Gene Expression and Regulation

Question 1

Transcriptional control, RNA processing, RNA transport, translational control, mRNA degradation, and protein processing all control ____ ____.

Answer 1

Gene expression

Question 2

True or false
Some RNAs are not translated into protein. The RNA is the active end product

Answer 2

True

Question 3

RNA polymerase or DNA polymerase?
1. Active in S phase
2. Exonuclease activity
3. De novo synthesis

Answer 3

1. DNA polymerase
2. DNA polymerase
3. RNA polymerase

Question 4

_____ DNA region that facilitates transcription initiation. ____ DNA region that signal transcription stop.

Answer 4

Promoter
Terminator

Question 5

Prokaryotes have one RNA polymerase called a _____. It is made up of the core enzyme plus a sigma factor

Answer 5

Holoenzyme

Question 6

Transcription factors are needed to access DNA in its _____ form.

Answer 6

Chromatin

Question 7

A typical RNA polymerase II promoter contains a ____ ____.

Answer 7

TATA box

Question 8

General transcription factors of RNA polymerase II all starts with ____ in their name and assemble in a step wise fashion to start transcription.

Answer 8

TF

Question 9

Eukaryotic transcript elongation is coupled with RNA processing. A 5’ _____ is added, ____ are removed, and a _____ is added at the 3’ end.

Answer 9

CAP
Introns
PolyA tail

Question 10

Different cell types contain the same set of genes but synthesis different sets of _____.

Answer 10

Proteins

Question 11

General transcription factors bind to ____ promoter sequences such as TATA box, BRE, and DPE.

Activators bind to _____ promoter sequences such as CAAT box, GC box.

Answer 11

Core
Proximal

Question 12

Activator proteins and repressor proteins bind to specific sequences in the ____ ____ ____.

Answer 12

Distal Promoter Sequences

Question 13

Gene regulator proteins read DNA on the ____ of the double helix, in the _____ groove.

Answer 13

Outside
Major

Question 14

Gene regulator proteins carry typical DNA binding motifs such as
1.
2.
3.

Answer 14

1. Helix turn helix motif
2. Zinc finger motif
3. Leucine motif

Question 15

The _____ _____ uses tryptophan as a ligand to repress genes in the operon of E. coli cells.

Answer 15

Tryptophan repressor (TRP)

Question 16

TRP repressor can only bind to the operator when it is associated with tryptophan. If there are low levels of tryptophan, the operon is ____. If high levels of tryptophan, the operon is ____.

Answer 16

On
Off

Question 17

There is dual control of the lac operon.
+glucose +lactose:
+glucose -lactose:
-glucose -lactose:
-glucose +lactose:

Answer 17

Operon is off
Operon is off
Operon is off
Operon is on

Question 18

_____ ____ are found in eukaryotic cells they are more complex than prokaryotic operon gene regulation. One gene can be controlled by_____ regulatory proteins.

Answer 18

Genetic switches
Dozens or more

Question 19

The typical order of events for _____ ____ are as follows: gene activator protein binds to chromatin, chromatin remodeling, covalent histone modification, additional activator proteins bound to Gene regulatory region, assembly of pre-initiation complex at the promoter.

Answer 19

Transcription initiation

Question 20

Gene ____ proteins bind DNA sequences named enhancers. They have a DNA binding domain and an activation domain.

Answer 20

Activator

Question 21

Repressor proteins often recruit histone ______ or histone ______ _____, in order to promote heterochromatin

Answer 21

Deacetylases
Methyl transferase

Question 22

______ _____ make DNA more accessible to the transcription machinery such as activators and repressors

Answer 22

HDAC inhibitors

Question 23

___ _____, for example actinomycin, block transcription elongation in prokaryotes and eukaryotes.

Answer 23

DNA intercalators

Question 24

antibiotics such as _____ bind only bacterial RNA polymerase

Answer 24

Rifampicin

Question 25

_____ ______: specifically inhibits RNA polymerase II. It is a common cause of fatal mushroom poisoning (death cap)

Answer 25

Alpha amanitin

Question 26

Answer 26

Review

Question 27

_____ _____ is used by cells to control mRNA stability, prevent mRNA translation, promote heterochromatin

Answer 27

RNA interference (RNAi)

Question 28

miRNA has a ____ and ____, similar to mRNA

Answer 28

CAP
PolyA tail

Question 29

______ reduces translation by transferring mRNA into P bodies and eventual degradation

Answer 29

Slicing

Question 30

Dicing uses the ___________ to rapidly degrade mRNA

Answer 30

RNA induced silencing complex (RISC)

Question 31

______ uses the microprocessor complex, Drosha-Pasha to cleave the polyA tail and CAP from mRNA

Answer 31

Cropping

Question 32

miRNAs often target _____ of mature mRNA

Answer 32

3’UTRs

Question 33

______ regulate essential mechanisms, such as embryonic development, cell and tissue, differentiation, carcinogenesis, etc.

Answer 33

miRNAs

Question 34

There are two general categories of interference RNAs.
1. ______ encode in our genome and often transcribed by RNA polymerase II, SSRNA precursor with stem loop structure
2. _______ generated from exogenous, have long dsRNA precursors

Answer 34

Micro RNAs (miRNAs)
small interfering RNAs (siRNAs)

Question 35

The goal of ________ is to block translation, and promote mRNA de stabilization/cleavage.

Answer 35

miRNA

Question 36

______ mostly mediate mRNA cleavage, and are produced in the cytoplasm by Dicer

Answer 36

siRNA

Question 37

siRNAs use ______ to promote histone, methylation DNA methylation and transcriptional repression

Answer 37

RNA induced transcriptional silencing complex (RITS complex)

Question 38

Abnormal miRNAs expression is linked to many diseases including:

Answer 38

psychiatric/neurodevelopmental disorders, abnormal heart, development, and heart disease, cancer, and diabetes

Question 39

Delivery of synthetic siRNA to target cells can knock down or up regulate genes involved in a disease. Use siRNA to block mRNA leading to _____. Use siRNA to block miRNAs leading to ________.

Answer 39

Gene silencing
Gene up regulating

Question 40

Answer 40

Review

Question 41

The main types of epigenetic control of gene expression are _____ and _____.

Answer 41

DNA methylation
Chromatin modifications