Can you tell me what exactly is gene expression ?

[Persefone]

Can you tell me what exactly is gene expression ? I think it is the expression of a gene, correct ?

By the way, I see my teacher usually sits in front of his computer, with a long page full of amino acids, I guess he might take it from somewhere's database, but do you know why people usually talk about gene database, bank. What do they do with it?
I don't think that teacher will like my curiosity, can you tell me something about what you did that is related to gene database...Thank

 

[kalladin]

A teacher who doesn't like students asking questions can't be a very good teacher ^^
I'm not very knowledgeable, but what I know of gene databanks is that it's a collection of all organisms' sequences. For example, in the bank you would be able to find Arabidopsis thaliana gene sequence. So when you do research and you sequence a part of a protein or something.. you get an amino acid sequence. You would use your sequence and compare it to the sequences found in the bank, and the bank would come up with matches with % conformities. So you would be able to find out what kind of organism that protein came from etc, etc.

And here's some stuff on gene expression: http://en.wikipedia.org/wiki/Gene_expression

Thank God for Wiki

EDIT: not "all organisms' sequences" but rather all sequences of organisms that have been sequenced

 

[detta]

Gene expression is just what you think, whether or not a gene is being transcribed. Many genes have different patterns of expression, for example some are expressed during different times of the cell cycle or only in certain cell types. An important little caveat is that it is transcriptional expression, not protein, so even though the mRNA is being made it doesn't necessarily mean that the protein is active or even made (it could be degraded).

There are lots of gene databases. The major one used is NCBI. If you go to pubmed.org and and choose gene in the little pull down window and then type a gene into the search box, it will access the database and pull out lots of information on that gene. Using NCBI you can get lots of information.

By the way, I'm not sure what your teacher does but most really love to talk about what they are studying, so although you know your teacher better than I do, for all I know he/she could be a jerk, when it comes to what they are interested in they usually can't shut up so it wouldn't hurt trying to ask.

peace

 

[quasi426]

Gene expression means that the gene on the DNA is getting expressed to do the job its supposed to do. The most common way a gene is expressed is from DNA to mRNA to Protein. If you only get mRNA then you may not be expressing the gene. Other genes for rRNA and tRNA and other RNA molecules may not get translated into a protein and thus the RNA form is the final form of expression.