H3K36 methylation regulates cell plasticity and regeneration in the intestinal epithelium (CUT&Tag II)

Cell plasticity is needed during development and homeostasis to generate diverse cell types from stem and progenitor cells. Following differentiation, plasticity must be restricted in specialized cells to maintain tissue integrity and function. For this reason, specialized cell identity is highly stable under homeostatic conditions; however, cells in some tissues regain plasticity during injury-induced regeneration. While precise gene expression is needed to control these processes, the regulatory mechanisms that restrict or promote cell plasticity are poorly understood. Here, we use the mouse small intestine as a model system to study cell plasticity. We find that H3K36 methylation reinforces expression of cell type-associated genes to maintain specialized cell identity in intestinal epithelial cells. Depleting H3K36 methylation leads to defects in lineage commitment and activates a plastic, regenerative gene expression signature. Correspondingly, we observe rapid and reversible remodeling of H3K36 methylation following injury-induced regeneration. Together, these data suggest a fundamental role for H3K36 methylation in regulating cell plasticity and regeneration. Overall design: CUT&Tag for H3K27me3, H3K36me3, and H3K36me2 in WT H3 and H3K36M mouse intestine samples, 2 biological replicates each.

细胞可塑性(Cell plasticity)在发育与稳态过程中必不可少，可由干细胞及祖细胞分化产生多种细胞类型。细胞完成分化后，特化细胞的可塑性必须受到限制，以维持组织完整性与正常功能。正因如此，特化细胞的身份在稳态条件下高度稳定；然而，部分组织中的细胞在损伤诱导的再生过程中会重新获得可塑性。尽管精确的基因表达对调控上述过程至关重要，但限制或促进细胞可塑性的调控机制仍未得到充分解析。
本研究以小鼠小肠为模型系统，开展细胞可塑性相关研究。本研究发现，H3K36甲基化可强化细胞类型特异性基因的表达，从而维持肠上皮细胞的特化细胞身份。敲低H3K36甲基化会导致谱系定型缺陷，并激活具有可塑性的再生相关基因表达特征。相应地，我们观察到在损伤诱导的再生过程后，H3K36甲基化会发生快速且可逆的重塑。综上，本研究数据表明，H3K36甲基化在调控细胞可塑性与再生过程中发挥着基础性作用。
整体实验设计：针对野生型（wild type, WT）H3及H3K36M突变型小鼠的肠道样本，开展针对H3K27me3、H3K36me3及H3K36me2的CUT&Tag实验，每组均设置2次生物学重复。