PATTERN OF PROTEIN ACCUMULATION IN RELATION TO DNA REPLICATION IN JERUSALEM ARTICHOKE CALLUS CULTURES

While the synchronous first division cycle in cultured explants from Jerusalem artichoke tubers may vary in duration from one to two days the length of the 'S' phase of this cycle remains approximately constant at 14 h. A study of the pattern of protein accumulation in relation to this 'S' phase shows the development of three different populations of cells in an initially uniform explant. Cells from the centre of the explant accumulate neither DNA or protein while cells in the peripheral layers accumulate protein according to the same pattern irrespective of whether they synthesize DNA or not. This similarity between dividing and nondividing cells is of interest in considering cellular events leading to cell division. © 1968 OXFORD UNIVERSITY PRESS.