SNAREs

Question 1

What is membrane fusion used for?

Answer 1

• Synaptic vesicle fusion
• Secretory granule fusion
• Intracellular transport of proteins between organelles.

Question 2

What cleaves VAMP?

Answer 2

Tetanus and Botulinum

Question 3

What did Biochemical reconstitution show about membrane fusion?

Answer 3

Radioactive sugars used to show glocalization and measure vesicle budding and fusion.

Question 4

What are the SNARE hypotheses?

Answer 4

• SNAREs for each transport step
• SNAREs provide specificity
• SNAREs drive membrane fusion

Question 5

How many SNAREs are encoded in the human genome?

Answer 5

38

Question 6

What is the structure of a SNARE complex?

Answer 6

VAMP from vesicle.
Syntaxin and SNAP35 in target membrane

Question 7

How do the SNARE domains connectt?

Answer 7

Zip up in a parallel coiled coil

Question 8

What is a Q SNARE?

Answer 8

Syntaxin and SNAP25.
There are 3 coils, as SNAP25 provides 2.

Question 9

What is an R SNARE?

Answer 9

VAMP.
There is 1 coil.

Question 10

How specific are SNAREs?

Answer 10

Only 3Q:1R SNAREs fuse.
Some SNAREs can interchange what they fuse with, but most fuse with the appropriate membranes.

Question 11

What are the common features of SNAREs?

Answer 11

• Small (14-40 kDa)
• At least one SNARE motif
• Generally C terminal anchored

Question 12

Why is hydrolysed ATP not required for fusion?

Answer 12

Coiled coil gives energy for fusion.

Question 13

What does NSF do?

Answer 13

NSF recycles SNAREs after fusion.