MYCT1 as a moderator for signaling between human HSC and their niche

MYCT1 作为人类 HSC 与其生态位之间信号传导的调节剂

基本信息

批准号：
10392239
负责人：
Hanna Katri Annikki Mikkola
金额：
$ 31.2万
依托单位：
UNIVERSITY OF CALIFORNIA LOS ANGELES
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-04-01 至 2025-02-28
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10392239
关键词：
Address Affect Biological Assay Blood Blood Cells Cell Cycle Progression Cell Line Cell division Cell physiology Cells Clinical Cues Data Endocytosis Endosomes Endothelial Cells Engraftment Environment Equilibrium Functional disorder Gene Expression Genes Hematologic Neoplasms Hematological Disease Hematopoiesis Hematopoietic Stem Cell Transplantation Hematopoietic stem cells Human Inherited Kinetics Life Link MLLT3 gene Mediating Modeling Molecular Mus Natural regeneration Patients Process Production Proteins Receptor Signaling Regulation Signal Pathway Signal Transduction TGFBR1 gene TGFBR2 gene Therapeutic Transforming Growth Factor beta Transplantation Vesicle Work clinical application ethnic bias ethnic minority extracellular gain of function hematopoietic stem cell expansion hematopoietic stem cell niche improved improved functioning insight knock-down loss of function mutant novel novel strategies overexpression prevent programs response self-renewal stem cell division stem cell function stem-like cell stemness transplantation therapy vector

项目摘要

SUMMARY Hematopoietic stem cells (HSC) need to integrate microenvironmental cues to switch their fate between quiescence, self-renewal, and differentiation, thereby sustaining hematopoiesis through life. However, the molecular programs governing HSC stemness become grossly dysregulated during culture, hindering our ability to expand functional HSCs for treating hematological diseases. Our data uncovered MYCT1 (Myc target 1) as human HSC regulatory factor that is critical for their expansion and engraftment, but becomes suppressed during differentiation and culture. We found that MYCT1 localizes in endosomes, interacts with vesicle components and signaling receptors with critical functions in HSCs (e.g. TGFBR1 and 2), and controls the rate of endocytosis, which modulates cell signaling and must be tightly regulated to maintain HSC stemness. Many genes dysregulated upon MYCT1 knockdown (KD) are linked to HSC division and self-renewal. We hypothesize that MYCT1 governs HSC stemness and their ability to balance between fate options by fine-tuning multiple signaling cues through the control of endocytosis. We have created a toolbox of MYCT1 knockdown and overexpression vectors, including various MYCT1 deletion mutants, that can be used in primary human HSPCs as well as HSC- like and endothelial cell line models to investigate MYCT1 mechanism of action. We will investigate how MYCT1- mediated control of endocytosis affects signaling in HSCs, and how this influences HSC cell-fate decisions including quiescence and asymmetric vs symmetric division. We will then assess if rescuing MYCT1 regulated processes improves the function of cultured human HSC, including those expanded using MLLT3 overexpression. Our work may open up new strategies to maintain HSC transplantability during ex vivo expansion and ultimately help broaden HSC clinical applications.

概括造血干细胞（HSC）需要整合微环境线索，以切换其命运静止，自我更新和分化，从而在生命中维持造血。但是，控制HSC茎的分子程序在培养过程中严重失调，阻碍了我们的能力扩大功能性HSC来治疗血液疾病。我们的数据将MyCt1（Myc Target 1）视为人类HSC调节因素对于其扩张和植入至关重要，但在期间被抑制分化和文化。我们发现MyCT1定位于内体中，与囊泡成分相互作用，并且在HSC中具有关键功能的信号受体（例如TGFBR1和2），并控制内吞作用速率，它调节细胞信号传导，必须严格调节以维持HSC茎。许多基因在MyCT1敲低（KD）上失调的与HSC分裂和自我更新有关。我们假设这一点 MYCT1控制HSC茎及其通过微调多重信号在命运期权之间取得平衡的能力通过控制内吞作用的线索。我们创建了一个MyCT1敲低和过表达的工具箱载体，包括各种MyCT1缺失突变体，可用于原代人HSPC以及HSC- 喜欢和内皮细胞系模型，以研究MYCT1作用机理。我们将调查如何myct1- 介导的内吞作用的控制会影响HSC中的信号传导，以及这如何影响HSC细胞的决定包括静止和不对称与对称分裂。然后，我们将评估是否拯救MyCT1监管过程改善了培养的人类HSC的功能，包括使用MLLT3扩展的过程过表达。我们的工作可能会开辟新的策略，以维持离体期间HSC的移植性扩展并最终有助于扩大HSC临床应用。