MicroRNAs in small intestinal epithelial cell proliferation and differentiation

MicroRNA在小肠上皮细胞增殖和分化中的作用

• 批准号: 8331596
• 负责人: Anne Mathea Hutson
• 金额: $ 13.73万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2013-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8331596
• 关键词: 3' Untranslated Regions; Address; Advisory Committees; American; Animals; Area; Award; Binding; Biology; Biomedical Research; Cancer Center; Cell Differentiation process; Cell Line; Cell Maturation; Cell Proliferation; Cell physiology; Cells; Collaborations; Colorectal Cancer; Computer Simulation; Data; Detection; Disease; Enterocytes; Epithelial Cell Proliferation; Epithelial Cells; Experimental Designs; Floor; Funding; Gastroenterology; Gastrointestinal Physiology; Gene Expression; Gene Expression Regulation; Health; Hepatology; In Vitro; Intestinal Diseases; Intestines; Journals; K-Series Research Career Programs; Literature; Liver; Luciferases; Malignant Neoplasms; Manuscripts; Mediating; Mentors; Messenger RNA; Methodology; Methods; MicroRNAs; Modeling; Mus; Nature; Northern Blotting; Pediatrics; Physiological; Physiology; Play; Postdoctoral Fellow; Productivity; Proteins; Publications; Published Comment; Publishing; Reporter; Research; Research Personnel; Resources; Reverse Transcriptase Polymerase Chain Reaction; Role; Secretory Cell; Site; Small Intestines; Small RNA; Techniques; Testing; Therapeutic Agents; Time; Tissues; Training; Translations; Villus; Work; base; calin; career; cell growth; cell type; crypt cell; gene repression; high risk; inhibitor/antagonist; intestinal epithelium; leukemia/lymphoma; member; mouse model; nutrition; pediatric department; professor; programs; repaired; response; self-renewal; skills; transcription factor; tumorigenic

DESCRIPTION (provided by applicant): The small intestinal epithelium is constantly undergoing self-renewal. Intestinal epithelial cells migrate from the crypts, the site of cell proliferation, to the villi, where terminally differentiated absorptive enterocytes and secretory cells function. microRNAs (miRNAs) are a relatively new class of regulatory RNAs essential for cell proliferation and differentiation in all animal cell types and tissues studied. miRNAs generally repress gene expression by binding the 3'-untranslated region (3'UTR) of target mRNAs. I have identified 12 miRNAs that are differentially expressed in villi vs. crypts of the mouse small intestine. These miRNAs may play a role in regulating proliferation and differentiation of intestinal epithelial cells. For my first Aim, sythetic [sic] miRNA mimics and inhibitors will be used to test the ability of these miRNAs to alter intestinal cell growth and maturation in vitro. Also, I found that the crypt-enriched miR-152 is predicted to target Klf4, a transcription factor expressed in differentiated intestinal epithelial cells. Therefore, in my second Aim I will determine if miR-152 represses Klf4 expression with miRNA mimics and inhibitors in intestinal cell lines, and with a luciferase reporter construct that has the 3'UTR of Klf4 cloned downstream from luciferase. Additionally, the villus-enriched miR-22 is highly expressed in the small intestine. Through a collaboration, a miR-22(-/-) mouse is available to me to study miR-22 function in the intestine. In Aim 3, I will look for mRNA targets of miR-22 in villus and crypt cells by expression array. These data will be combined with in silico predictions to help identify miR-22 targets. miR-22(-/-) mice will also be crossed with Apc(min/+) mice, a model of colorectal cancer, to determine if loss of miR-22 is tumorigenic. These data and techniques will form the basis for my independent research program to investigate mechanisms of miRNA-mediated gene repression in the small intestine. My mentors Dr. Douglas Burrin (intestinal physiology) and Dr. George Calin (miRNA biology), and the members of my scientific advisory committee, including Dr. Susan Henning, are experts in areas relevant to my proposal. The training I receive through this award will enable me to develop the skills and expertise needed for a career in biomedical research. PUBLIC HEALTH RELEVANCE: This work will advance our understanding of gene regulation in the intestine. Small RNA molecules are already being tested as therapeutic agents. Thus, knowing the miRNAs important for intestinal epithelial cell proliferation and differentiation and identifying their targets could help us find new treatments for intestinal diseases such as intestinal bowel disease and cancer, and for promoting intestinal regrowth and repair.

描述（由申请人提供）： 小肠上皮不断进行自我更新。肠上皮细胞从隐窝（细胞增殖的部位）迁移到绒毛，在绒毛中终末分化的吸收性肠上皮细胞和分泌细胞发挥功能。microRNA（miRNAs）是一类相对较新的调控RNA，在所有研究的动物细胞类型和组织中对细胞增殖和分化至关重要。miRNA通常通过结合靶mRNA的3 '-非翻译区（3' UTR）来抑制基因表达。我已经鉴定了12种在小鼠小肠绒毛和隐窝中差异表达的miRNA。这些miRNAs可能在调节肠上皮细胞增殖和分化中发挥作用。对于我的第一个目标，合成的[sic] miRNA模拟物和抑制剂将用于测试这些miRNA在体外改变肠细胞生长和成熟的能力。此外，我发现富含隐窝的miR-152被预测为靶向Klf 4，Klf 4是一种在分化的肠上皮细胞中表达的转录因子。因此，在我的第二个目标中，我将确定miR-152是否在肠细胞系中与miRNA模拟物和抑制剂一起抑制Klf 4表达，以及与具有克隆在荧光素酶下游的Klf 4的3 'UTR的荧光素酶报告基因构建体一起抑制Klf 4表达。此外，绒毛富集的miR-22在小肠中高度表达。通过合作，miR-22（-/-）小鼠可用于研究miR-22在肠道中的功能。目的3：利用表达芯片技术在绒毛和隐窝细胞中寻找miR-22的靶基因。这些数据将与计算机预测相结合，以帮助确定miR-22靶点。miR-22（-/-）小鼠也将与Apc（min/+）小鼠（结直肠癌模型）杂交，以确定miR-22的缺失是否是致瘤性的。这些数据和技术将为我的独立研究计划奠定基础，以研究小肠中miRNA介导的基因抑制机制。我的导师道格拉斯·伯林博士（肠道生理学）和乔治·卡林博士（miRNA生物学），以及我的科学顾问委员会成员，包括苏珊·亨宁博士，都是与我的提议相关领域的专家。我通过这个奖项获得的培训将使我能够发展生物医学研究职业所需的技能和专业知识。 公共卫生相关性：这项工作将促进我们对肠道基因调控的理解。小RNA分子已经作为治疗剂进行了测试。因此，了解对肠上皮细胞增殖和分化重要的miRNAs并确定其靶点可以帮助我们找到治疗肠道疾病（如肠道疾病和癌症）以及促进肠道再生和修复的新方法。