h a l f b a k e r yThe Out-of-Focus Group.
add, search, annotate, link, view, overview, recent, by name, random
news, help, about, links, report a problem
browse anonymously,
or get an account
and write.
register,
|
|
|
So, pet fish modified to be permanently fluorescent
by
genetic means already exist, they are called GloFish.
These are pretty good, I've got some. I particularly
like
the red ones, which are expressing red fluorescent
protein
(RFP) throughout all their tissues. However, they
could
have done so much better, in addition to the stable,
cytosolic RFP I think the addition of a muscle-targeted
pericam (FlashPericam would do...) would really spice
things up. So, what this would achieve is that the
fish
would be red fluorescent all the time, however when
it
swims about in the pleasing manner that fish are wont
to
do, it would use series of coordinated muscle
contractions.
Now, muscle contraction is secondary to a large
increase
in
cytosolic calcium concentration, this would make the
cytosol-located pericam go from not-very-fluorescent-
at-
all
to -really-quite-fluorescent-indeed, meaning the fish
would
have some very pleasing green flashes down the sides
as
they swam. There. GloFish, only much better.
(?) GFP-based Genetically Encoded Calcium Sensors:
http://www.riken.go...df/No_49/49_055.pdf [bs0u0155, Dec 27 2011]
GloFish
http://www.glofish.com/ [bs0u0155, Dec 27 2011]
[link]
|
|
//No annotations?// What's to say? It's just a good
idea, that's all. |
|
|
Midnight In The Fishtank Of Good And Evil. |
|
|
I gave it a bun based on innovativeness. |
|
|
No clue if it would work so... so, just skip this anno, go on to the next one and pretend I haven't said anything at all. |
|
|
Just to reiterate, cool idea, but not a clue as to its viability. |
|
|
A priori, I think it's about as feasible as the original
GloFish, i.e. I can't see any reason why it couldn't be
feased. |
|
|
So to make this (skeletal) muscle specific; there
are a bunch of myosin proteins that are found only
in this cell type. Simply bunging one of those
promoters on the front end of the DNA used in a
Cre recombination system should get you to where
you need to be, I'd recomend the promoter for
myosin light chain. There are a whole bunch of
targetting sequences for the cytosol, but you'd
suck it and see before you added one of those.
I'm not really a muscle expert but I think the actual
creation of this zebra fish, is trivial to someone
who's a got a bit of a Zebra Fish bent. And it will
work. |
|
|
EDIT, the amplitude of calcium signals is pretty
huge, and the Kd of most of the pericams is such
that in muscle at least, it might spend the vast
majority of it's time being fluorescent. However,
there are lower affinity pericam mutants (D2D3 for
example) that might suit better. |
|
|
a quick google suggests that the adult Zebra fish's
heart rate is 125/min. Perfect for a cardiac muscle-
targeted pericam, flashing away in a predominantly
transparent fish. |
|
|
So we finally crack the DNA code..and what do we do, we make fish that glow. Sighs. |
|
|
Anyway, wouldn't it be more fun to make fishermen that could glow in the dark and lure in prey,for example, tax inspectors or something like that.. |
|
|
Holy crap, a genetic modification idea by somebody
who actually appears to have some idea of what he's
talking about! |
|
|
Definite [+] for the mental imagery, although I do
wish that GloFish were legal in my state... |
|
|
Yeah, they're illegal in California. It's truly strange, it's
not like they'd survive in the wild. It's not like GFP is
toxic in any way. Truly, lawmaking based upon
paranoia. |
|
|
Could you make just the fish's eyes flourescent? This might look good in the dark. |
|
|
Forgive me if I'm wrong, but in the case of animals genetically modified into glowing in the dark, wasn't the original gene taken from fluorescent fish in the first place? |
|
|
No.Originally, GFP was isolated from Aquoria Victoria, a
jellyfish. However, it wasn't very good for scientific
use.
It didn't like 37C, it was a bit too happy absorbing UV
light.
Which is where Roger Tsien's '95 Nature paper comes in.
eGFP was stable, convenient, brighter, fast folding, all
round great. Then, someone put a calcium binding
motif
on it, and it can be made so that the protein either folds
into or out of the fluorescent conformation. So, upon
calcium binding it either gets a hell of a lot brighter
(pericam) or a hell of a lot dimmer (inverse pericam). |
|
|
Glofish already have fluorescent eyes. The green glofish
(completely anecdotal) appear to be
blind when the UV light is on and they are very brightly
fluorescent. I can tell because they follow their eyes
straight to the food when the normal light is on. If you
add the UV they swim around apparently attracted to
the scent... following the currents from the filter/pump
setup. |
|
|
I suspect that it is because the GFP is expressed in the
retina. This would somewhat impede useful vision. |
|
| |