Changes in the activity of alcohol dehydrogenase during the cell cycle of the fission yeast Schizosaccharomyces pombe

• Published in: Journal of cell science Vol. 99; no. 1; pp. 193 - 199
• Main Authors: Vicente-Soler, J, Creanor, J, Bisset, Y, Mitchison, J.M
• Format: Journal Article
• Language: English
• Published: 1991
• Subjects: alcohol dehydrogenase; cell culture; enzyme activity; estrus synchronization; glycolysis; mutants; Saccharomycetales; Schizosaccharomyces pombe
• ISSN: 0021-9533; 1477-9137
• DOI: 10.1242/jcs.99.1.193

ABSTRACT The activity of alcohol dehydrogenase (ADHase) was followed in synchronous cultures of Schizosaccharomyces pombe. In selection synchronised cultures of wild-type cells, it followed a linear pattern in which there was a constant rate of increase of activity followed by a doubling of this rate at the end of the cycle. The same pattern was also found in selection synchronised cells of wee mutants except that the point of rate change was shifted to 0.27 of the cycle. A similar linear pattern was also found in the shortened cell cycles produced by induction synchrony (block and release of the mutant cdc2.33) but the rate change point was at about 0.75 of the cycle. In the mutant cdcl3.117, there was a marked fall in the rate of activity increase at 35°C but not at 37°C. In all these situations, the ADHase activity closely paralleled in pattern and in timing the rate of production of CO2 established in earlier papers. This suggests a coordinate control of the flux through glycolysis and the activity of the last enzyme in the glycolytic pathway in yeast However, an interesting difference indicating a loss of the coordinate control occurred in ‘synchronous’ cultures of cdc2.33 in which small cells had been selected but in which the DNA-division cycle had been blocked by a shift-up to the restrictive temperature. Rate changes both in CO2 production and in ADHase activity continued in these blocked synchronous cultures but the timing was different. With ADHase activity the timing was 15 % greater than that in a normal cell cycle whereas with CO2 production it was 15% less. We suggest that these and other periodic events are subject to independent oscillatory controls in these blocked cultures with timings that differ from each other and from the normal cycle but in the normal cycle the oscillators are all entrained by one or more events of the DNA-division cycle.