An H3K27me3 demethylase-HSFA2 regulatory loop orchestrates transgenerational thermomemory in Arabidopsis
An H3K27me3 demethylase-HSFA2 regulatory loop orchestrates transgenerational thermomemory in Arabidopsis
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H3K27me3 去甲基化酶-HSFA2 调节环在拟南芥中协调跨代热记忆
DOI：
10.1038/s41422-019-0145-8
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发表时间：
2019-05-01
期刊：
影响因子：
44.1
通讯作者：
He, Zuhua
中科院分区：
文献类型：
--
作者：
Liu, Junzhong;Feng, Lili;He, Zuhua
全球变暖对植物的生长和健康有着深远的影响。植物已经进化出复杂的表观遗传机制来快速响应热，并表现出热诱导的转录后基因沉默（PTGS）释放的跨代记忆。然而，热记忆是如何传递给后代和生理相关性是难以捉摸的。在这里，我们表明，热诱导的热休克转移因子A2（HSFA 2）直接激活H3 K27 me 3脱甲基酶相对于早期开花6（参考文献6），这反过来又去抑制HSFA 2。REF 6和HSFA 2建立了一个可遗传的反馈环，并激活E3泛素连接酶，基因沉默3（SGS 3）-相互作用蛋白1（SGIP 1）的支持者。SGIP 1介导的SGS 3降解导致反式作用siRNA（tasiRNA）的生物合成受到抑制。REF 6-HSFA 2环和还原型tasiRNA会聚以释放热诱导的TAS 1靶标5（HTT 5），其驱动早期开花但减弱免疫力。因此，热通过涉及组蛋白脱甲基酶、转录因子和tasiRNA的协调表观遗传网络诱导传递表型，确保生殖成功和跨代应激适应。
Global warming has profound effects on plant growth and fitness. Plants have evolved sophisticated epigenetic machinery to respond quickly to heat, and exhibit transgenerational memory of the heat-induced release of post-transcriptional gene silencing (PTGS). However, how thermomemory is transmitted to progeny and the physiological relevance are elusive. Here we show that heat-induced HEAT SHOCK TRANSCRIPTION FACTOR A2 (HSFA2) directly activates the H3K27me3 demethylase RELATIVE OF EARLY FLOWERING 6 (REF6), which in turn derepresses HSFA2. REF6 and HSFA2 establish a heritable feedback loop, and activate an E3 ubiquitin ligase, SUPPRESSOR OF GENE SILENCING 3 (SGS3)-INTERACTING PROTEIN 1 (SGIP1). SGIP1-mediated SGS3 degradation leads to inhibited biosynthesis of trans-acting siRNA (tasiRNA). The REF6-HSFA2 loop and reduced tasiRNA converge to release HEAT-INDUCED TAS1 TARGET 5 (HTT5), which drives early flowering but attenuates immunity. Thus, heat induces transmitted phenotypes via a coordinated epigenetic network involving histone demethylases, transcription factors, and tasiRNAs, ensuring reproductive success and transgenerational stress adaptation.