GFP and black light eye sensitivty

I have a GFP gene leucistic axolotl and it didn't take me long to realize that the little axolotl really hates being exposed to black light. Since UV light is not all that harsh and probably not in the axolotl range of vision I used to assume that the little critter was reacting to the greenish glow that suddenly appeared in the tank. I rarely used the black light on her (just once in a while to show people the gene) and didn't give it much thought.

However looking at a recent close up pic I took of my axolotl in normal light I've had a new theory.

When you look at the pupils of the GFP axolotl you can see the tell tale green cast since the gene codes for a slightly green color even in normal light. When you can see a color in a pupil you're actually seeing a color in the retina (since the pupil is just a hole). Like when you see a red pupil in an albino you're seeing the blood in the back of the retina, in most animals pupils appear black due the fact that the retinal and iris tissue has pigments that absorb the light before it can escape again where as there is more light bouncing back out of an albino eye .

So if the GFP gene is present in the retina cells that means when the poor little axolotl is being exposed to a black light the back of the animals retinas are probably glowing as well. It would be a serious sensory overload to suddenly have the back of your eye glow!

Do others out there with leucistic or albino GFP axolotl find that their animals react negatively (racing around the tank, trying to hide, thrashing) when exposed to black light? If yours does not, does yours show green in the pupils under normal light?

Photos taken under normal light showing bright green pupils of the GFP gene in my axolotl.

I think your theory makes a lot of sense.

It's amazing to see the green pupils under normal light.

I hope that your findings are read & understood by those who want to subject their GFP's to constant black light UV.



<3 >o_o< <3

I think constant exposure to black light should be looked into further before being tried on fish as well. The eyes on the new tiger barb and tetra glowfish are green as well.

Lots of GFP threads lately..

But your theory makes perfect sense. I had assumed it would disturb them because of something like that.. Plus I feel like the peripheral of the sudden glow would agitate them

I was in high school when scientists first developed the GFP gene in danio and people worldwide were in an UPROAR over genetic modification. I thought it was *awesome* and I was hoping that someday it would be something that the public could get their hands on. Now they are in petsmarts. So when I learned that someone had put the GFP in axolotl I was so excited.

However now that I'm seeing the effects of the gene for myself (this is the first 'glo gene' animal I've owned, despite my initial excitement I did not run out and get the fish when they became available) I'm a little more hesitant on the idea.

I know why they did in the first place. A gene that said "Hey! Look! You did it! I'm right here and you can see that I glow!" is a great gene to prove that you spliced it into another animal's code. However, maybe then taking that gene and putting it into pets...

Well, who am I to talk? I *have* one! And I do love her! Would I have gotten an axolotl if they didn't have the glow gene? Maybe not. It was a serious draw for me to not only have a very awesome creature, but a very awesome creature that was genetically modified.

However, now that I see that modification may have ill effects on the animal I have some guilt.

I will continue to love my Bluebell! But I will *not* be buying a "GloFish Aquarium" anytime soon.

i just recently found this article and thought this would be good info to add to this thread, especially for future searches

Characterization of an ultraviolet photoreception mechanism in the retina of an amphibian, the axolotl (Ambystoma mexicanum). - ResearchGate)

I´ve been arguing this very same thing for quite some time. Axolotls come from a deep lake with lots of sediment, they are sensitive to light and tend to avoid it. Exposing a GFP axolotl to a wavelength that makes its eyes glow from the inside is exposing it to light they can´t possibly scape and the stressful effects of this can be readily observed.
That doesn´t even take into account the possible negative effects of exposing an animal that is not adapted to withstand exposure to UV light to it, which is even worse with albino and leucistics which have no protection whatsoever.

I think it's also worth remembering that it's not just black light that will make the critter's eye fluoresce. Normal daylight will do it too. If you have a "neon" coloured object and it appears to look bright and neony, it means there's UV light there, even if there's normal light as well. If you can't see a neon coloured object looking bright, then there's no UV around, and only then will the axolotl's eye be safe from having its internal glow on.

The green in my Axolotls eyes is always visible as well. But under a backlight they glow bright. When I first put a light on him, he swam straight towards the light and was "biting" the surface of the water. I took that as a sign of stress and removed the light. I don't use it. I guess my GD's has a fight over flight stress response, haha,