The Pattern of Protein Accumulation in Relation to DNA Replication in Jerusalem Artichoke Callus Cultures

While the synchronous first division cycle in cultured explantsfrom Jerusalem artichoke tubers may vary in duration from oneto two days the length of the ‘S’ phase of thiscycle remains approximately constant at 14 h. A study of thepattern of protein accumulation in relation to this ‘S’phase shows the development of three different populations ofcells in an initially uniform explant. Cells from the centreof the explant accumulate neither DNA or protein while cellsin the peripheral layers accumulate protein according to thesame pattern irrespective of whether they synthesize DNA ornot. This similarity between dividing and nondividing cellsis of interest in considering cellular events leading to celldivision.