Bolige Aoen, Hagiwara Shin-Ya, Zhang Yulan, Goto Ken
Laboratory of Biological Rhythms, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, 080-8555 Japan.
Plant Cell Physiol. 2005 Jun;46(6):931-6. doi: 10.1093/pcp/pci100. Epub 2005 Apr 8.
Cell population growth is gated to occur in particular circadian phases, which has been known for over four decades in various organisms including cyanobacteria and human. However, little is known as to which cell cycle phases from G1 to M are primarily regulated by the circadian rhythm or when in a circadian cycle this primary regulation takes place. We report here that in the flagellate alga Euglena gracilis grown photoautotrophically, the circadian rhythm primarily prevented developmentally matured G2 cells from progressing to mitosis, such that cell population growth occurred only during subjective night. In addition, we found that the circadian rhythm also arrests G1-to-S and S-to-G2 transitions at particular circadian phases.
细胞群体生长被限制在特定的昼夜节律阶段发生，这在包括蓝细菌和人类在内的各种生物体中已为人所知达四十多年。然而，对于从G1到M的哪些细胞周期阶段主要受昼夜节律调节，或者在昼夜节律周期的何时发生这种主要调节，人们所知甚少。我们在此报告，在光自养生长的鞭毛藻纤细裸藻中，昼夜节律主要阻止发育成熟的G2细胞进入有丝分裂，从而使细胞群体生长仅在主观夜间发生。此外，我们发现昼夜节律还在特定的昼夜节律阶段阻止G1到S以及S到G2的转变。
