abnormal regulation of mitotic cell cycle abnormal mitotic cell cycle regulation upon nitrogen source shift 2016-01-19T13:39:34Z abnormal mitotic cell cycle regulation upon nitrogen source shift during vegetative growth abnormal cell cycle regulation upon nitrogen source shift during mitotic cell cycle FYPO:0005206 A cellular response phenotype observed in the vegetative growth phase of the life cycle in which the regulation of the mitotic cell cycle when cells are shifted from one nitrogen source to another. Normally, cell division is delayed upon shifting from a poor to a rich nitrogen source, and accelerated upon shifting from a rich to a poor nitrogen source. midori abnormal mitotic cell cycle regulation during cellular response to nitrogen source shift abnormal cell cycle regulation upon nitrogen source shift Good (or rich) nitrogen sources are distinguished from poor sources based on how readily nitrogen is assimilated into cellular metabolism. In microorganisms, good nitrogen sources generally support higher cell population growth rates than poor sources. In fission yeast, cells divide at a smaller size when grown on a poor nitrogen source than in nitrogen-rich media; proline is commonly used as a poor nitrogen source.