Electrokinetic properties of nuclear surfaces A comparison of nuclei from normal and regenerating rat liver

Abstract

1. 1. Studies of various isolation procedures for nuclei were found to yield nuclear surfaces with significantly different electrokinetic properties. Citric acid-extracted nuclei have surface properties similar to those of the intact liver cell; citric acid-sucrose-extracted nuclei also have similar characteristics although these may be masked by variable irreversible DNA adsorption especially when using low ionic strength media for their isolation or electrophoretic examination. Sucrose extracted nuclei displayed considerable electrokinetic instability consistent with the gradual desorption of surface cytoplasmic components. 2. 2. A comparison of nuclei from normal and regenerating liver revealed no difference in their surface electrokinetic properties despite the probable adsorption of DNA at the nuclear surface in both groups when citric acid-sucrose-isolated nuclei were examined. 3. 3. In no instance was sialic acid demonstrable on the nuclear surface.