ESTRADIOL, A NEW HAPTEN FOR DETECTING NUCLEIC-ACID SEQUENCES BY FISH

Oestradiol has been conjugated to allylamine-dUTP with an 11-atom spac er to allow enzymatic incorporation of the label into DNA sequences. I n a comparative DNA and mRNA FISH study we have used DNA probes that w ere either labelled with digoxigenin, biotin or oestradiol. Results sh ow that oestradiol-labelled probes can detect DNA and RNA sequences in FISH equally well as digoxigenin-and biotin-labelled probes. Further, no crossreactivity between the various hapten-specific antibodies and the three haptens were observed. Binding of the rabbit anti-oestradio l antibody to endogenous oestrogen in various tissues was not observed under the conditions tested. In view of the increasing demands for mu lti-colour DNA and mRNA FISH applications, oestradiol is a welcome add ition to the collection of haptens employed in FISH.