>Hi Folks,
>
>      A colleague wants to stain DNA and view it on
>a visible-wavelength confocal.  However, she wants
>a stain that stains only DNA, not RNA and believes
>that all of the visible-wavelength probes that stain
>DNA also stain RNA.  [based largely on what's in
>the Molecular Probes catalog].
>      Does anyone know of a visible stain that stains
>DNA either exclusively, or at least more brightly then
>RNA?
>
>   Thanks for any suggestions,
>Don

the simple trick is to stain with propidium ioidide and add RNAse to remove
the RNA staining - this works nicely!

Propidium iodide stasining
For sections: add 100ug/ml RNAse, 10 m at R.T.
For wholemount: add the RNAse in 1% triton (and hope that you are not doing
anything needing lipid stability) for about 30 m
Add 1:104  PrI (sat) for 30m (section) or an hour or two for wholemeount

(In fact, we add the RNAse and PrI together!)


Jonathan Bard


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                                 Jonathan Bard

                Department of Biomedical Sciences,

              Hugh Robson Building, George Square

        Edinburgh University, Edinburgh EH8 9XD, UK

Telephone (44) (0)131.650.3107    Fax: (44) (0)131.650.6545

     website: http://www.bms.ed.ac.uk/staff/bard/index.htm

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