Nucleo-Cytoplasmic Exchange

ID #2002

Since the shuttle protein has a NES and NLS sequence, when its in the cytoplasm, can it bring another molecule without an NLS into the nucleus if it binds to it and an importin binds to it?

We don't have to worry about these "intermediate" shuttle proteins bringing anything back with them into the nucleus, because they're only set up to recognize one thing, and they're not going to find it out in the cytoplasm. I'm not saying that there aren't RNAs out in the cytoplasm, I'm suggesting that they won't find them. Once a ribosome gets on a mRNA molecule, it's game on. Polysome formation will essentially prevent any "coat" proteins from finding what they're looking for, and in the meantime, an Importin will find that shuttle protein and bind to it, bringing it back into the nucleus.

Print this record Print this record
Send to a friend Send to a friend
Show this as PDF file Show this as PDF file
Export as XML-File Export as XML-File