Strand‐specific transcription of the simple sequences poly[(dG‐dT):(dC‐dA)] and poly[(dG‐dA):(dC‐dT)] in D. melanogaster embryos revealed by S1 nuclease treatment

The transcription of different strands of the simple sequences poly[(dG‐dT):(dC‐dA)] and poly[(dG‐dA):(dT‐dC)] in Drosophila melanogaster embryos was studied. After selective labelling of one strand, the polymers were hybridized with immobilized RNA and hybrids were treated on filters with S1 nuclease. Appropriate control has shown that this treatment destroys sandwich‐like complexes and leaves only true hybrids. Transcription of poly[(dG‐dA):(dT‐dC)] proved to be nearly symmetric, while poly(dG‐dT) is transcribed 3‐times more intensively than poly(dA‐dC). Our approach allowed us to estimate the relative content of simple sequences in RNA.