Cell signalling

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Pit2190
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Cell signalling

Post by Pit2190 » Thu Oct 21, 2010 5:03 am

Alright, I've been trying to figure this out for some time now and cannot find an answer for it.

The situation I am supposed to be looking into is this:
A person engineers a set of genes, each encoding a protein with a pair of sequences that specify two different compartments. The protein is normally cytoplasmic and contains no sorting signal. Assuming that the genes are both expressed in the cell, which signal would win out and where would the protein end up.

I have no idea how to really go about this and help would be greatly appreciated.

Ex: A protein has a signal squence for import into the nucleus and a signal sequence for import into the ER. Which signal would win out and where would the protein end up.

I am not looking for an answer to this example, just some guidance and understanding of how this all works.

Thanks in advance!

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JackBean
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Post by JackBean » Thu Oct 21, 2010 6:00 am

if you got that in school, your teacher is really stupid, because that need to be seen experimentally.
Anyway, the question is, whether these signals will work at all. For example, for nuclear targeting there are like 4 AAs in the very C-end, so if are they covered with something else, it probably won't work.
Also, if you had two signals in a row in the N-end, probably the first one will direct the protein.
http://www.biolib.cz/en/main/

Cis or trans? That's what matters.

Pit2190
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Post by Pit2190 » Thu Oct 21, 2010 7:06 am

Hmm... I'm not sure enough information is given to determine which signal would be first, and not to discredit your answer, but I do not believe my professor would give a question that couldn't be answered with experimental data. Is there some sort of prioritization when it comes to having multiple signals, or does the fact that the protein is normally cytoplasmic without a sorting signal factor in?

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JackBean
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Post by JackBean » Mon Nov 01, 2010 8:48 am

if it has normaly no signal, then the new one will be superior of course (you can imagine any protein with one signal as a protein being without signal, but engineered to have one:), anyway, if we were thinking only about the two N-terminal signals, then probably the first one in sequence will be superior...
http://www.biolib.cz/en/main/

Cis or trans? That's what matters.

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