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Drosophila: Gene knockout using a transposon technology - Why do you get a gene expression? Other methods to knockout a gene? (Oct/16/2007 )

"You have just started your MSc project working with Drosophila, the fruit fly. Your former colleague has done a gene knockout using a transposon technology. Your task is to further characterise this new strain that is supposed to have sepia eyes but to your surprise they are not. Try to explain why? And suggest a method which could be more successful than the transposon strategy?"

Can't find any info in my course litterature, handouts from lectures and searching on Google gave me nothing. Please give me some clues or ideas. I'm really stuck with this one.

Apparently there is a biological/genetical explanation to why you get a gene expression anyway. What is that explanation? And what other methods could you use if you really want to knockout this quality?

Please, please help me. I'm stuck.

-Genetic Girl-

Apparently it has something to do with genefamilies...

-Genetic Girl-

I assume that you will have covered some of this in your course ( I can't imagine that they're that evil)- the information is there in your question. Have you had lectures on transposons? what do you know about them? what have they been used for? what are the advantages and disadvantages of this?
Eye colour in Drosophila- what is the genetic basis for eye colour in Drosophila? If it has to do with gene families- what do you know about gene families in terms of chromosomal locations and expression?

As to your other question- Its a big answer as to why and how you get gene expression- its very complicated and tightly regulated. Other methods for knocking out gene expression- there are a few- I assume you've heard of gene knockout mice? think about what happens there (you can find this information in text books and on the internet).

I hope that helps. Good Luck

Lost in the lab

-lost in the lab-

Yes, we've had some lectures on transposones, but not that detailed. I know that:

Transposons are sequences of DNA that can move around to different positions within the genome of a single cell, a process called transposition. In the process, they can cause mutations and change the amount of DNA in the genome. Transposons are also called "jumping genes", and are examples of mobile genetic elements. Transposons are very useful to researchers as a means to alter DNA inside of a living organism.

Advantages with transposon approach:
•Simple. Can generate large number of insertions.
•Relatively inexpensive.
•Can be used to find genes.
•Get many alleles
•Can follow expression and tag proteins

Disadvantages with transposon approach:
•Biased. Hard to hit all genes.

I barely know anything at all about Drosophila. All I know is that Drosophila has four pairs of chromosomes: the X/Y sex chromosomes and the autosomes 2,3, and 4. The wild type Drosophila has red eyes and if a Drosophila has sepia eyes it has something to do with a defect in the PDA synthase. Since this is my first course ever i genetics I don't have much knowlegde about it.

I would really appreciate some more info from someone who is good at this. Thank you.

-Genetic Girl-

QUOTE (Genetic Girl @ Oct 24 2007, 09:27 AM)
I would really appreciate some more info from someone who is good at this. Thank you.




I'm confused- why isn't the stuff you wrote about the advantages and disadvantages of transposons in this link? huh.gif

Anyway, I got your message- reply is winging its way to you.

-lost in the lab-

QUOTE (Dominic @ Oct 24 2007, 04:11 PM)
QUOTE (Genetic Girl @ Oct 24 2007, 09:27 AM)
I would really appreciate some more info from someone who is good at this. Thank you.


excl.gif Hey! I didn't mean it that way. Lost in the lab has been very helpful and I think I finally got it biggrin.gif

-Genetic Girl-

Awww Shucks! blush.gif

I hope so.

-lost in the lab-