Roni's lecture

Question 1

What are transcription factors?

Answer 1

These are proteins involved in converting or transcribing DNA to RNA.

Question 2

How is DNA, RNA and Protein synthesized?

Answer 2

DNA is synthesized via DNA replication
RNA is synthesized via Transcription
Protein is synthesized via Translation

Question 3

What does transcription and translation work?

Answer 3

Transcription uses RNA polymerase and transcription factors

Translation converts DNA to RNA to a Protein

Question 4

What does RNA polymerase 1 do?

Answer 4

It transcribes ribosomal RNAs which are essential for translation.

Question 5

What does RNA polymerase 2 do?

Answer 5

It transcribes the majority of eukaryotic genes for example mRNA to a protein

Question 6

What does RNA polymerase 3 do?

Answer 6

It transcribes a variety of RNAs such as 5s pre-rRNA, tRNA and snRNA.

Question 7

What are transcription factors?

Answer 7

They are proteins that bind to DNA and help recruit appropriate polymerase which helps control the rate of transcription of genetic material from DNA to RNA.

Question 8

How do transcription factors work?

Answer 8

They bind to DNA regulatory sequences and help recruit cofactors such as activators and coactivators.

Question 9

What are ACTIVATORS?

Answer 9

They are regulatory proteins bind to DNA at distant sites which is known as enhances.

Question 10

What are COACTIVATORS?

Answer 10

These are transcription factors that transmit signals from activator proteins to general factors.

Question 11

What are general factors and what do they do?

Answer 11

They are transcription factors that places RNA polymerase at the start of coding sequence and releases them to initiate transcription.

Question 12

What are the examples of steriods?

Answer 12

Sex hormones and corticosteriods

Question 13

What is the primary function of the estrogen?

Answer 13

It helps for the development of secondary female characteristics such as the breast and menstrual cycle.

Question 14

What are the effects of estrogen on bone?

Answer 14

It provides vitamin D and calcium

Question 15

What are the effects of estrogen on the liver?

Answer 15

It increases hepatic production of binding protein
It helps increase good cholesterol HDL
It helps decrease bad cholesterol LDL

Question 16

What are the effects of estrogen on the heart?

Answer 16

Helps prevent atherosclerosis

Question 17

What are the effects on estrogen on the brain?

Answer 17

It protects against nerve damage
It delays memory loss
helps nerve growth

Question 18

what are the two types of estrogen receptors and give examples of each?

Answer 18

Alpha for example breast cancer cells, endometrium , ovarian stoma cells
Beta for example brain, heart, kidney and lung

Question 19

The two estrogen receptors are located on the same chromosome.TRUE OR FALSE?

Answer 19

FALSE

Question 20

ER(a) and ER(b) have different tissue distributions and transcriptional regulatory effects on target gene. TRUE OR FALSE?

Answer 20

TRUE

Question 21

Estrogen enters all cells? TRUE OR FALSE

Answer 21

TRUE

Question 22

What are the harmful effects of estrogen on breast and uterus?

Answer 22

Increases risk of cancer in both

Question 23

How does cancer arise?

Answer 23

It arises from DNA mutations in cells

Question 24

How do mutations occur?

Answer 24

Can be heredity
Can be due to spontaneous errors in DNA replication
Can be due to chemicals/radiation

Question 25

What does SERMs stand for?

Answer 25

Selective estrogen receptor modulators

Question 26

Certain antiestrogen drugs are not pure antagonists but rather mixed agonist/antagonist.TRUE OR FALSE?

Answer 26

TRUE

Question 27

The ability of the ER to interact with other transcriptional cofactors depends on the structure of the ligand that is bound to the receptor. TRUE OR FALSE?

Answer 27

TRUE

Question 28

How do ER antagonists in breast tissue work?

Answer 28

They inhibit the estrogen dependent growth of breast cancer cells

Question 29

How do partial ER work in endometrium and bone?

Answer 29

They stimulate growth

Question 30

How does tamoxifen work?

Answer 30

It inhibits breast cell proliferation but stimulates cell growth in the endometrium

Question 31

What are the positives and negative aspects of tamoxifen when used as an anti -breast cancer drug?

Answer 31

It reduces risk of cancer It increases blood clots
It decreases LDL It increases chances of
uterine cancer
It strengthens bone

Question 32

What is considered to be an ideal SERMs?

Answer 32

It decreases LDL
decreases blood clots 
strengthens bone
reduces chances of breast cancer and uterine cancer 
it reduces hot flashes

Question 33

What are the positive aspects of Raloxifene?

Answer 33

Reduces chances of breast and uterine cancer
strengthens bone
Causes fewer blood clots than tamoxifen
reduces LDL and increases HDL

Question 34

What are the negative aspects of Raloxifene?

Answer 34

causes hot flashes
causes leg cramps
causes birth defects (teratogenic)
causes blood clots

Question 35

Describe the antagonist activity of Raloxifene?

Answer 35

It reduces risk of breast and endometrium cancer

Question 36

What are the agonist effects of Raloxifene?

Answer 36

It decreases bone resorption and delays the progression of bone loss so can therefore be used to treat osteoporosis.

Question 37

What is clomifene and Where is it located?

Answer 37

It is a ER in the hypothalamus and the anterior pituitary

Question 38

How does clomifene act as an antagonist?

Answer 38

It results in a relief of negative feedback inhibition is imposed by endogenous estrogen, it increases GnRH which causes ovulation.

Question 39

How does clomifene act as a partial ER agonist?

Answer 39

In the ovaries it acts causes ovulation and is used to treat infertility