Energy Requirements of Mitosis

As already mentioned the most important raw material for the support of mitosis in mammalian tissues appears to be glucose, and there is evidence from observations like those of Brown and Rickless (1949) that sucrose may be equally essential to mitosis in plants. Because of this, and because the actions of all those hormones now known to influence mitosis can be wholly or partly explained in terms of their effects on carbohydrate metabolism, it is appropriate to consider briefly what is now known of the energy requirements of cell division. 

These results are in general agreement with the limited number of observations on plant tissues. The work of Erickson (1947) on Lilium 

These results are in agreement with the suggestion that tissues vary widely in their ability to absorb that glucose which is abundant in the blood and in the intercellular spaces. Thus in the favorable conditions of tissue culture the rate of glucose uptake by mammalian epidermis is normally low, whereas in the unfavorable conditions of starvation the rate of glucose uptake by embryonic tissues, tumors, and certain adult tissues such as lymph node centers is normally high. 

A number of indications caused attention to be directed to the first step, the phosphorylation of glucose. Preliminary attempts to discover whether this is in fact a slow reaction involved the use as substrate of glucose-6-phosphate, glucose-l-phosphate, or fructose-1,6-diphosphate. The attempts failed because none of these phosphorylated intermediates proved capable of supporting any mitosis at all, and the conclusion was 

Strong evidence, which has been previously reviewed in detail (Bullough, 1952a), exists to indicate that the most important single 

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