptophan

Question 54

Where does the repressor bind on the trp operon?

Answer 54

Operator

Question 55

What is the gene called that codes for the repressor related to the lac operon?

Answer 55

lacI

Question 56

Leader region (trpL)

Answer 56

has attenuator region

Question 57

Charged tRNA trp

Answer 57

tRNA without the trp

Question 58

Transcription terminates or proceeds depending on availability of trp

Answer 58

How????????

Question 59

3-4 halts

Question 60

Poly U tail being near the 3-4 destabilizes it???

Question 61

Wait what???? is

Question 62

Why does ribosome stall when you don't have trp on the trp codon

Answer 62

Oh i get it

Question 63

Ribosome stalls, then what

Answer 63

when the ribosome stalls, loops are formed that allows transcription to continue

Question 64

Arabinose operon

Answer 64

sugar that bacteria can use as a carbon source

Question 65

Arabinose absent, inducer site bound and O2 site bound, maybe because more regulator protein or maybe because there wasn't the CAP-cAMP?

Question 67

Trp, arabinose, lac