Fam96 recruits creatine kinase to fuel spindle formation during cell mitosis

【作者】 陈祥军； 闫永彬；

【机构】 清华大学生命科学院；

【摘要】 Cell cycle progression requires high energy fluxes to successfully divide the mother cellsinto two daughter cells. However, the energy homeostasis during cell cycle progression remainsto be elucidated.Creatine kinase(CK) plays a key role in maintaining cellular energy homeostasis. In this research,we studied the potential roles of CK in mitosis. By yeast two-hybrid using CK as thebiat, we identified Fam96 as a potential binding partner of CK. We further verified CKFam96 interaction by Co-IP and GST-pulldown experiments. The interaction betweenFam96 and CK was unaffected by the CK substrate ATP, ADP, phosphocreatine or creatine.Domain-mapping indicated that the region between residue 42 and 121 is the key part ofFam96 to interact with CK. In the cells, Fam96 co-localized with CK, and the major locationswas the mitosis spindle during metaphase. The knockdown of either proteins exhibitedsimilar phenotypes with abnormal mitosis spindle and arrest in the cell cycle progression.By immunoprecipitation, we showed that both proteins existed in a large complex. Fam96 acted as a scaffold protein to recruit the other members to the spindle. Our results suggestedthat CK might fuel the spindle formation and thus maintain the local ATP levels aroundspindle, which facilitate to the spindle formation and cell division. Our results also suggestedthat energy homeostasis in micro cellular domains plays a crucial role in the growth,survival and proliferation of the cells.更多还原

【Abstract】 Cell cycle progression requires high energy fluxes to successfully divide the mother cellsinto two daughter cells. However, the energy homeostasis during cell cycle progression remainsto be elucidated.Creatine kinase(CK) plays a key role in maintaining cellular energy homeostasis. In this research,we studied the potential roles of CK in mitosis. By yeast two-hybrid using CK as thebiat, we identified Fam96 as a potential binding partner of CK. We further verified CKFam96 interaction by Co-IP and GST-pulldown experiments. The interaction betweenFam96 and CK was unaffected by the CK substrate ATP, ADP, phosphocreatine or creatine.Domain-mapping indicated that the region between residue 42 and 121 is the key part ofFam96 to interact with CK. In the cells, Fam96 co-localized with CK, and the major locationswas the mitosis spindle during metaphase. The knockdown of either proteins exhibitedsimilar phenotypes with abnormal mitosis spindle and arrest in the cell cycle progression.By immunoprecipitation, we showed that both proteins existed in a large complex. Fam96 acted as a scaffold protein to recruit the other members to the spindle. Our results suggestedthat CK might fuel the spindle formation and thus maintain the local ATP levels aroundspindle, which facilitate to the spindle formation and cell division. Our results also suggestedthat energy homeostasis in micro cellular domains plays a crucial role in the growth,survival and proliferation of the cells.更多还原