Synchronization of a Proliferative Population in a Cultured Plant Tissue

The use of synchronized populations of proliferative cells has been. advantageous for the investigation of events of the cell cycle (4, 5, 15) . Most investigations, however, have been carried out with procaryotic and eucaryotic single cells because dependable techniques for synchronization of cells in tissues were virtually unknown . It is therefore desirable, if not necessary, to develop procedures at the tissue level if the mitotic cycle is to be analyzed under conditions where metaphytic as well as metazoic cells are constrained anatomically and undergo normal differentiation . The present note describes the methodology and the cell population kinetics of synchronized cells in the meristem of cultured isolated pea roots . The methodology takes advantage of the fact that the asynchronously dividing cells segregate exclusively into the GI and G2 stages of the mitotic cycle when cultured aseptically in White's medium (14), devoid of carbohydrate (10, 11, 12) . By sequential provision and deprivation of sucrose in conjunction with 5-fluoro-deoxyuridine (FUdR, Hoffmann-LaRoche, Inc., Nutley, N. J .), an inhibitor of DNA synthesis, the meristematic cells can be accumulated in G1 and their distribution at the G I /S boundary can be experimentally regulated .