RUNX@ Subnuclear Targeting Integrates Signaling Pathways for Bone Formation

RUNX@ 亚核靶向整合骨形成信号通路

• 批准号: 8289359
• 负责人: Jane B. Lian
• 金额: $ 38.85万
• 依托单位: UNIV OF MASSACHUSETTS MED SCH WORCESTER
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-01 至 2013-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8289359
• 关键词: 3-Dimensional; Adaptor Signaling Protein; Address; Affect; Aging; Amino Acids; Animal Model; Architecture; BMP2 gene; Biological; Biological Process; Bone Development; Bone Matrix; Bone Tissue; Calvaria; Cell Culture Techniques; Cell Lineage; Cell Nucleus; Cells; Chromatin Remodeling Factor; Clinical; Co-Immunoprecipitations; Collaborations; Complement; Complex; Coupled; DNA Binding Domain; Data Set; Development; Diagnosis; Disease; Environment; Enzymes; Gene Expression; Gene Targeting; Genes; Hereditary Disease; Hormones; In Situ; In Vitro; Intervention; Knock-in Mouse; Mediating; Mediator of activation protein; Metabolic Bone Diseases; MicroRNAs; Modeling; Mus; Mutation; Nuclear; Nuclear Localization Signal; Nuclear Matrix; Null Lymphocytes; Ohio; Osteoblasts; Osteogenesis; Osteoporosis; Phenotype; Point Mutation; Post-Transcriptional Regulation; Post-Translational Protein Processing; Process; Production; Program Research Project Grants; Proteins; Recruitment Activity; Regulation; Regulator Genes; Role; Runx2 protein; Scaffolding Protein; Secondary to; Signal Pathway; Signal Transduction; Signaling Protein; Site; Skeleton; Small Interfering RNA; Staging; Technology; Tertiary Protein Structure; Therapeutic; Time; Tissue-Specific Gene Expression; Transactivation; Universities; Validation; Vitamin D; Work; base; bone; bone cell; bone loss; bone mass; cDNA Arrays; cell growth; chromatin modification; clinically relevant; genetic regulatory protein; human DICER1 protein; in vivo; mouse model; mutant; novel; osteoblast differentiation; osteogenic; overexpression; programs; promoter; protein complex; reconstitution; response; skeletal; skeletal disorder; stem cell differentiation; therapeutic target; transcription factor

Runx2 is a scaffolding protein that interacts with proteins representing many different functional classes, including chromatin remodeling factors, proteins coupled to cell growth control, differentiation of osteoblasts and production of bone matrix, as well as those proteins that transduce developmental signaling pathways for bone formation. We have established that Runx2 recruits to its subnuclear domains associated with the nuclear matrix, intracellular mediators of signaling pathways that are both positive and negative regulators of bone formation, including Smads in response to BMP/TGF(3, and YAP, a WW domain protein in response to Src signaling. We have defined specific point mutations in the Runx2 protein that can disrupt these critical interactions between Runx2 and Smad and Runx2 with WW domain proteins, which include a growing number of factors that influence Runx2 activity on target genes. These point mutations allow us to address the in vivo significance of these interactions in nuclear microenvironments in mouse knock-in models. Our discovery of miRNAs that affect osteoblast differentiation leads us to address how micro-RNAs (miRNA) that target Runx2 and Runx2 co-factors regulate bone formation through modification of the proteins that form Runx2 coregulatory complexes in the nucleus. Project 2 will now pursue how these multiple signaling pathways which converge on Runx2 are regulated during osteoblast differentiation for the control of bone formation. We will 1) characterize Runx2-Smad target genes and regulatory complexes required to complete the BMP2 osteogenic signal; 2) characterize the biological mechanisms and signaling pathways influencing the organization of WW coregulatory proteins with Runx2 to control osteogenesis; and Aim 3) investigate how miRNA candidates that target Runx2 and coregulatory factors regulate osteogenesis. Clinical Relevance: There is a pressing need to develop anabolic therapies for treating bone loss in osteoporosis from the aging skeleton or induced secondary to a metabolic bone disorder. Our studies will define novel targets that produce new bone in response to BMPs, shift the stem cell differentiation towards the osteoblast lineage and identify miRNA regulators of bone formation. Each of these represents potential therapeutic applications to stimulate osteoblast differentiation and bone formation. For example, siRNA and miRNA technologies are being developed for in vivo application. Anabolic therapies that are safer than hormone treatments could be developed for stimulating bone formation.

Runx2 是一种支架蛋白，可与代表许多不同功能类别的蛋白质相互作用， 包括染色质重塑因子、与细胞生长控制偶联的蛋白质、成骨细胞的分化 和骨基质的产生，以及转导发育信号通路的蛋白质 用于骨骼形成。我们已经确定 Runx2 招募到与 核基质，信号通路的细胞内介质，既是正调节因子又是负调节因子 骨形成，包括响应 BMP/TGF(3 的 Smads 和响应 BMP/TGF(3 的 WW 结构域蛋白 YAP) Src 信令。我们已经在 Runx2 蛋白中定义了特定的点突变，可以破坏这些关键的 Runx2 和 Smad 以及 Runx2 与 WW 结构域蛋白之间的相互作用，其中包括生长的 影响 Runx2 对靶基因活性的因素。这些点突变使我们能够解决 小鼠敲入模型中核微环境中这些相互作用的体内意义。我们的 影响成骨细胞分化的 miRNA 的发现引导我们解决 micro-RNA (miRNA) 如何影响成骨细胞分化的问题。 目标 Runx2 和 Runx2 辅助因子通过修饰形成的蛋白质来调节骨形成 细胞核中的 Runx2 核心调节复合物。项目 2 现在将研究这些多重信号如何 汇聚于 Runx2 的通路在成骨细胞分化过程中受到调节，以控制骨 形成。我们将 1) 描述完成所需的 Runx2-Smad 靶基因和调控复合物 BMP2成骨信号； 2）表征影响的生物学机制和信号通路 WW 共调节蛋白与 Runx2 的组织以控制成骨；目标 3) 调查 靶向 Runx2 和辅助调节因子的 miRNA 候选物如何调节成骨。 临床相关性：迫切需要开发合成代谢疗法来治疗骨丢失 骨骼老化引起的骨质疏松症或继发于代谢性骨病引起的骨质疏松症。我们的研究将 定义响应 BMP 产生新骨的新靶标，将干细胞分化转向 成骨细胞谱系并鉴定骨形成的 miRNA 调节因子。每一个都代表着潜力 刺激成骨细胞分化和骨形成的治疗应用。例如，siRNA和 miRNA 技术正在开发用于体内应用。比合成代谢疗法更安全的 可以开发激素治疗来刺激骨形成。