A series of three calli were obtained from the same sugarbeet strain: a normal (N) auxin- and cytokinin- dependent one, a fully habituated auxin- and cytokinin- independent shoot- producing one (HO for habituated organogenic) and a fully habituated non-organogenic one (HNO) made of true cancerous cells. These calli constitute a unique neoplastic progression. Original and previous results dealing with the hormonal status and metabolism of the three calli, including auxins, cytokinins, polyamines and ethylene, have been comparatively and critically examined, the objective being to eventually detect mutations. Rather than abrupt modifications, important metabolic shifts in hormonal status metabolism and sensitivity were observed: for instance while HNO growth reactions to auxins and cytokinins were diminished, sensititvities to polyamines and ethylene were increased. These shifts appear as the result of disturbed general metabolisms (of sugar, of nitrogen). Some key cycles and pathways, for instance the Krebs cycle and the tetrapyrrole biosynthetic pathway are atypical in the HNO cancerous cells. These deregulations appear to be due more to substrate- inducible enzyme adaptation that to true mutations. The other lesson from the present appraisal is that the hormonal metabolisms cannot be dissociated from the general biochemical cycles and pathways, which entertain with them reciprocal relationships.
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