非典型蛋白激酶RIO广泛分布于三域生物中，真核生物RIO参与核糖体生物合成。最近发现RIO还可能参与DNA代谢、细胞周期调控、细胞代谢与发育等众多过程，且在多种肿瘤细胞中过表达，暗示RIO可以作为潜在的生物标记和抗癌药物的靶标。然而，RIO如何参与众多途径及参与肿瘤发生的机制未知。RIO属于较古老的蛋白激酶，推测具有保守功能，而古菌的Rio蛋白类似于真核生物。本研究以模式嗜热泉古菌冰岛硫化叶菌为材料，利用其完备的遗传操作体系分析两个Rio激酶基因的缺失对核糖体合成、DNA代谢及细胞周期的影响；通过蛋白磷酸化组学分析，寻找可能的靶标蛋白；进一步采用酶活性分析、亲和层析及质谱等方法鉴定Rio靶标蛋白，分析其对不同蛋白底物的磷酸化的生理功能。预期将揭示Rio激酶在古菌中除核糖体合成外的其他功能，有助于了解RIO激酶功能的进化，为揭示真核生物复杂的RIO作用网络及调控机制提供借鉴。

The apytical protein kinase family RIOs is widely distributed in the three domains of life. Eukaryotic RIOs are involved in ribosome biogenesis. Recently, it was shown that RIOs may also play roles in DNA metabolism, cell cycle regulation, cellular metabolism, and development. In addition, RIOs are overexpressed in myriad tumors, suggesting that RIOs are potential biomarkers and targets for anti-cancer drugs. However, how RIOs participate various pathways and tumorigenesis in eukaryotes are still far from clear. RIOs are ancient protein kinases, indicative of conserved functions. In addition, archaeal Rios resemble those in eukaryotes. In this study, using a model crenarchaeon Sulfolobus islandicus, we will systematically characterize the effects of two Rio genes deletion on ribosome biogenesis, DNA metabolism and cell cycle regulation by the well developed genetic system of S. islandicus. The potential substrates of the Rio kinases will be identified based on the phospho-proteomics analysis. Further, enzyme activity analysis, affinity chromatography, and mass spectrometry will be employed to confirm the substrates of the Rio kinases, and to investigate the physiological functions of Rios phosphorylation on their substrates. This will reveal the roles of RIOs in other processes in addition to ribosome biogenesis, which may facilitate the understanding on the evolution of RIO protein kinases and the corresponding researches in eukaryotes.