Fission yeast autophagy induced by nitrogen starvation generates a nitrogen source that drives adaptation processes
Fission yeast autophagy induced by nitrogen starvation generates a nitrogen source that drives adaptation processes
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DOI：
10.1111/j.1365-2443.2007.01041.x
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发表时间：
2007-02-01
期刊：
影响因子：
2.1
通讯作者：
Yamamoto, Masayuki
中科院分区：
文献类型：
--
作者：
Kohda, Toshiki A.;Tanaka, Kayoko;Yamamoto, Masayuki
自噬是一种保守的大宗蛋白质降解过程，被认为在生物体被迫从根本上改变其命运时发挥作用，包括营养饥饿、分化和发育。在我们目前的研究中，我们已经确定分裂酵母自噬是一种由环境氮剥夺引起的大量蛋白质降解过程，其影响被认为是一种适应性反应，触发了性别分化。自噬缺陷突变体在没有氮源的情况下是不育的，但在供氮的情况下可以完成性别分化，这表明自噬的主要功能是提供氮源。此外，环境中的氮素水平起着自噬“开/关”开关的作用，而性别分化所必需的成分对于这一调节是必不可少的。我们认为，裂解酵母的自噬功能是提供氮，并在细胞无法获得外源氮时被激活，从而确保它们能够适应并随后繁殖。
Autophagy is a conserved bulk protein degradation process that is proposed to play a role in events that arise when organisms are forced to radically change their fate, including nutritional starvation, differentiation and development. In our present study, we have identified fission yeast autophagy as a bulk protein degradation process induced by the deprivation of environmental nitrogen, the effects of which are known to trigger sexual differentiation as an adaptive response. Autophagy-defective mutants were found to be sterile in the absence of environmental nitrogen, but could complete sexual differentiation when nitrogen was supplied, suggesting that the major function of autophagy is to provide a nitrogen source. In addition, the environmental nitrogen levels act as an autophagy "on/off" switch, whereas components essential for sexual differentiation were dispensable for this regulation. We propose that fission yeast autophagy functions to supply nitrogen and is activated when cells cannot access exogenous nitrogen, thus ensuring that they can adapt and subsequently propagate.