Gregor Mendel Institute of Molecular Plant Biology, Austrian Academy of Sciences, Vienna Biocenter (VBC), Vienna, 1030, Austria.
Gregor Mendel Institute of Molecular Plant Biology, Austrian Academy of Sciences, Vienna Biocenter (VBC), Vienna, 1030, Austria.
Curr Opin Plant Biol. 2022 Oct;69:102267. doi: 10.1016/j.pbi.2022.102267. Epub 2022 Aug 16.
Epigenetic mechanisms form the basis of cellular memory, developmental decisions, and the cellular immune system that defends against transposons and viruses. Organs develop from the shoot apical meristem (SAM) to shape the plant's areal phenotype, and stem cells in the SAM serve as a functional germline. While many details on the regulation of stem cell pool size, organ initiation, and patterning at the meristem periphery are known, we know surprisingly little about the molecular characteristics of SAM cells, including their epigenome and how it changes during development. Here, we summarize information on epigenetic regulation of selected genes necessary for stem cell maintenance. As recent evidence suggests that SAM stem cells might be a hotspot of transposon activation, we discuss this aspect of epigenetic control in the meristem and speculate on mechanisms that maintain the flexibility of SAM stem cells in response to developmental or environmental cues.
表观遗传机制是细胞记忆、发育决策和细胞免疫系统的基础，细胞免疫系统可以抵御转座子和病毒。器官从茎尖分生组织 (SAM) 发育而来，形成植物的面积表型，SAM 中的干细胞作为功能生殖细胞。虽然人们已经了解了许多关于干细胞池大小、器官起始和分生组织外围模式形成的调控细节，但我们对 SAM 细胞的分子特征，包括它们的表观基因组及其在发育过程中的变化，知之甚少。在这里，我们总结了维持干细胞所需的选定基因的表观遗传调控信息。最近的证据表明，SAM 干细胞可能是转座子激活的热点，因此我们讨论了这种在分生组织中表观遗传控制的方面，并推测了维持 SAM 干细胞灵活性的机制，以响应发育或环境线索。
