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PubMed · 6836293

Electron microscope tomography: transcription in three dimensions.

D E Olins·A L Olins·H A Levy·R C Durfee·S M Margle·E P Tinnel·S D Dover
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Abstract

Three-dimensional reconstruction of an asymmetric biological ultrastructure has been achieved by tomographic analysis of electron micrographs of sections tilted on a goniometer specimen stage. Aligned micrographs could be displayed as red-green three-dimensional movies. The techniques have been applied to portions of in situ transcription units of a Balbiani ring in the polytene chromosomes of the midge Chironomus tentans. Current data suggest a DNA compaction of about 8 to 1 in a transcription unit. Nascent ribonucleoprotein granules display an imperfect sixfold helical arrangement around the chromatin axis.

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AnimalsChironomidaeChromatinDNAMicroscopy, ElectronRibonucleoproteinsTomographyTranscription, GeneticJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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D E Olins, A L Olins, H A Levy, R C Durfee, S M Margle, E P Tinnel, S D Dover. 1983-04-29. Electron microscope tomography: transcription in three dimensions.. https://doi.org/10.1126/science.6836293

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