Advantages and disadvantages with transposable elements? - (Oct/22/2007 )

Having some trouble with a question where you should describe a forward and a reverse genetics technique briefly. I picked transposable elements for the forward genetics and RNAi as a reverse genetics technique. I've described them briefly but would like to know what you think. Is it enough? What more should I put in?


"Transposable elements:
Transposable elements is a forward genetics technique used to alter gene activity. A cell line that contains a transposable element capable of transposition is generated. If the transposable element moves into your gene, it will create mutations which will disrupt function, and hopefully create a phenotype. To increase the probability that the gene of your interest will be affected you could choose a cell line where the transposable element is already near your gene. You then search for the phenotype that you are interested in and once you find it you can identify the mutated gene.

Advantages with transposable elements:
When creating mutations there is only a single transposable present, and therefore the number of second site mutations are low. This will save time when doing backcrossing.

Disadvantages with transposable elements:
Transposable elements are rather large and therefore not preferable to work with when doing fine detail analysis (single nucleotides). Other disadvantages include merely transient siRNA expression and low and variable transfection efficiency.


RNA interference:
RNA interference (RNAi) is a method where you introduce double-stranded RNA in a cell or organism to silence a specific gene expression. It’s a common mechanism of post-transcriptional gene silencing and it works based on the ability of double-stranded RNA (dsRNA) to recognize and degrade complementary single-strand RNAs. The dsRNA then destroys that particular mRNA, and thereby diminish or abolish the gene expression. RNAi is a powerful tool to silence the expression of genes and analyze their loss-of-function phenotype. The technique has proven effective in Drosophila, Caenorhabditis elegans, plants and in mammalian cell cultures.

Advantages with RNAi:
RNAi have been shown to work in a similar way in all metazoans, and it has been proven to be applicable to many organisms and has been used to generate a wide variety of loss-of-function phenotypes. It’s also a simple, inexpensive and systematic method.

Disadvantages with RNAi:
One difficulty in using RNAi as a reverse genetic technique is that throughput is limited by the ability to deliver siRNAs to target loci. It is also labor intensive, can give equivocal results, and can be unsuitable for isolating mutants that have lethal or sterile phenotypes."


Thanks.

"single transposable present" - typo?

apart from that to turn it from a ok answer to a good one (or good to great?) you need to include examples eg cell line names
to do this you really need the name of your transposable element too - so look up one on the net and use it as a rolling example (ie taking bits from it as you go along) dont forget to reference the paper you used at the end. this way you dont have to be so vague and your answer has the look of a pro

in the second half of the answer you are closer to this as you do use examples (but not quotes) and it helps it all flow a little easier

(cant be much help with the science bit as its so long since i did stuff like this i've forgotten it all)

good luck

dom