母体多梳印记通过低阶甲基化状态在果蝇早期发育中得以维持
A maternal Polycomb imprint is maintained in early Drosophila development through lower-order methylation states.
摘要(中文译文)
Polycomb群（PcG）蛋白通过促进H3赖氨酸27的单、二和三甲基化（H3K27me1/2/3）来调控胚胎表观遗传状态。为使合子继承母源H3K27甲基化状态，卵子发生过程中建立的PcG修饰必须存续至合子基因组激活。亲本PcG状态是否贯穿果蝇胚胎发生过程尚不清楚。本研究将随机建模与体内实验相结合，以明确母源H3K27甲基化的命运。我们发现，所继承的PcG状态由宽泛的非经典H3K27me2/3结构域组成，且H3K27me3在卵裂过程中并未得以维持，而是丢失并在经典PcG结构域内 later 重新建立。相比之下，H3K27me2以顺式方式在母源染色质上持续存在。建模与遗传分析表明，这种保留与Polycomb抑制复合物2（PRC2）变构依赖性维持相一致，而非非特异性、成核非依赖性甲基化。这些发现提示，早期胚胎继承的母源H3K27景观主要以H3K27me2形式持续存在，随后被重塑为经典H3K27me3结构域。
Abstract
Polycomb group (PcG) proteins regulate embryonic epigenetic states by facilitating mono-, di-, and tri-methylation of H3 lysine 27 (H3K27me1/2/3). For the zygote to inherit a maternal H3K27 methylation state, PcG modifications established during oogenesis must survive until zygotic genome activation. Whether parental PcG states persist through Drosophila embryogenesis remains unclear. Here, we combine stochastic modeling with in vivo experiments to define the fate of maternal H3K27 methylation. We find that the inherited PcG state consists of broad, non-canonical H3K27me2/3 domains and that H3K27me3 is not maintained through cleavage divisions but lost and later re-established within canonical PcG domains. In contrast, H3K27me2 persists in cis on maternal chromatin. Modeling and genetic analyses indicate that this retention is consistent with Polycomb repressive complex 2 (PRC2) allostery-dependent maintenance rather than non-specific, nucleation-independent methylation. These findings suggest that the early embryo inherits a maternal H3K27 landscape that persists primarily as H3K27me2 and is later remodeled into canonical H3K27me3 domains.
如何引用
AMA
Eleanor A Degen, Natalie Gonzaga-Saavedra, Shelby A Blythe. A maternal Polycomb imprint is maintained in early Drosophila development through lower-order methylation states.. Cell reports. 2026; doi:10.1016/j.celrep.2026.117679.
APA
Eleanor A Degen, Natalie Gonzaga-Saavedra, Shelby A Blythe (2026). A maternal Polycomb imprint is maintained in early Drosophila development through lower-order methylation states.. Cell reports. https://doi.org/10.1016/j.celrep.2026.117679
GB/T 7714
Eleanor A Degen, Natalie Gonzaga-Saavedra, Shelby A Blythe. A maternal Polycomb imprint is maintained in early Drosophila development through lower-order methylation states.[J]. Cell reports, 2026 doi:10.1016/j.celrep.2026.117679.
在 PubMed增强版 阅读全文
翻译全文 · AI 文献问答 · PDF 原文下载 · 引用导出