Does the interchromatin compartment contain actin?

K S Crowley; K Brasch

doi:10.1016/0309-1651(87)90016-6

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Does the interchromatin compartment contain actin?

K S Crowley·K Brasch

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Abstract

Transient blockage of transcription in chick liver by alpha-amanitin results in a temporary clearing of nucleoplasmic regions in affected nuclei and concurrent exposure in situ of a discrete interchromatin framework. This is accompanied by sharp decreases in total nuclear RNA (approximately 28%) and nonhistone protein content (approximately 18%). Electrophoretic analysis of matrix fraction proteins from such highly denuded nuclei shows a marked relative enrichment in actin and RNP-derived polypeptides. These observations suggest that actin is a real constituent of the interchromatin region and supports various reports that this protein may have a basic structural role in nuclei.

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Actins Amanitins Animals Cell Nucleus Chickens Chromatin Chromosomal Proteins, Non-Histone Electrophoresis Liver Microscopy, Electron RNA Ribonucleoproteins Transcription, Genetic Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.

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K S Crowley, K Brasch. 1987. Does the interchromatin compartment contain actin?. https://doi.org/10.1016/0309-1651(87)90016-6

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