Blood clotting

Question 1

What is the difference between normal and abnormal prion protein?

Answer 1

Normal (PrP^c) has many alpha helical regions and relatively soluble

Abnormal (PrP^Sc) has many beta-pleated sheet regions and insoluble

Question 2

Outline the structure of fibrinogen

Answer 2

46nm

alpha-helical coiled coil

Question 3

What formation do fibrinogen form?

Answer 3

Half-staggered array of fibrin monomers

Question 4

What causes fibrinogen to convert to fibrin?

Answer 4

thrombin

It cleaves fibrinopeptides A and B

Question 5

What causes the cross linking of fibrin?

Answer 5

Glutamine and Lysine N terminal polymerising by transglutaminase

NH4+ is by-product

Question 6

Outline charge distribution of fibrin

Answer 6

Negative arms, positive core covered by negative fibrinopeptides

Question 7

Structure of plasminogen activators?

Answer 7

Fibrin binding-Kringle 1-Kringle 2-Serine protease

Question 8

What are features of N-terminal sequences?

Answer 8

13-36 residue length

Amino-terminal of signal sequence have >1 basic residue (arg,lys)

Hydrophobic region 10-15 residues long
-Alanine, Luecine, Valine, Isoleucine , Phenylalanine

substitution of Hydrophobic region destryos the directing activity of the signal sequence

Question 9

Outline membrane asymmetry (fusing) during vesicular transport

Answer 9

ER > Vesicle budding from ER > Golgi complex > Vesicle > Fusing vesicle > Plasma membrane

Question 10

Outline biosynthesis of mannose-6-phosphate

Answer 10

1) Mannose residue
e: phosphotransferase
r: UDP-GlcNAc > UMP

2) ????
e: Phosphodiesterase
r: H20 > GlcNAc

3) Mannose 6 phosephate residue