Control of Cardiac Lineage Commitment and Differentiation in Murine Development

小鼠发育中心脏谱系承诺和分化的控制

• 批准号: 8078886
• 负责人: IBRAHIM J DOMIAN
• 金额: $ 13.8万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-06-01 至 2015-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8078886
• 关键词: Adult; Advisory Committees; Affect; American; Area; Biology; Cardiac; Cardiology; Cardiovascular Diseases; Cardiovascular system; Clinical; Color; Committee Members; Congenital Abnormality; Defect; Development; Developmental Biology; Diagnosis; Disease; Doctor of Philosophy; ES Cell Line; Ectoderm; Embryo; Embryonic Development; Endoderm; Equilibrium; Event; Family; Functional RNA; Future; Gene Expression; Gene Targeting; General Hospitals; Genes; Genetic Markers; Heart; Heart Diseases; Hospitalization; Human; In Situ Hybridization; In Vitro; Institutes; Internal Medicine; Knock-in Mouse; Left ventricular structure; Massachusetts; Mentorship; Mesoderm; MicroRNAs; Molecular; Morbidity - disease rate; Morphogenesis; Mus; Myocardial; Pathway interactions; Phenotype; Physicians; Physiological; Physiology; Play; Population; Program Development; Proteins; Regenerative Medicine; Research; Research Personnel; Right ventricular structure; Role; Scientist; Small RNA; Stem cells; System; Testing; Training; Training Programs; Transgenic Mice; Transgenic Organisms; United States; Ventricular septum; Work; base; career; career development; congenital heart disorder; dosage; embryonic stem cell; homeodomain; in vivo; islet; loss of function; medical schools; mortality; progenitor; programs; public health relevance; recombinase; regenerative therapy; research study; stem cell biology; tool; transcription factor

DESCRIPTION (provided by applicant): This proposal describes a five-year training program for the development of an academic career in Cardiology. The principle investigator obtained his MD/PhD from Stanford School of Medicine and has completed clinical training in Internal Medicine, Cardiology, and Interventional Cardiology at Massachusetts General Hospital (MGH). He will now focus on the study of stem cell and developmental biology as it pertains to cardiac disease under the mentorship of Dr. Kenneth Chien. Dr. Chien, a leader in the field of cardiac development, is chief of the Cardiovascular Research Center (CVRC) at the MGH and Leader of the Cardiovascular Disease Program at the Harvard Stem Cell Institute (HSCI). He has trained numerous physician scientists. To promote training in stem cell biology, the principle investigator has already spent one year training with Dr. Stuart Orkin, a pioneer in stem cell biology. Dr. Orkin will continue to play a prominent role in training the principle investigator as an Advisory Committee member. In addition, Dr. Kenneth Bloch and Dr. Randall Peterson, both recognized leaders in cardiovascular biology, will serve mentorship roles on the Advisory Committee. The CVRC and the HSCI provide an ideal setting for training physician- scientists in the rapidly converging areas of cardiac development and stem cell biology. The research program will focus on lineage commitment and differentiation during murine cardiac development. Acquired and congenital heart disease represents a leading cause of mortality and morbidity in the world and many of the genes important in cardiac development have been implicated in human congenital heart disease. Defining the molecular pathways that control cardiac development is essential to understanding the pathophysiologic basis of these diseases and will contribute to the scientific basis of regenerative medicine. Recently, small non-coding RNA molecules called microRNAs (miRNAs) have been shown to regulate gene expression by titrating the dosage of critical proteins. Although several miRNAs are enriched in the developing heart and appear to control the balance of myocardial expansion and differentiation, the full temporal and spatial repertoire of cardiac miRNAs has yet to be established. The mammalian heart develops from two closely related sets of cardiac progenitors, first heart field (FHF) which gives rise to the left ventricle (LV) and the second heart field (SHF) which gives rise to the right ventricle (RV) and outflow tract (OFT). To investigate the role of miRNAs in controlling the development of these lineages, we have used distinct genetic markers to develop a two-color transgenic murine system. We were thereby able to purify FHF and SHF progenitors from embryos and embryonic stem cells differentiating in vitro, and to identify a set of miRNAs that are differentially expressed in the two cardiac lineages. Significantly we identify miR200a and miR200b (miR200), two closely related miRNAs transcribed in a polycistronic fashion, as the first miRNAs specific for early FHF progenitors within the developing heart and in preliminary experiments demonstrate that they appear to play a key role in the normal development of that lineage. We hypothesize that miR200 regulates cardiac development by promoting FHF progenitor expansion and differentiation and suppressing commitment to other lineages. We further hypothesize that miR200 functions by controlling specific target genes and is necessary for normal morphogenesis and function of the mature mammalian heart. To test this, we propose the following specific aims: 1) Determine if miR200 is promotes FHF development by supporting mesoderm differentiation and suppressing endoderm and ectoderm differentiation; 2) Determine the mechanisms by which miR200 controls FHF development; 3) Determine the role of miR200 during embryonic development. The tools and understanding developed here will contribute to the scientific basis of cardiac regenerative therapies. PUBLIC HEALTH RELEVANCE: Heart disease affects millions of Americans every year and is a leading cause of hospitalization in the United States. Understanding how the heart develops will help us understand how the heart becomes diseased. This study will give us clues for the future on how to diagnose and treat cardiac birth defects and adult diseases.

描述(由申请者提供)：本建议书描述了一项为期五年的心脏病学学术生涯发展培训计划。这位首席研究员在斯坦福大学医学院获得医学博士学位，并在马萨诸塞州综合医院(MGH)完成了内科、心脏病学和介入心脏病学的临床培训。他现在将在钱学森博士的指导下，专注于干细胞和发育生物学的研究，因为这与心脏病有关。钱博士是心脏开发领域的领导者，是麻省理工学院心血管研究中心(CVRC)的主任和哈佛干细胞研究所(HSCI)心血管疾病项目的负责人。他培养了许多内科科学家。为了促进干细胞生物学的培训，首席研究员已经花了一年的时间与干细胞生物学的先驱斯图尔特·奥尔金博士一起培训。奥尔金博士将继续在培训首席调查员成为咨询委员会成员方面发挥重要作用。此外，肯尼斯·布洛赫博士和兰德尔·彼得森博士都是心血管生物学领域公认的领导者，他们将在咨询委员会担任导师角色。CVRC和HSCI为在心脏发育和干细胞生物学迅速融合的领域培训内科科学家提供了理想的环境。该研究计划将重点放在小鼠心脏发育过程中的谱系承诺和分化。获得性和先天性心脏病是世界上导致死亡和发病率的主要原因，许多与心脏发育有关的基因都与人类先天性心脏病有关。明确控制心脏发育的分子途径对于了解这些疾病的病理生理学基础是至关重要的，并将有助于再生医学的科学基础。最近，被称为microRNAs(MiRNAs)的非编码小RNA分子(MiRNAs)被证明通过滴定关键蛋白质的剂量来调节基因表达。尽管一些miRNAs在发育中的心脏中丰富，似乎控制着心肌扩张和分化的平衡，但心脏miRNAs的完整时间和空间谱系尚未建立。哺乳动物心脏由两组密切相关的心脏祖细胞发育而来，第一心域(FHF)产生左心室(LV)，第二心域(SHF)产生右室(RV)和流出道(OFT)。为了研究miRNAs在控制这些谱系发育中的作用，我们使用了不同的遗传标记来开发一个双色转基因小鼠系统。因此，我们能够从体外分化的胚胎和胚胎干细胞中纯化FHF和SHF前体细胞，并鉴定出一组在这两个心脏谱系中差异表达的miRNAs。值得注意的是，我们确定了两个密切相关的miRNAs miR200a和miR200b(MiR200)，这两个miRNAs以多顺反子的方式转录，是第一个针对发育中的心脏早期FHF祖细胞的miRNAs，初步实验表明，它们似乎在该谱系的正常发育中发挥了关键作用。我们假设miR200通过促进FHF前体细胞的扩张和分化以及抑制对其他血统的承诺来调节心脏发育。我们进一步假设miR200通过控制特定的靶基因发挥作用，是成熟哺乳动物心脏正常形态发生和功能所必需的。为了验证这一点，我们提出了以下具体目标：1)确定miR200是否通过支持中胚层分化和抑制内胚层和外胚层分化来促进FHF的发育；2)确定miR200控制FHF发育的机制；3)确定miR200在胚胎发育中的作用。这里开发的工具和理解将有助于心脏再生治疗的科学基础。 公共卫生相关性：心脏病每年影响数百万美国人，是美国住院的主要原因。了解心脏是如何发展的，将有助于我们了解心脏是如何患病的。这项研究将为我们未来如何诊断和治疗心脏出生缺陷和成人疾病提供线索。