Tse Ariana Y, Spakowitz Andrew J
Department of Materials Science, Stanford University, Stanford, CA 94305.
Department of Chemical Engineering, Stanford University, Stanford, CA 94305.
Proc Natl Acad Sci U S A. 2025 Jan 14;122(2):e2415530121. doi: 10.1073/pnas.2415530121. Epub 2025 Jan 10.
DNA methylation is a crucial epigenetic modification that orchestrates chromatin remodelers that suppress transcription, and aberrations in DNA methylation result in a variety of conditions such as cancers and developmental disorders. While it is understood that methylation occurs at CpG-rich DNA regions, it is less understood how distinct methylation profiles are established within various cell types. In this work, we develop a molecular-transport model that depicts the genomic exploration of DNA methyltransferase within a multiscale DNA environment, incorporating biologically relevant factors like methylation rate and CpG density to predict how patterns are established. Our model predicts DNA methylation-state correlation distributions arising from the transport and kinetic properties that are crucial for the establishment of unique methylation profiles. We model the methylation correlation distributions of nine cancerous human cell types to determine how these properties affect the epigenetic profile. Our theory is capable of recapitulating experimental methylation patterns, suggesting the importance of DNA methyltransferase transport in epigenetic regulation. Through this work, we propose a mechanistic description for the establishment of methylation profiles, capturing the key behavioral characteristics of methyltransferase that lead to aberrant methylation.
DNA甲基化是一种关键的表观遗传修饰,它协调抑制转录的染色质重塑因子,DNA甲基化异常会导致多种病症,如癌症和发育障碍。虽然人们知道甲基化发生在富含CpG的DNA区域,但对于如何在各种细胞类型中建立不同的甲基化图谱却了解较少。在这项工作中,我们开发了一种分子运输模型,该模型描绘了在多尺度DNA环境中DNA甲基转移酶的基因组探索过程,纳入了甲基化速率和CpG密度等生物学相关因素,以预测图谱是如何建立的。我们的模型预测了由运输和动力学特性产生的DNA甲基化状态相关分布,这些特性对于建立独特的甲基化图谱至关重要。我们对九种人类癌细胞类型的甲基化相关分布进行建模,以确定这些特性如何影响表观遗传图谱。我们的理论能够重现实验甲基化模式,表明DNA甲基转移酶运输在表观遗传调控中的重要性。通过这项工作,我们提出了一种关于甲基化图谱建立的机制描述,捕捉了导致异常甲基化的甲基转移酶的关键行为特征。