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Old 03-17-2015
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Default Cell trafficking

Can someone please explain to me or provide me with a video that simplifies cell trafficking?

Also, please explain to me the different vesicular trafficking proteins; I do not seen to understand the way FA mentions them. What is their purpose in the human body?

thanks a lot!!
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Old 03-17-2015
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You don't need to know many cell-trafficking things. I'll try to list the most important ones:

Dyenin, and Kinesin. Highway for transport of things.

Dyenin ->For Retrograde transport. Toxins/viruses gain access to the central nervous system via this pathway (i.e injury at the periphery, viruses/toxins climb on the dyenin actin system, and go all way to the cell body and access the CNS. Mechanism in tetanus and many other viruses/neurotoxins)

Kinesin -> For Anterograde transport. Especially board relevant after nerve injury. The ribosomes and other important nutrients climb on these tracks and get to the site of the lesion, i.e. away from the cell body and towards the axon. Utilized in Wallerian degeneration, and this is how neurotransmitters are generally transported out from the cell body all the way to the nerve terminals. It also includes the transport of mitochondria, ribosomes and other important things.

The other important ones are the transport proteins that direct things to the outside or to within the cell.

-If a ribosome is making a new chain, and the first few amino acids are very hydrophobic, that is a signal right there that this needs further processing in the RER. The SRP recognizes these initial hydrophobic amino acids, and transfers the growing chain directly into the RER. Hence, if there is any problem with SRP, chains will accumulate in the cytoplasm and RER will be empty.

-After the ribosome, the vesicles need to either go outside or to lysomes. This next step is taken care by the Golgi. In order to go to Golgi, there is a trafficking protein called COPII. If there is an error in COPII, everything accumulates in RER and Golgi is empty.

-In the Golgi, if a thing is destined to go to Lysosomes, it is tagged with Mannose-6-Phosphate residues in the Golgi. If this process fails, lysosomes are empty (I-Cell disease). The vesicles itself is taken to the Lysosomes via Clarithin.

-Things that are phagocytosed and picked from outside are taken in as vesicles. They are then taken to Golgi. Most of them need further processing, and are taken back to RER via COPI. Deficiency in COPI will prevent the breakdown of phagocytosed material.

These are the most important board relevant. Hope its clear and they help!
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Old 03-18-2015
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Quote:
Originally Posted by Smashingdude View Post
You don't need to know many cell-trafficking things. I'll try to list the most important ones:

Dyenin, and Kinesin. Highway for transport of things.

Dyenin ->For Retrograde transport. Toxins/viruses gain access to the central nervous system via this pathway (i.e injury at the periphery, viruses/toxins climb on the dyenin actin system, and go all way to the cell body and access the CNS. Mechanism in tetanus and many other viruses/neurotoxins)

Kinesin -> For Anterograde transport. Especially board relevant after nerve injury. The ribosomes and other important nutrients climb on these tracks and get to the site of the lesion, i.e. away from the cell body and towards the axon. Utilized in Wallerian degeneration, and this is how neurotransmitters are generally transported out from the cell body all the way to the nerve terminals. It also includes the transport of mitochondria, ribosomes and other important things.

The other important ones are the transport proteins that direct things to the outside or to within the cell.

-If a ribosome is making a new chain, and the first few amino acids are very hydrophobic, that is a signal right there that this needs further processing in the RER. The SRP recognizes these initial hydrophobic amino acids, and transfers the growing chain directly into the RER. Hence, if there is any problem with SRP, chains will accumulate in the cytoplasm and RER will be empty.

-After the ribosome, the vesicles need to either go outside or to lysomes. This next step is taken care by the Golgi. In order to go to Golgi, there is a trafficking protein called COPII. If there is an error in COPII, everything accumulates in RER and Golgi is empty.

-In the Golgi, if a thing is destined to go to Lysosomes, it is tagged with Mannose-6-Phosphate residues in the Golgi. If this process fails, lysosomes are empty (I-Cell disease). The vesicles itself is taken to the Lysosomes via Clarithin.

-Things that are phagocytosed and picked from outside are taken in as vesicles. They are then taken to Golgi. Most of them need further processing, and are taken back to RER via COPI. Deficiency in COPI will prevent the breakdown of phagocytosed material.

These are the most important board relevant. Hope its clear and they help!

Thank you very much, this makes things simpler.

Just one last question if you do not mind:

you explained COPI/II, what about clathrin? how is it relevant from a pathophysiological point of view?
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