MicroRNA and smooth muscle cell differentiation

描述（申请人提供）：平滑肌细胞（SMC）分化的过程是血管生物学中未解决的主要问题之一。SMCs是一种高度特化的细胞类型，但在血管损伤和内膜病变形成的背景下表现出可塑性，其中存在去分化或表型调节。胚胎干细胞可以作为研究发育过程中调控细胞分化的分子机制的有效工具。在胚胎干细胞向特定细胞系分化的过程中，早期发育的各个阶段的祖细胞都会重演，这是胚胎干细胞作为研究模型的独特优势，也为我们在体外动态研究细胞分化提供了条件。最近，我们建立了小鼠ES细胞可以高效直接分化为SMC的方案，使我们能够研究SMC分化的分子机制。microRNAs （miR）是最近发现的一组小的非编码rna。miR在正常生理和病理条件下的功能已被确定，包括代谢、增殖、迁移、细胞死亡、细胞分化和发育。通过从ES细胞中建立SMC分化，我们发现miR-1在SMC分化过程中上调，而miR-141则下调。拟议的研究将检验miR-1和miR-141作为SMC分化的新关键决定因素的中心假设，利用功能增益和功能损失方法。具体而言，我们将：1)确定miR-1在SMC分化中的作用；2)确定miR-141在SMC分化中的作用；3)确定miR-1和miR-141在血管病变形成中的作用这些拟议的研究将建立一个独特的模型系统来表征miR-1和miR-141作为体外和体内SMC分化的新决定因素的中介作用。这项提议的拨款是我们确定SMC分化在血管疾病中的作用的长期目标的初始阶段。最终，我们的研究将引导我们发现新的SMC分化调节因子，并推进我们对SMC分化和血管疾病的理解。公共卫生相关性：血管生物学中未解决的主要问题之一是SMC分化的过程。最近，我们建立了小鼠ES细胞可以高效直接分化为SMC的方案，使我们能够研究SMC分化的分子机制。microRNAs （miR）是最近发现的一组小的非编码rna。miR的功能已经在正常的生理和病理条件下被确定。该提案将建立一个独特的模型系统，以表征miR-1和miR-141作为体外和体内SMC分化的新决定因素的中介作用。这项提议的拨款是我们确定SMC分化在血管疾病中的作用的长期目标的初始阶段。最终，我们的研究将引导我们发现新的SMC分化调节因子，并推进我们对SMC分化和血管疾病的理解。

DESCRIPTION (provided by applicant): One of the major unanswered questions in vascular biology is the process of smooth muscle cell (SMC) differentiation. SMCs are a highly specialized cell type yet exhibit a plasticity in which there is de-differentiation or phenotypic modulation in the context of vascular injury and intimal lesion formation. It is well established that embryonic stem (ES) cells can be utilized as an effective tool for studying the molecular mechanisms governing cell differentiation during development. During ES cell differentiation to specific cell lineage, each stage progenitor of early development will recapitulate, that is a unique advantage of ES cells subject to research model and that we can study cell differentiation dynamically in vitro. Recently, we have established a protocol that mouse ES cells can be directly differentiated to SMC with a high efficiency, which enable us to study molecular mechanisms of SMC differentiation. microRNAs (miR) are a group of recently discovered small non-coding RNAs. The functions of miR have been identified in both normal physiological and pathological conditions, including metabolism, proliferation, migration, cell death, cell differentiation and development. By establishing SMC differentiation from ES cells, we found that miR-1 is up-regulated, whereas miR-141 is downregulated during the SMC differentiation. The proposed studies will test the central hypothesis that miR-1 and miR-141 act as novel critical determinants of SMC differentiation utilizing gain- and loss-of- function approaches. Specifically, we will: 1) Determine the role of miR-1 in SMC Differentiation; 2) Determine the role of miR-141 in SMC Differentiation; and 3) Determine the Role of miR-1 and miR-141 in Vascular Lesion Formation These proposed studies will establish a unique model system for characterizing the mediator roles of miR-1 and miR-141 as novel determinants of SMC differentiation both in vitro and in vivo. This proposed grant is the initial phase of our long-term objective to define the role of SMC differentiation in vascular diseases. Ultimately, our studies will lead us to discover novel SMC differentiation regulators and advance our understanding of SMC differentiation and vascular diseases. PUBLIC HEALTH RELEVANCE: One of the major unanswered questions in vascular biology is the process of SMC differentiation. Recently, we have established a protocol that mouse ES cells can be directly differentiated to SMC with a high efficiency, which enable us to study molecular mechanisms of SMC differentiation. microRNAs (miR) are a group of recently discovered small non-coding RNAs. The functions of miR have been identified in both normal physiological and pathological conditions. This proposal will establish a unique model system for characterizing the mediator roles of miR-1 and miR-141 as novel determinants of SMC differentiation both in vitro and in vivo. This proposed grant is the initial phase of our long-term objective to define the role of SMC differentiation in vascular diseases. Ultimately, our studies will lead us to discover novel SMC differentiation regulators and advance our understanding of SMC differentiation and vascular diseases.