ZIMA questions lecture 5 Flashcards Preview

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Flashcards in ZIMA questions lecture 5 Deck (17)
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1
Q

________: proteins are transported by endosomes from the ER to the PM or lysosomes aka outward

_______: proteins are transported from PM and delivered to endosomes and lysosomes - inward

_______: balancing in the opposite direction, bringing membrane and selected proteins to compartment of origina

A

Exocytosis

Endocytosis

Retrieval Pathway

2
Q

Vesicular transport is mediated by _______

Before the vesicles fuse with the membrane they______

A

Vesicular transport is meadiated by coated vesicles

Before the vesicles fuse with the membrane they discard their coat

3
Q

What are the two main functions of the coat around vesicles

A

Two main functions of the coat:

  1. it concentrates specific membrane proteins in a specialized patch
  2. it forms the vesicle
4
Q

Clathirin coated vesicles are involved in____

COP I and COP II are in volved in _____

A

Clathirin: ENDOcytosis

COPI and COPII: EXOcytosis

5
Q

______ is the major protein of coated vesicles

Structure:

A

Clathirin is the major protein of clathirin coated vesicles

Clathirin forms a triskelion (six subunits)

6
Q

______ binds clathirin coat to the cargo receptors

A

ADAPTOR proteins bind clathirin to the cargo receptors (it goes cargo protein –> receptor–> adaptor protein–> clathirin)

7
Q

Without an adaptor protein will the vesicle form?

A

NO without an adaptor protein the vesicle cannot form

8
Q

__________ have important regulatory function in vesicular trafficking.

A

Phosphoinosites (PIPs) have important regulatory function in vesicular trafficking.

PIPs can undergo phosphorylation and dephosphorylation

9
Q

The distribution of different PIPs varies from organelle to organnele

The PIP binding proteins help regulate_____

A

The PIP binding proteins help regulate vesicle formation and transport.

10
Q

What structure plays an important ole in PINCHING off of clathirin vesicles

A

PINCHING off of vesicles: dynamin

dynamin uses GTP to squeeze bilayer and pinch it off

11
Q

Explain how vesicles are uncoated:

After releasing the vesicle loses its clathirin coat:

  1. ________ that are co-packaged into vesicles depletes, weakining the binding of adaptor protein and diassembles clathirin
  2. Additionally, the hydrolysis of ___ on ____ causes the coat to diassemble
  3. _____ protein acts as the uncoating ATPase
A
  1. PIP phosphotases deplete phosphates from the membrane, weakining the binding of adaptor proteins and diassembles clathirin
  2. Additionally, the hydrolysis of GTP in Sar1 protein causes the vesicle coat to disassemble
  3. Hsp 70 chaperone protein acts as uncoating ATPase
12
Q

What structure directs the vesicles to specific spots on the target membrane?

A

RAB proteins direct vesicles to specific spots on the target membrane

13
Q

What MEDIATES the fusion of the lipid bilayer

A

SNARE MEDIATES fusion

14
Q

What protein is the TETHERING protein to the target membrane

A

RAB EFFECTORS tether the vesicle to the membrane

15
Q

V snare vs T snare

transSNARE complex

A

V snare (single chain)

T snare (many chains)

V and T come together to form a transSNARE complex

16
Q

What protein diassembles the SNARE complex?

A

NSF protein diassembles the SNARE complex

17
Q

HIV first binds with the _____ protein on the target cell. The viral ____ protein mediates the interaction.

Then ___ receptor interacts to release the HIV fusion protein.

A

HIV first binds to the CD4 protein on the surface of the target cell. The viral gp120 protein, which is bound to the HIV fusion protein mediates this interaction. Then, chemokines receptor interacts with gp120 to release the HIV fusion protein.