Changes in the nuclear distribution of cyclin (PCNA) during S-phase are not triggered by post-translational...

Indirect immunofluorescence studies of HeLa cells using PCNA autoantibodies specific for cyclin have revealed striking changes in the nuclear localization of this protein during S-phase. Two-dimensional gel electrophoretic analysis of the [32P]orthophosphate and [35S]methionine labelled proteins from synchronized cells showed that phosphorylation, or other post-translational modifications that are expected to moderately affect the charge of cyclin (acetylation, glycosylation, sialylation, etc.) are not likely part of the mechanism(s) triggering the migration of this protein.