ABSTRACT
The cavity systems within chicken erythrocyte nuclei and rat liver nuclei were compared using passive probes of radioactive glycogen and active probes of nuclease-armed-glycogen. The passive probe curves have a form that indicates that they are due to passive occupation of spaces and not due to the effects of a limiting membrane.
The technique of probing nuclei with glycogen armed with a small enzyme is described.
The chicken erythrocytes appeared to have 11–15-nm and 4–5-nm cavity systems similar to those we have previously reported in rat nuclei. Evidence is presented to show that the bridge DNA is enclosed within the 4-5-nm cavities in both rat liver and chicken erythrocyte nuclei.
Minor differences between the rat liver and chicken erythrocyte nuclear cavity systems are noted in the region of 5–8 nm. A relatively mild procedure is described for preparing chicken erythrocyte nuclei.
