High resolution mapping of in situ hybridized biotinylated DNA to surface-spread Drosophila polytene chromosomes.
We describe a method of mapping genes or transcripts on polytene chromosomes by transmission electron microscopy. We present several applications which illustrate that, in favorable cases, the method has a resolution of ca. 10 kg, and that high resolution mapping of hybridization sites relative to bands and puffs can be achieved. We mapped sites of transcription for poly-(A) RNA and present evidence which shows that these sites are localized in some bands and puffs, but are also found in interbands.
D000818:Animals; D001345:Autoradiography; D001710:Biotin; D002874:Chromosome Mapping; D004247:DNA / Q000235:genetics*; D004262:DNA Restriction Enzymes; D004331:Drosophila melanogaster / Q000235:genetics*; D008854:Microscopy, Electron; D009693:Nucleic Acid Hybridization; D014316:Tritium
D014316:Tritium; D001710:Biotin; D004247:DNA; D004262:DNA Restriction Enzymes