Research Department of Genetics, Evolution &Environment and UCL Institute of Healthy Ageing, University College London, Gower Street, WC1E 6BT, London, UK.
Sci Rep. 2017 Mar 10;7:44257. doi: 10.1038/srep44257.
The Target of Rapamycin (TOR) signalling network plays important roles in aging and disease. The AMP-activated protein kinase (AMPK) and the Gsk3 kinase inhibit TOR during stress. We performed genetic interaction screens using synthetic genetic arrays (SGA) with gsk3 and amk2 as query mutants, the latter encoding the regulatory subunit of AMPK. We identified 69 negative and 82 positive common genetic interactors, with functions related to cellular growth and stress. The 120 gsk3-specific negative interactors included genes functioning in translation and ribosomes. The 215 amk2-specific negative interactors included genes functioning in chromatin silencing and DNA damage repair. Both amk2- and gsk3-specific interactors were enriched in phenotype categories related to abnormal cell size and shape. We also performed SGA screen with the amk2 gsk3 double mutant as a query. Mutants sensitive to 5-fluorouracil, an anticancer drug are under-represented within the 305 positive interactors specific for the amk2 gsk3 query. The triple-mutant SGA screen showed higher number of negative interactions than the double mutant SGA screens and uncovered additional genetic network information. These results reveal common and specialized roles of AMPK and Gsk3 in mediating TOR-dependent processes, indicating that AMPK and Gsk3 act in parallel to inhibit TOR function in fission yeast.
雷帕霉素靶蛋白（TOR）信号网络在衰老和疾病中发挥着重要作用。在应激条件下，AMP 激活的蛋白激酶（AMPK）和 Gsk3 激酶会抑制 TOR。我们使用合成遗传图谱（SGA）进行了遗传相互作用筛选，以 gsk3 和 amk2 作为查询突变体，后者编码 AMPK 的调节亚基。我们鉴定了 69 个负向和 82 个正向共同遗传相互作用因子，它们的功能与细胞生长和应激有关。120 个 gsk3 特异性负相互作用因子包括参与翻译和核糖体的基因。215 个 amk2 特异性负相互作用因子包括参与染色质沉默和 DNA 损伤修复的基因。amk2 和 gsk3 特异性相互作用因子都富集在与细胞大小和形状异常相关的表型类别中。我们还使用 amk2 gsk3 双突变体作为查询进行了 SGA 筛选。对氟尿嘧啶（一种抗癌药物）敏感的突变体在 amk2 gsk3 查询的 305 个阳性相互作用因子中代表性不足。三重突变体 SGA 筛选显示出比双突变体 SGA 筛选更多的负相互作用，揭示了额外的遗传网络信息。这些结果揭示了 AMPK 和 Gsk3 在介导 TOR 依赖性过程中的共同和特殊作用，表明 AMPK 和 Gsk3 平行作用以抑制裂殖酵母中的 TOR 功能。
