Target of rapamycin complex 1 and Tap42-associated phosphatases are required for sensing changes in nitrogen conditions in the yeast Saccharomyces cerevisiae
Target of rapamycin complex 1 and Tap42-associated phosphatases are required for sensing changes in nitrogen conditions in the yeast Saccharomyces cerevisiae
复制标题
检测酿酒酵母中氮条件的变化需要雷帕霉素复合物 1 和 Tap42 相关磷酸酶的靶标
DOI：
10.1111/mmi.13858
复制
发表时间：
2017-12-01
影响因子：
3.6
通讯作者：
Jiang, Yu
中科院分区：
文献类型：
--
作者：
Li, Jinmei;Yan, Gonghong;Jiang, Yu
在酵母中，雷帕霉素靶标复合物 1 (TORC1) 和 Tap42 相关磷酸酶调节参与氮限制反应和氮辨别途径的基因表达。然而，目前尚不清楚 TORC1 和磷酸酶是否是感知氮条件所必需的。利用tor2和tap42的温度敏感突变体，我们研究了TORC1和Tap42在Gln3进入核中的作用，Gln3是酵母氮代谢中的关键转录因子，响应氮条件的变化。我们的数据表明，TORC1 对于氮限制和氮质量下降时 Gln3 进入核至关重要。然而，只有在氮限制条件下才需要 Tap42 相关磷酸酶。在贫氮培养基中生长的细胞中，氮渗透酶重激活激酶 (Npr1) 抑制 TORC1 活性并改变其与 Tap42 的关联，使 Tap42 相关磷酸酶对氮限制无反应。这些发现证明了 TORC1 和 Tap42 相关磷酸酶在感知氮条件中的直接作用，并揭示了一种 Npr1 依赖性机制，该机制控制 TORC1 和磷酸酶以响应氮质量的变化。
In yeast target of rapamycin complex 1 (TORC1) and Tap42-associated phosphatases regulate expression of genes involved in nitrogen limitation response and the nitrogen discrimination pathway. However, it remains unclear whether TORC1 and the phosphatases are required for sensing nitrogen conditions. Utilizing temperature sensitive mutants of tor2 and tap42, we examined the role of TORC1 and Tap42 in nuclear entry of Gln3, a key transcription factor in yeast nitrogen metabolism, in response to changes in nitrogen conditions. Our data show that TORC1 is essential for Gln3 nuclear entry upon nitrogen limitation and downshift in nitrogen quality. However, Tap42-associated phosphatases are required only under nitrogen limitation condition. In cells grown in poor nitrogen medium, the nitrogen permease reactivator kinase (Npr1) inhibits TORC1 activity andalters its association with Tap42, rendering Tap42-associated phosphatases unresponsive to nitrogen limitation. These findings demonstrate a direct role for TORC1 and Tap42-associated phosphatases in sensing nitrogen conditions and unveil an Npr1-dependent mechanism that controls TORC1 and the phosphatases in response to changes in nitrogen quality.