Protein Transport 2

Question 1

Vesicular binding steps

Answer 1

Packaged with G protein rAB. It hooks tethering protein, bringing vesicle close enough for v-snare to fuse with t-snare

Question 2

Snare complex dismantled by what?

Answer 2

NSF/SNAP complex

Question 3

Pinocytosis

Answer 3

Fluid and other macromolecules ingested non specifically. Uncoated membrane invaginations

Question 4

Receptor mediated endocytosis

Answer 4

Large molecules, eg ldl. Cargo mol bind to acceptor, changing receptor to attract adaptin proteins. Adaptin recruits clathrin. Makes triskelion. Dynamin pinches off

Question 5

Caveolin mediated endocytosis

Answer 5

Use integral protein caveolin instead of peripheral clathrin. Transcytosis gets fluid from one side of cell to another

Question 6

Phagocytosis

Answer 6

Membrane engulfs material. Uses actin.

Question 7

Material flow in phagocytosis

Answer 7

Early endosome, multivesicular compartment, late endosome, endolysosome, lysosome

Question 8

Early endosome.

Answer 8

Slightly acidic, ligand and receptor separate. Receptor returns to membrane, ligand to multivesicular body

Question 9

MV bodies

Answer 9

Travel on microtubules with dynein. From early to late

Question 10

Late endosome

Answer 10

Lower pH, 5. Some parts become lysosome

Question 11

Constitutive secretion

Answer 11

Vesicle formed at trans golgi with dynamin, go to surface with kinesin. Then myosin. Need no external signal. Maintains plasma membrane

Question 12

Regulated secretion

Answer 12

Products stored in vesicle, only released when signaled

Question 13

Passive transport

Answer 13

No energy needed, down gradient. Carrier or channel proteins

Question 14

Channel types

Answer 14

Voltage gated, ligand gated, mechanically gated, ungated

Question 15

Carrier types

Answer 15

Uniport, symport, antiport. Can be passive or active

Question 16

Active transport

Answer 16

Needs atp. Against gradient.