Role of let-7 microRNAs in skeletal development

let-7 microRNA 在骨骼发育中的作用

基本信息

批准号：
7639797
负责人：
TATSUYA KOBAYASHI
金额：
$ 23.27万
依托单位：
MASSACHUSETTS GENERAL HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-04-01 至 2011-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7639797
关键词：
Animals Biogenesis Biological Biological Process Cartilage Cell Differentiation process Cell Proliferation Chondrocytes Data Defect Development Disease Excision Family Functional RNA Gene Expression Gene Expression Regulation Gene Targeting Genes Genetic Genomics Goals Human Individual Life Mammals MicroRNAs Mus Neoplasm Metastasis Organism Pathology Phase I Clinical Trials Phenotype Physiological Physiology Play Process RNA-Binding Proteins Regulation Research Role Skeletal Development Skeletal system Stem cells System Therapeutic Therapeutic Intervention Time Tissues Transcript Transgenic Mice base cancer cell cancer stem cell cartilage development gain of function gene function human DICER1 protein human disease in vivo insight loss of function novel overexpression public health relevance self-renewal skeletal skeletal disorder skeletal tissue skeletogenesis stemness tool

项目摘要

DESCRIPTION (provided by applicant): The small regulatory RNAs, microRNAs (miRNAs), play important biological roles in various types of living organisms. In humans, defects in miRNA-dependent gene regulation are implicated in several diseases. Despite these facts, functions of miRNAs in the mammalian skeletal system have barely been studied. The let-7 family miRNAs constitute the largest potion of chondrocytic miRNAs. let-7 miRNAs regulate diverse biological functions that include regulation of developmental timing, cell proliferation and differentiation, cancer metastasis, and stem cell self-renewal. However, the physiological role of let-7 miRNAs in skeletal development is unknown. The goal of this research is to establish the role of let-7 miRNAs during skeletogenesis. We will investigate the role of let-7 miRNAs in the mouse skeletal system by suppressing and overexpressing let-7 miRNAs. In mice, let-7 miRNAs are encoded at 8 genomic loci. This extensive genetic multiplicity makes it difficult to perform a loss-of-function study using the conventional gene targeting strategy. To suppress multiple let-7 miRNAs in a tissue-specific fashion, we will misexpress the RNA-binding protein, Lin28, in the cartilage using a Cre-dependent binary system. Lin28 specifically inhibits processing of primary transcripts of let-7 miRNAs and thereby suppresses let-7 expression. The consequences of Lin28 misexpression in mice will be analyzed. In Aim II, functions of let-7 miRNAs will be investigated by a gain-of-function study. let-7 miRNAs will be overexpressed in the cartilage using the same binary gene expression system. let-7 will also be co-expressed with Lin28 to determine the specific function of Lin28. This project should provide insights into the physiological role of let-7 miRNAs in skeletogenesis. In addition, the Cre-dependent expression systems for Lin28 and let-7 will be useful tools for studying the function of these genes in other tissues. Understanding of individual miRNAs is necessary for the development of potential miRNA-based treatment of skeletal diseases. PUBLIC HEALTH RELEVANCE: The small regulatory RNAs, microRNAs regulate gene expression mainly at the post transcriptional level. let-7 microRNAs are the most abundant miRNA species in skeletal tissues. However, the physiological roles of let-7 miRNAs in skeletal tissues are unknown. This project aims to elucidate let-7 function in the mouse skeletal system using novel genetic tools. Understanding roles of individual miRNAs will provide a basis for potential therapeutic interventions for skeletal diseases.

描述（由申请人提供）：小调节RNA、微小RNA（miRNA）在各种类型的活生物体中发挥着重要的生物学作用。在人类中，miRNA 依赖性基因调控的缺陷与多种疾病有关。尽管存在这些事实，但 miRNA 在哺乳动物骨骼系统中的功能却几乎没有被研究过。 let-7 家族 miRNA 构成了软骨细胞 miRNA 中最大的部分。 let-7 miRNA 调节多种生物学功能，包括调节发育时间、细胞增殖和分化、癌症转移和干细胞自我更新。然而，let-7 miRNA 在骨骼发育中的生理作用尚不清楚。本研究的目标是确定 let-7 miRNA 在骨骼发生过程中的作用。我们将通过抑制和过度表达let-7 miRNA来研究let-7 miRNA在小鼠骨骼系统中的作用。在小鼠中，let-7 miRNA 在 8 个基因组位点编码。这种广泛的遗传多样性使得使用传统的基因靶向策略很难进行功能丧失研究。为了以组织特异性方式抑制多个 let-7 miRNA，我们将使用 Cre 依赖性二元系统在软骨中错误表达 RNA 结合蛋白 Lin28。 Lin28 特异性抑制 let-7 miRNA 初级转录物的加工，从而抑制 let-7 表达。将分析 Lin28 错误表达在小鼠中的后果。在 Aim II 中，将通过功能获得研究来研究 let-7 miRNA 的功能。 let-7 miRNA 将使用相同的二元基因表达系统在软骨中过度表达。 let-7还将与Lin28共表达，以确定Lin28的具体功能。该项目应该能够深入了解 let-7 miRNA 在骨骼发生中的生理作用。此外，Lin28 和 let-7 的 Cre 依赖性表达系统将成为研究这些基因在其他组织中的功能的有用工具。了解单个 miRNA 对于开发潜在的基于 miRNA 的骨骼疾病治疗方法是必要的。公共卫生相关性：小调控 RNA、microRNA 主要在转录后水平调节基因表达。 let-7 microRNA 是骨骼组织中最丰富的 miRNA 种类。然而，let-7 miRNA 在骨骼组织中的生理作用尚不清楚。该项目旨在利用新型遗传工具阐明小鼠骨骼系统中 let-7 的功能。了解单个 miRNA 的作用将为骨骼疾病的潜在治疗干预提供基础。