Embryonic stem cell self-renewal

胚胎干细胞自我更新

• 批准号: 9912157
• 负责人: Qilong Ying
• 金额: $ 33万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-08-01 至 2022-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9912157
• 关键词: Affect; Amino Acids; Biologic Development; Cell Culture Techniques; Cell Nucleus; Cells; Chemicals; Cytoplasm; Data; Development; Disease; Disease model; Extracellular Signal Regulated Kinases; Functional disorder; Gene Deletion; Glycogen Synthase Kinase 3; Goals; Gold; Human; Individual; Inner Cell Mass; MAPK1 gene; MAPK3 gene; Mammals; Mediating; Mitogen-Activated Protein Kinase Kinases; Modeling; Molecular; Mus; Pathologic; Phenotype; Phosphotransferases; Physiological; Play; Pluripotent Stem Cells; Process; Protein Kinase; Proteins; Rattus; Regenerative Medicine; Research; Role; Signal Pathway; Signal Transduction; Technology; Testing; Time; Work; base; beta catenin; cell type; chemical genetics; embryonic stem cell; gene function; genetic approach; human disease; human model; inhibitor/antagonist; innovation; insight; kinase inhibitor; member; natural Blastocyst Implantation; novel; paralogous gene; preimplantation; scaffold; self-renewal; small molecule; stem cell fate; success; therapy development; tool; transmission process

Embryonic stem cells (ESCs) are pluripotent stem cells derived from the inner cell mass of the pre-implantation blastocyst. ESCs provide a powerful platform for elucidating gene function and creating disease models. So far, the application of ESC-based technologies has been limited to mice and rats, because germline competent ESCs have not yet been established from non-rodent species. Our previous work established that efficient self- renewal of mouse and rat ESCs could be achieved by dual inhibition of glycogen synthase kinase 3 (GSK3) and mitogen-activated protein kinase kinase (MEK). GSK3 has two paralogous members, GSK3α and GSKβ, which share nearly identical kinase domains. Similarly, extracellular signal-regulated kinase (ERK), the only known physiological substrates of MEK, also has two highly homologous paralogs, ERK1 and ERK2. Despite their high levels of homology, GSK3α and GSK3β possess distinct functions in regulating ESC self-renewal; the same is the case for ERK1 and ERK2. Therefore, fine-tuning of GSK3 and ERK signaling becomes critical in achieving optimal ESC self-renewal. By taking advantage of the chemical-genetic approach and the ESC platform, we propose to investigate the molecular mechanisms underlying the distinct functions of individual GSK3 and ERK paralogs in ESC self-renewal. In Aim 1, we will identify and characterize GSK3 paralog- specific substrates and downstream targets. We will also determine the amino acid variances responsible for the distinct functions of GSK3α and GSK3β. In Aim 2, we will identify and characterize ERK paralog-specific substrates in the cytoplasm and nucleus and investigate how subcellular localization of ERK1 and ERK2 affects their functions in ESCs. In Aim 3, we will fine-tune GSK3 and ERK signaling in mouse and human naïve ESCs to achieve optimal self-renewal effect. Success with these three aims will not only provide insights into the molecular basis of ESC self-renewal, but will also have far-reaching implications for our deep understanding of pathological conditions caused by dysfunction of GSK3 and ERK.

胚胎干细胞（embryonic stem cells，ESCs）是从着床前胚胎的内细胞团中分离出来的多能干细胞， 胚泡胚胎干细胞为阐明基因功能和建立疾病模型提供了一个强大的平台。到目前为止， 基于胚胎干细胞的技术的应用仅限于小鼠和大鼠， 尚未从非啮齿动物物种中建立ESC。我们以前的工作建立了有效的自我- 通过双重抑制糖原合成酶激酶3（GSK 3）， 和促分裂原活化蛋白激酶激酶（MEK）。GSK 3有两个旁系同源成员，GSK 3 α和GSK β， 它们共享几乎相同的激酶结构域。同样，细胞外信号调节激酶（ERK），唯一的 MEK的已知生理底物也具有两种高度同源的旁系同源物，ERK 1和ERK 2。尽管 GSK 3 α和GSK 3 β具有高度同源性，在调节ESC自我更新中具有不同的功能; ERK1和ERK2也是如此。因此，GSK3和ERK信号转导的微调变得至关重要 实现最佳ESC自我更新。通过利用化学遗传学方法和ESC 平台，我们建议研究个体不同功能的分子机制， ESC自我更新中的GSK3和ERK旁系同源物。在目标1中，我们将鉴定和表征GSK3蛋白， 特定底物和下游靶点。我们还将确定氨基酸差异， GSK 3 α和GSK 3 β的不同功能。在目标2中，我们将鉴定和表征ERK旁系同源特异性 底物的细胞质和细胞核，并探讨如何亚细胞定位的ERK 1和ERK 2 影响其在ESC中的功能。在目标3中，我们将在小鼠和人的幼稚细胞中微调GSK3和ERK信号传导。 ESCs以达到最佳的自我更新效果。这三个目标的成功不仅将提供对以下方面的见解： ESC自我更新的分子基础，但也将对我们的深层 了解由GSK3和ERK功能障碍引起的病理状况。