Quenching Fluorescent Proteins

[Confused Dave]

Hello,

I'm looking for a way to reliably inactivate fluorescent proteins
(EGFP and dsRed) without harming epitopes for immuno.

A little background: I'm electroporating inducible constructs into
the chick embryo. We use dsRed as the electroporation control, and
EGFP as a marker for activation of our doxicyclin-inducible construct.
We want to use immunofluorescence to on these samples. We currently
use 4% formalin to fix, washes with PBS+tween, usually ethanol
dehydration for storage, and sucrose-agar embedding for sectioning,
and the fluorescence still comes up strong. Obviously, imaging with
epifluorescence with a green and red channel, we can't add another
fluorophore.

Best case would be a way to specifically kill the RFP leaving the
green intact, although as long as we can recover the GFP with an
antibody, this isn't a problem. Also looking for something that won't
damage our epitopes to badly!

Thanks,
Dave

[Dr Mephesto]

Can you just bleach out the RFP with strong monochromatic light? According to Tsien's paper (http://www.tsienlab.ucsd.edu/Publications/Shaner%202005%20Nature%20Methods%20-%20Choosing%20fluorescent%20proteins.pdf), dsRED have very low photostability.
-Dave