Intracelluar membrane trafficking part 2

Question 1

What are Snare proteins ?

Answer 1

They catalyse membrane fusion reactions in residue transport
35 different snares in animal cell associated with particular organelle

These are found on vesicle membranes usually found on target membrane

Question 2

What is V snare is a single ? What T snare ?

Answer 2

Single polypeptide chain

T -SNARE composed of three proteins

V- SNARE AND T - SNARE have characteristics helical domain of other forming a four helix bundle .Resulting trans -SNARE complex looks membrane together

The trans -SNARE complexes ,catalyse membrane fusion by using the energy that is freed when interacting helices wrap around each other .

In cells other proteins are reduced by fusion .

Question 3

What is the aim of the Rab Proteins ?

Answer 3

Regulate availability of sNARE proteins their are effective trigger release of SNARE inhibitory proteins ,

sNARE proteins are concerned and activated in the correct location on the membrane .

Vesicle transport , in order for it to operate normally , must incorporate rate of snare and rab proteins

Question 4

Dissociations of sNARE complex ?

Answer 4

After a V -sNARE are and T -sNARE have mediated the fusion of transport vesicle with a target membrane .

NSF binds to the sNARE protons complex not protein and with the help of accessory proteins , hydroylase ATP so SNARE can be pulled away .

This process is crucial to ensure appropriate membrane fuse

Most sNARE proteins In cells have participated in multiple rounds of vesicle transport and present In membrane as stable complexes.

Question 5

What does the crucial proteis Nsf do ?

Answer 5

Cycles between membranes and the cytosol and catalyses disassemble process uses energy of ATP hydrolysis

Question 6

What other processes are important for membrane fusion?

Answer 6

Plasma membrane of a sperm or egg fuse during fertilization

Membrane fusion is catalysed viral fusion proteins .

Proteins have crucial role in permitting entry of enveloped virus which have lipid bilayer has membrane coats

Question 7

Viruses /Influensa ?

Answer 7

First enter cell through receptor mediated endocytosis

Viral fusion proteins and sNare promote lipid bilayer fusion in similar ways .