Lysosomes

Question 0

What is I cell disease also known as?

Answer 0

Mucolipidosis type 2

Question 1

Why are hydrolases excreted in I cell disease?

Answer 1

Absence of M6P for endosome retrieval

Question 2

How are hydrolases targeted to the Lysosome in normal function?

Answer 2

GNPTA gene for N-acetylglucosiminidase-1-phosphotransferase modifies mannosylated glu and to produce M6P

Question 3

What autosomal characteristic does I cell disease have?

Answer 3

Recessive

Question 4

Which disease is caused by accumulation of glycogen?

Answer 4

Pompe disease

Question 5

Which enzyme is affected by the recessive mutation in pompe’s disease?

Answer 5

Alpha-D-glucosidase

Question 6

Fabry disease has mutations in which gene?

Answer 6

Beta-galactosidase

Question 7

Deposition of what molecule causes fabry disease?

Answer 7

Globotriaosylceramide (Gb3)

Question 8

What function does mutated Galactosidase not have?

Answer 8

No cleavage of terminal galactose

Question 9

What are the clinical symptoms of fabry disease?

Answer 9

Deposition of glycolipid globotriaosylceramide in arteries

Question 10

How many carbons are in a sialic acid?

Answer 10

9

Question 11

ISASD has inability to do what?

Answer 11

Transport sialic acid products out of Lysosome

Question 12

Is SALLA more or less severe than ISASD?

Answer 12

Less

Question 13

What is the structure of lysosomes?

Answer 13

200-400nm
spherical
pH4.5-5 maintained by vATPases
45 hydrolases

Question 14

How are molecules degraded by lysosomes?

Answer 14

Endocytosis/Autophagy/Phagocytosis
Maturation to late endosome
Mannose-6-Phosphate receptors target lysosomes
Fusion through double membrane 
Degradation

Question 15

What other functions are lysosomes involved in?

Answer 15

Repair of plasma membrane

Leakage of cathespins into cytoplasm during apoptosis

Question 16

Which lysosome diseases can be treated?

Answer 16

Fabry, Pompe