RNA-binding protein CRD-BP in melanocyte biology

黑素细胞生物学中的 RNA 结合蛋白 CRD-BP

• 批准号: 8616719
• 负责人: Vladimir S. Spiegelman
• 金额: $ 31.64万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-02-11 至 2018-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8616719
• 关键词: Address; Binding; Biological Assay; Biology; Cell Culture Techniques; Controlled Environment; Data; Development; Differentiation and Growth; Embryo; Environment; Evaluation; Foundations; Gene Expression; Genes; Genetic Transcription; Goals; Growth; Growth and Development function; Hypoxia; IGF2 gene; Knock-out; Knowledge; Light; Malignant - descriptor; Messenger RNA; MicroRNAs; Mus; Physiological; Play; Prevention; RNA-Binding Proteins; Regulation; Role; Signal Pathway; Signal Transduction; Site; Skin; Trans-Activators; Transcript; Untranslated Regions; Up-Regulation; Zebrafish; base; c-myc Genes; cis acting element; mRNA Decay; mRNA Stability; melanocyte; melanoma; microphthalmia-associated transcription factor; novel; prevent; public health relevance; response; tau Proteins; transcription factor; ultraviolet irradiation

DESCRIPTION (provided by applicant): The goal of studies proposed here is to understand the role of the role of RNA-binding protein, CRD-BP, in melanocyte biology. Microphtalmia-associated transcription factor (MITF) is a principal regulator of melanocyte development and a pivotal factor in the survival and growth of malignant melanomas. Therefore understanding the mechanisms controlling the expression and function of MITF is extremely important as it will identify key components for melanocyte development, and differentiation. Regulation of mRNA turnover emerged in recent years as a major mechanism controlling gene expression. mRNA decay rates are responsive to developmental and environmental signals and dictated by cis-acting elements within the mRNA and by trans-acting factors, such as miRNAs and RNA-binding proteins. We have shown that MITF mRNA is a novel melanocyte/melanoma-specific target of CRD-BP. We demonstrated that CRD-BP directly binds to the 3'-UTR of MITF mRNA and prevents the binding of miR-340 to its target sites resulting in stabilization of the MITF transcript that leads to induction of MITF expression and activities. CRD-BP is a multifunctional RNA-binding protein that recognizes the mRNAs of MITF, bTrCP1, Gli1, c-myc, IGF2, tau, and other genes. We identified CRD-BP as a novel target of b-catenin/Tcf, and c-myc transcription factors. Our preliminary data demonstrate that in response to b-catenin signaling, CRD-BP binds and stabilizes mRNAs of c-myc and bTrCP1. CRD-BP is essential for induction of c-myc and bTrCP1 by b-catenin signaling. Transcriptional upregulation of CRD-BP by b-catenin/Tcf may therefore contribute to pleiotropic effects of the Wnt signaling pathway and could provide the foundation for the hypothesis that CRD-BP might have a significant function in Wnt/b-catenin-dependent melanocyte development. In addition to the regulation by Wnt signaling, our preliminary results show that hypoxia also induces the expression of CRD-BP. Taking into consideration the physiologically hypoxic environment of the skin, this novel mode of regulation of expression and function of CRD-BP could play a significant role in melanocyte growth and development. We hypothesize that by influencing the stability of MITF and other mRNAs, CRD-BP is essential for normal melanocyte development. We propose to study the role of CRD-BP in melanocyte biology, and the mechanisms and significance of its regulation in melanocytes. Pursuant to these goals, the specific aims are: 1. To define the requirement for CRD-BP in the growth and differentiation of melanocytes. 2. To delineate the mechanism(s) of CRD-BP regulation by hypoxia. 3. To analyze the (patho)physiologic significance of CRD-BP regulation by hypoxia in melanocytes.

描述（由申请人提供）：这里提出的研究的目的是了解RNA结合蛋白CRD-BP在黑素细胞生物学中的作用。与微茶质相关的转录因子（MITF）是黑素开发的主要调节剂，也是恶性黑色素瘤存活和生长的关键因子。因此，了解控制MITF的表达和功能的机制非常重要，因为它将确定黑素细胞发育和分化的关键组成部分。近年来作为控制基因表达的主要机制出现了mRNA周转的调节。 mRNA衰变速率对发育和环境信号有反应，并取决于mRNA中的顺式作用元素和跨作用因子（例如miRNA和RNA结合蛋白）。我们已经证明MITF mRNA是CRD-BP的新型黑色素细胞/黑色素瘤特异性靶标。我们证明，CRD-BP直接与MITF mRNA的3'-UTR结合，并防止miR-340与其目标位点结合，从而导致MITF转录本稳定，从而导致MITF表达和活性诱导。 CRD-BP是一种多功能的RNA结合蛋白，识别MITF，BTRCP1，GLI1，C-MYC，IGF2，TAU和其他基因的mRNA。我们将CRD-BP确定为B-Catenin/TCF的新靶标和C-MYC转录因子。我们的初步数据表明，在响应B-catenin信号传导时，CRD-BP结合并稳定C-MYC和BTRCP1的mRNA。 CRD-BP对于通过B-catenin信号传导诱导C-MYC和BTRCP1至关重要。因此，B-catenin/TCF对CRD-BP的转录上调可能有助于Wnt信号通路的多效性效应，并可以为CRD-BP在WNT/B-catenin依赖性黑色素细胞的发育中具有重要功能的假说提供基础。除了通过WNT信号传导调控外，我们的初步结果表明，缺氧还诱导了CRD-BP的表达。考虑到皮肤的生理缺氧环境，这种新颖的CRD-BP表达和功能调节方式可能在黑素细胞的生长和发育中起重要作用。我们假设通过影响MITF和其他mRNA的稳定性，CRD-BP对于正常的黑素细胞发育至关重要。我们建议研究CRD-BP在黑素细胞生物学中的作用，以及其在黑素细胞中调节的机制和意义。根据这些目标，具体的目的是：1。定义CRD-BP在黑素细胞生长和分化方面的要求。 2。描述缺氧调节CRD-BP的机制。 3。分析黑素细胞中缺氧CRD-BP调控的（病情）生理意义。