Carolyn J Mattingly asks: Can anyone advise me as to the best way to visualize the expression of gfp in embryos? as well as adult fish? Of course it depends on the plasmid used, the concentration of DNA injected etc, but can someone give me an idea of how long it takes for the gfp to begin being expressed and how long that expression seems to last? Thanks so much for any help you can offer.
Using a ubiquitously-expressed promoter, you should start getting embryonic expression soon after transcription starts at the midblastula transition (ie, about 50% epiboly). Whether you get expression in the adult of course depends on the promoter and presumably requires stable integration of the plasmid.
As far as microscopy, you need to use the right filter set. For wildtype GFP, a Hoechst or DAPI cube (UV excitation) should work fine, as long as the emission filter is a longpass and not a bandpass. For red-shifted excitation mutants, a fluorescein cube (blue excitation) should work fine.
Hope this helps. Good luck,
Chi-Bin Chien
< MPI fuer Entwicklungsbiologie | phone: 49-7071-601 335 >
< Spemannstrasse 35/Abt. I | fax: 49-7071-601 305 >
< 72076 Tuebingen, Germany | chien@mpib-tuebingen.mpg.de >