Case 5 - what happens when cells go nuclear?

Question 1

What are the classes of nuclear receptors?

Answer 1

• class I: steroid receptor
• Class II: RxR receptors
• Class III: homodimeric orphan receptors (no ligand discovered yet)
• Class IV : momeric orphan receptors

Question 2

What are the structural components of NR’s?

Answer 2

• N-terminal domain (activates AF-1)
• DNA binding domain
• hinge region
• ligand binding domain

Question 3

What types of ligands can bind to the NR’s?

Answer 3

• lipophilic molecules
• steroid hormones
• Thyroid hormones
• retinoids
• Bile acids
• fatty acids

Question 4

How is activity of NR’s regulated?

Answer 4

1. ligand- dependent transcriptional activation
2. ligand- independent active repression
3. ligand-dependent transrepression

Question 5

What is a consensus sequence?

Answer 5

a sequence of DNA/RNA protein that represents aligned related sequence

Question 6

What do you need to notate when in a row of sequences, you only have pyrimidines?

Answer 6

Pyrimidines are C, U and T. You need to notate Y

Question 7

What do you need to notate when you only have purines in a row of sequences

Answer 7

purines are A and G. You need to notate R

Question 8

What is PPAR

Answer 8

peroxisome proliferator activated receptors alpha. plays important role in fatty acid metabolism