From: Robert J. Bradbury (bradbury@aeiveos.com)
Date: Thu Jan 16 2003 - 09:16:17 MST
On Thu, 16 Jan 2003, Damien Broderick wrote:
> I do hope this doesn't mean that tailored xenotransplants will end up
> knocking out important genes in the patients.
Sorry, I probably should explain how RNA interference works...
It turns out that eukaryotic cells have an interesting defense
against double-stranded RNA (which they would normally consider
to be from a viral source) that causes them to destroy or suppress
said RNA (waves hands here). It also turns out that in C. elegans,
they appear to take up the RNA from the E. coli they consume
(more hand waving?). Thus if you engineer an E. coli to produce
RNA complementary to a specific gene in C. elegans and then feed
it to the C. elegans, the combination of these processes ends up
producing double stranded RNA for the gene of focus and the cells
end up destroying that specific mRNA effectively creating a knock-out
for the gene. This you move the genetic engineering for a knock-out
from the C. elegans to the E. coli which is much easier and faster.
I doubt it would work in higher level animals, though I think
variants using a gene therapy approach to produce the complementary
RNA may work.
Please note lots of hand waving -- if someone wants to do some
digging and find the real sources in PubMed (or Google) they
are more than welcome to. I wouldn't be surprised if the people
that came up with this method win a Nobel prize. It may end up
being a contribution of the order that PCR was.
Robert
This archive was generated by hypermail 2.1.5 : Tue Jan 21 2003 - 17:10:21 MST