Intracellular Membrane Transport

Question 1

The major organelles involved in intracellular tranpsort

Answer 1

The ER and the Golgi Apartus

Question 2

The function of the ER

Answer 2

Protein production in ribosomes

Question 3

The main coat proteins we need to know

Answer 3

• Clathrin
• COPI
• COPII

Question 4

The function of clathrin

Answer 4

Binds to coat plasma membrane and between endosomes and the Golgi; Links actin and cytoskeleton

Question 5

The function of COPI

Answer 5

Secretory pathway; bud from the Golgi

Question 6

The function of COPII

Answer 6

Secretory pathway; bud from the ER

Question 7

Adaptor proteins (Sec, AP2)

Answer 7

Alter conformations when it binds to a certain phosphoinositide which exposes it for cargo receptors

Question 8

GTPases (Sar)

Answer 8

Control the assembly of COPI and COPII coats on Golgi and ER and clathrin on endosomes. Sar specifically controls assembly of COPII at the ER membrane

Question 9

Phosphoinositides

Answer 9

Marks organelles and membrane domains with (de)phosphorylation events

Question 10

Rab/Rab effectors

Answer 10

Guide transport vesicles to their target membranes and direct the vesicles

Question 11

SNARE

Answer 11

Regulators that mediate the fusion of lipid bilayers

Question 12

GAP/GEF

Answer 12

GAP’s are GTPase activating factors that inactivate proteins by triggering the hydrolysis of GTP. GEF’s activate by catalyzing the exchange of GDP for GTP.

Question 13

Dynamin

Answer 13

Pinches off clathrin coated vesicles with a binding domain powered by GTP hydrolysis