MicroRNA and smooth muscle cell differentiation

描述（由申请人提供）：血管生物学中的一个主要未回答的问题是平滑肌细胞（SMC）分化过程。SMC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去分化或表型调节的可塑性。胚胎干细胞是研究发育过程中细胞分化的分子机制的有效工具。在ES细胞向特定细胞谱系分化的过程中，早期发育的各个阶段祖细胞都会重演，这是ES细胞作为研究模型的独特优势，可以在体外动态研究细胞分化。近年来，我们建立了小鼠ES细胞高效直接分化为SMC的方法，为进一步研究SMC分化的分子机制奠定了基础。microRNA（miR）是近年来发现的一类小的非编码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细胞建立SMC分化，我们发现miR-1在SMC分化过程中上调，而miR-141在SMC分化过程中下调。拟议的研究将利用功能获得和功能丧失方法来检验中心假设，即miR-1和miR-141作为SMC分化的新的关键决定因素。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;和3）确定miR-1和miR-141在血管病变形成中的作用这些提出的研究将建立一个独特的模型系统，用于表征miR-1和miR-141作为SMC分化的新决定因素在体外和体内的介导作用。这项拟议的拨款是我们长期目标的初始阶段，以确定SMC分化在血管疾病中的作用。最终，我们的研究将引导我们发现新的SMC分化调节剂，并促进我们对SMC分化和血管疾病的理解。公共卫生相关性：血管生物学中尚未回答的主要问题之一是SMC分化过程。近年来，我们建立了小鼠ES细胞高效直接分化为SMC的方法，为进一步研究SMC分化的分子机制奠定了基础。microRNA（miR）是近年来发现的一类小的非编码RNA。在正常生理和病理条件下，miR的功能已经被确定。该方案将建立一个独特的模型系统，用于表征miR-1和miR-141作为SMC分化的新决定因素在体外和体内的介导作用。这项拟议的拨款是我们长期目标的初始阶段，以确定SMC分化在血管疾病中的作用。最终，我们的研究将引导我们发现新的SMC分化调节剂，并促进我们对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.