小柯机器人

美国马萨诸塞州综合医院Jen Sheen、Ruiqiang Ye等研究人员合作发现，葡萄糖驱动的TOR-FIE-PRC2信号控制植物发育。该项研究成果于2022年9月14日在线发表在《自然》杂志上。

研究人员表明葡萄糖激活的雷帕霉素靶标（TOR）激酶控制拟南芥全基因组的组蛋白H3在K27处的三甲基化（H3K27me3），这种修饰调节细胞命运和发育。研究人员确定FERTILIZATION-INDEPENDOSPERM（FIE）是Polycomb repressive complex 2（PRC2）不可缺少的成分，它能催化H3K27me3，是TOR的一个靶标。TOR的直接磷酸化促进了FIE从细胞质到细胞核的动态易位。FIE上的磷酸化位点的突变废除了全局的H3K27me3景观，重新规划了转录组并破坏了植物的器官发生。此外，葡萄糖-TOR-FIE-PRC2信号调节了春化诱导的花期转变。

研究人员提出，这个信号轴作为一个营养检查点，导致关键转录因子基因的表观遗传沉默，这些基因在嫩枝和根分生组织中指定干细胞的命运，并控制叶、花和长角果的形态、分枝和无性繁殖的过渡。这项发现揭示了营养信号在直接表观基因组重编程中的基本机制，对多细胞生物的发育控制具有广泛的意义。

据了解，营养物质和能量已经成为植物和动物发育过程中的核心调节因素。演化保守的TOR激酶是控制生长的营养和能量信号的核心整合因子。尽管它在翻译、增殖、代谢和自噬中起着关键的调节作用，但对TOR如何影响发育过渡和分化却知之甚少。

附：英文原文

Title: Glucose-driven TOR–FIE–PRC2 signalling controls plant development

Author: Ye, Ruiqiang, Wang, Meiyue, Du, Hao, Chhajed, Shweta, Koh, Jin, Liu, Kun-hsiang, Shin, Jinwoo, Wu, Yue, Shi, Lin, Xu, Lin, Chen, Sixue, Zhang, Yijing, Sheen, Jen

Issue&Volume: 2022-09-14

Abstract: Nutrients and energy have emerged as central modulators of developmental programmes in plants and animals1,2,3. The evolutionarily conserved target of rapamycin (TOR) kinase is a master integrator of nutrient and energy signalling that controls growth. Despite its key regulatory roles in translation, proliferation, metabolism and autophagy2,3,4,5, little is known about how TOR shapes developmental transitions and differentiation. Here we show that glucose-activated TOR kinase controls genome-wide histone H3 trimethylation at K27 (H3K27me3) in Arabidopsis thaliana, which regulates cell fate and development6,7,8,9,10. We identify FERTILIZATION-INDEPENDENT ENDOSPERM (FIE), an indispensable component of Polycomb repressive complex 2 (PRC2), which catalyses H3K27me3 (refs. 6,7,8,10,11,12), as a TOR target. Direct phosphorylation by TOR promotes the dynamic translocation of FIE from the cytoplasm to the nucleus. Mutation of the phosphorylation site on FIE abrogates the global H3K27me3 landscape, reprogrammes the transcriptome and disrupts organogenesis in plants. Moreover, glucose–TOR–FIE–PRC2 signalling modulates vernalization-induced floral transition. We propose that this signalling axis serves as a nutritional checkpoint leading to epigenetic silencing of key transcription factor genes that specify stem cell destiny in shoot and root meristems and control leaf, flower and silique patterning, branching and vegetative-to-reproduction transition. Our findings reveal a fundamental mechanism of nutrient signalling in direct epigenome reprogramming, with broad relevance for the developmental control of multicellular organisms.

DOI: 10.1038/s41586-022-05171-5

Source: https://www.nature.com/articles/s41586-022-05171-5

Nature：《自然》，创刊于1869年。隶属于施普林格·自然出版集团，最新IF：69.504
官方网址：http://www.nature.com/
投稿链接：http://www.nature.com/authors/submit_manuscript.html