The DNA methylome-based regulation of functional beta-cell mass

基于 DNA 甲基化组的功能性 β 细胞群调节

• 批准号: 10647908
• 负责人: Guoqiang Gu
• 金额: $ 44.31万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10647908
• 关键词: Acute; Address; Affect; Age Months; Aging; Attenuated; Beta Cell; Birth; Cell Differentiation process; Cell Lineage; Cell Proliferation; Cell physiology; Cells; DNA; DNA Methylation; DNA Modification Methylases; DNA Sequence Alteration; DNMT3a; Darkness; Data; Derivation procedure; Development; Diabetes Mellitus; Diet; Dioxygenases; Disease; Down-Regulation; Embryo; Embryonic Development; Endocrine; Enhancers; Enzymes; Epigenetic Process; Exposure to; Future; Gene Expression; Genes; Genetic; Genetic Polymorphism; Glucose; Goals; Human; Hyperglycemia; Hypoglycemia; Immunocompromised Host; Insulin Resistance; Islet Cell; Link; Maintenance; Metabolic stress; Methylation; Modeling; Molecular; Mus; Non-Insulin-Dependent Diabetes Mellitus; Nutrient; Pancreas; Pattern; Physiological; Physiology; Positioning Attribute; Predisposition; Process; Production; Proliferating; Protein-Restricted Diet; Publishing; Regulation; Repression; Risk Factors; Role; Sentinel; Specific qualifier value; Stress; Testing; Text; allotransplant; combinatorial; demethylation; dosage; fitness; genomic locus; improved; innovation; insulin secretion; islet stem cells; methylome; mother nutrition; offspring; postnatal; prenatal exposure; prevent; progenitor; programs; stem cells; synaptotagmin VII; transcription factor; transcriptome

Insufficient functional β-cell mass can cause type 2 diabetes (T2D). This application will elucidate how the DNA methylomes in embryonic multipotent pancreatic progenitor cells (mPPCs) pre-determine this mass. During embryogenesis, mPPCs activate pro-endocrine transcription factor (TF) Ngn3 to give rise to endocrine progenitor cells (EPCs), from which β cells are derived. DNA methylation is a relatively stable repressive mark that is laid down by several enzymes including DNA methyl-transferase 1 (Dnmt1). DNMT1 polymorphisms are associated with attenuated β-cell function and human T2D. We show that fetal exposure to maternal low-protein diet, known to compromise functional β-cell mass, enhances Dnmt1 expression in mouse mPPCs. We recently published that both mPPC and EPC pools can be split into subsets that carry different DNA methylation levels at likely instructive gene enhancers, which can bias islet-cell fate choice. Moreover, higher Dnmt1 expression in mPPCs/EPCs favors β-cell differentiation; yet EPC differentiation toward islet cells involves a rapid and substantial downregulation of Dnmt1 and concordant de-methylation in putative enhancers of genes that regulate β-cell proliferation and function (referred to as fitness). The latter includes Synaptotagmin 7 (Syt7), a gene that promotes glucose-stimulated insulin secretion. Our model is that the methylomes in mPPCs can influence the evolving methylomes in their descendant EPCs and β cells. Thus, mPPCs with distinct methylomes can give rise to β-cell subsets with different fitness by pre-setting the expression levels of genes that will be activated later for high β-cell fitness qualities. Perturbing the early-stage methylomes, by changed Dnmt1 expression and/or maternal diet manipulation, will shift the portions of β-cell subsets and consequently the functional β-cell mass and the susceptibility to T2D. Consistent with this model, we showed that a portion (~55%) of β cells derived from a subset of Ngn3+ EPCs that co-express TF Myt1 (i.e., Myt1+Ngn3+ or “M+N+”) has higher postnatal fitness than those from M-N+ cells under normal physiology. Here, we will first define the fitness of M+N+ or M-N+ progenitor-derived β-cell subsets under metabolic stresses such as aging, hyperglycemia, or insulin resistance to elucidate their physiological significance (Am 1). We will then examine the transcriptomes/methylomes of the two subsets to define the key methylated loci that can account for their distinct β-cell fitness, including testing if the differential Syt7 expression in the two β-cell subsets (observed by us) contributes to their different insulin secretion activities (Aim 2). Lastly, we will examine how maternal low-protein diet exposure impacts the derivation and fitness of M+N+ and M-N+ progenitor-derived β-cell subsets, focusing on the roles of enhanced Dnmt1 expression in mPPCs (Aim 3). We expect to impact the field by establishing direct mechanistic links between maternal factors and genetic networks that regulate functional β-cell mass and susceptibility to T2D. Our innovative combinatorial lineage marking of β-cell subsets put us in a unique position to study these issues.

功能性 β 细胞质量不足可能导致 2 型糖尿病 (T2D)。该应用将阐明胚胎多能胰腺祖细胞 (mPPC) 中的 DNA 甲基化如何在胚胎发生过程中预先确定该质量。 ) Ngn3 产生内分泌祖细胞 (EPC)，β 细胞的 DNA 甲基化相对稳定。由包括 DNA 甲基转移酶 1 (DNMT1) 在内的多种酶产生的抑制标记与 β 细胞功能减弱和人类 T2D 相关。 -细胞质量，增强小鼠 mPPC 中的 Dnmt1 表达，我们最近发表了 mPPC 和 EPC 池都可以分为携带不同 DNA 甲基化水平的子集。此外，mPPCs/EPCs 中较高的 Dnmt1 表达有利于 β 细胞分化；然而 EPC 向胰岛细胞的分化涉及 Dnmt1 的快速且大幅下调和一致的去甲基化。调节 β 细胞增殖和功能（称为适应性）的基因的推定增强子包括 Synaptotagmin 7 (Syt7)，一种促进基因。我们的模型是，mPPC 中的甲基化组可以影响其后代 EPC 和 β 细胞中的甲基化组，因此，具有不同甲基化组的 mPPC 可以通过预设表达来产生具有不同适应性的 β 细胞亚群。通过改变 Dnmt1 表达和/或母体饮食控制，扰乱早期甲基化组，将改变稍后将被激活以实现高 β 细胞适应性的基因水平。部分 β 细胞以及功能性 β 细胞团和对 T2D 的易感性与该模型一致，我们表明一部分 (~55%) β 细胞源自共表达 TF Myt1 的 Ngn3+ EPC 子集。 （即 Myt1+Ngn3+ 或“M+N+”）在正常生理条件下比 M-N+ 细胞具有更高的产后适应度。这里，我们首先定义 的适应度。 M+N+ 或 M-N+ 祖细胞衍生的 β 细胞亚群在衰老、高血糖或胰岛素抵抗等代谢应激下，以阐明其生理意义 (Am 1)。可以解释其独特的 β 细胞适应性的关键甲基化位点，包括测试两个 β 细胞亚群（我们观察到的）中的差异 Syt7 表达是否导致其不同的胰岛素分泌活动（目标 2），我们将研究母亲低蛋白饮食暴露如何影响 M+N+ 和 M-N+ 祖细胞衍生的 β 细胞亚群的衍生和适应性，重点关注 mPPC 中增强的 Dnmt1 表达的作用（目标 2）。 3) 我们希望通过在母体因素和调节功能性 β 细胞质量和 T2D 易感性的遗传网络之间建立直接的机制联系来影响该领域。 β细胞亚群使我们处于研究这些问题的独特地位。

项目成果

Glucose-stimulated KIF5B-driven microtubule sliding organizes microtubule networks in pancreatic beta cells.

葡萄糖刺激的 KIF5B 驱动的微管滑动在胰腺 β 细胞中组织微管网络。

• 发表时间: 2023-06-26
• 作者: Bracey, Kai M;Noguchi, Pi'illani;Edwards, Courtney;Cario, Alisa;Gu, Guoqiang;Kaverina, Irina
• 通讯作者: Kaverina, Irina

Microtubules and Gαo-signaling modulate the preferential secretion of young insulin secretory granules in islet β cells via independent pathways.

微管和Gαo 信号通过独立途径调节胰岛β 细胞中年轻胰岛素分泌颗粒的优先分泌。

• 发表时间: 2021
• 影响因子: 3.7
• 作者: Hu, Ruiying;Zhu, Xiaodong;Yuan, Mingyang;Ho, Kung;Kaverina, Irina;Gu, Guoqiang
• 通讯作者: Gu, Guoqiang

A developmental lineage-based gene co-expression network for mouse pancreatic β-cells reveals a role for Zfp800 in pancreas development.

小鼠胰腺β细胞的基于发育谱系的基因共表达网络揭示了Zfp800在胰腺发育中的作用。

• 发表时间: 2021
• 作者: Osipovich, Anna B;Dudek, Karrie D;Greenfest;Cartailler, Jean;Manduchi, Elisabetta;Potter Case, Leah;Choi, Eunyoung;Chapman, Austin G;Clayton, Hannah W;Gu, Guoqiang;Stoeckert Jr, Christian J;Magnuson, Mark A
• 通讯作者: Magnuson, Mark A

Myt Transcription Factors Prevent Stress-Response Gene Overactivation to Enable Postnatal Pancreatic β Cell Proliferation, Function, and Survival.

Myt 转录因子可防止应激反应基因过度激活，从而促进出生后胰腺 β 细胞的增殖、功能和存活。

• 发表时间: 2020-06-22
• 影响因子: 11.8
• 作者: Hu, Ruiying;Walker, Emily;Huang, Chen;Xu, Yanwen;Weng, Chen;Erickson, Gillian E;Coldren, Anastasia;Yang, Xiaodun;Brissova, Marcela;Kaverina, Irina;Balamurugan, Appakalai N;Wright, Christopher V E;Li, Yan;Stein, Roland;Gu, Guoqiang
• 通讯作者: Gu, Guoqiang

Microtubules regulate pancreatic β-cell heterogeneity via spatiotemporal control of insulin secretion hot spots.

微管通过时空控制胰岛素分泌热点来调节胰腺β细胞异质性。

• 发表时间: 2021
• 影响因子: 7.7
• 作者: Trogden, Kathryn P;Lee, Justin;Bracey, Kai M;Ho, Kung;McKinney, Hudson;Zhu, Xiaodong;Arpag, Goker;Folland, Thomas G;Osipovich, Anna B;Magnuson, Mark A;Zanic, Marija;Gu, Guoqiang;Holmes, William R;Kaverina, Irina
• 通讯作者: Kaverina, Irina