A sophisticated two-component signaling system regulates the meiotic cell differentiation in response to oxidative stress in S.pombe.

粟酒裂殖酵母的性别分化似乎是由环境胁迫（如氮饥饿）诱导的。ste 11基因的表达在性分化过程中起着重要作用，其信息素介导的信号通路的分子机制已有相当多的研究。然而，很少有人知道环境信号如何被感知并传递到下游元件以执行性别分化。针对这一特殊问题，我们提供了证据证明，一个双组分信号转导系统在其中起着至关重要的作用，其中三个组氨酸激酶（Phk 1/2/3），一个Hpt因子（Spy 1）和两个反应调节因子（Mcs 4和Ptt 1）与下游的Sty 1 MAPK级联反应协同作用。这种复杂的信号传导机制被证明参与诱导减数分裂响应氧化应激，通过直接触发诱导基因的表达，如ate 11，mam 2和mei 2，这是在减数分裂的初始阶段所需的。这是第一个迹象表明，细菌类型的His-Asp磷酸化信号传导与真核细胞周期控制的基本过程密切相关。我们还表明，在裂殖酵母，粟酒裂殖酵母中的细胞分裂素响应传感器的功能，AHK 4 His激酶。

The sexual differentiation of S.pombe appears to be induced by environmental stress, such as nitrogen starvation. The expression of ste11 is crucial for sexual differentiation, and its molecular mechanisms of pheromon-mediated signal pathway have fairly well-documented. However, litlle is known about how the environmental signal(s) is perceived and relayed to the downstream elements to execute the sexual differentiation. With regard to this particular issue, here we provide evidens that a two-component signal transduction system pay a crucial role, in whichthree histidine-kinases(Phk1/2/3), one Hpt factor (Spy1) and two response-regulators(Mcs4 and Ptt1) act in concert with the downstream Sty1 MAPK cascade. This sophisticated signaling mechanism was demonstrated to be involved in the induction of meiosis in response to oxidative stress, through directly triggering the induction of expression of gene such as ate11, mam2, and mei2, which are required in the initial stage of meiosis. This is the first indication that a bacterial type of His-Asp phosphorelay signaling is closely linked to the fundamental process og eukaryotic cell cycle control. We also showed that the Arabidopis AHK4 His kinase functions as a cytokinin responsive sensor in the fission yeast, S.pombe.