Role of Id genes during cardiac development

Id 基因在心脏发育过程中的作用

• 批准号: 6769226
• 负责人: DIEGO FRAIDENRAICH
• 金额: $ 13.33万
• 依托单位: SLOAN-KETTERING INST CAN RESEARCH
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-06-01 至 2009-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6769226
• 关键词: DNA binding protein; biological signal transduction; cardiogenesis; cell differentiation; cell growth regulation; developmental genetics; embryonic stem cell; endocardium; gene expression; gene mutation; genetically modified animals; laboratory mouse; myocardium; pericardium; polymerase chain reaction; protein isoforms; protein structure; protein transport; southern blotting; tissue /cell culture; transcription factor

DESCRIPTION (provided by applicant): The goal of this proposal is to address the role of the Id (inhibitor of differentiation) genes in specific cardiac compartments during development. Idl, 2 and 3 are expressed in the developing heart in the developing epicardium, endocardium and endocardial cushions (ECs), but not in the myocardium. Idl, Id2 or Id3 gene ablation studies revealed no developmental defects, but Idlld3, Idl Id2 and Id21d3 double mutant embryos die by E13.5. Ablation of Idl-3 in varying combinations resulted in cardiac defects not only in the endocardium and in the ECs, but also in the myocardium, suggesting cross-communication between layers. Id deficient embryos displayed impaired trabeculae and interventricular septum, thin myocardial wall, stenotic outflow tract, disorganized endocardium and hypocellular ECs. Injection of LacZ-marked Embryonic Stem (ES) cells reversed the cardiac abnormalities and rescued the embryonic lethality of the Idlld3 KO embryos. Altered myocardial markers in the Id KO embryos are restored to normal in the mutant cells of the rescued hearts. Thus, The ES-derived cells display the capacity to reverse gene expression profiles in mutant cells in a non-cell autonomous fashion. These observations raise important biological questions: What is the role of Id in the epicardium, endocardium/EC and in the myocardium? Is the Id mode of action non-cell autonomous? Which are the Id-dependent signals involved in the cross-talk between cardiac layers? Aiming to answer these questions we propose to study the role of Id genes in adult hearts of rescued chimeras (AIM I), to study the requirement for Id genes in specific cardiac compartments (AIM II), and to identify key mediators of Id signaling (AIM III). We will use murine models to extend the studies conducted with ES cells. Additionally, we will generate conditional KO and tissue-specific transgenic models. Some of the experiments will be complemented by tissue culture studies. The Sloan-Kettering Institute for Cancer Research provides the appropriate environment required to carry out this project, including the mouse transgenic, genomics core, and histology core facilities. The long term goals are to develop murine models to better understand the role of developmental control genes in cardiac formation, how mutations in those genes lead to congenital heart disease, and how these abnormalities could be prevented or ameliorated by embryonic stem cell injection. These studies may have important implications for congenital heart disease.

描述（由申请人提供）： 该提案的目标是解决Id（分化抑制剂）基因在发育过程中特定心脏隔室中的作用。Idl、2和3在发育中的心脏中在发育中的心外膜、内膜和内膜垫（EC）中表达，但不在心肌中表达。Idl、Id 2或Id 3基因切除研究显示没有发育缺陷，但Idlld 3、Idl Id 2和Id 21 d3双突变胚胎在E13.5死亡。Idl-3在不同组合中的消融不仅在内皮细胞和EC中导致心脏缺陷，而且在心肌中导致心脏缺陷，这表明层之间的交叉通信。Id缺陷胚胎表现为心肌小梁和室间隔受损、心肌壁变薄、流出道狭窄、内皮细胞排列紊乱和细胞减少。注射LacZ标记的胚胎干（ES）细胞逆转了心脏异常并挽救了Idlld 3 KO胚胎的胚胎致死率。 Id KO胚胎中改变的心肌标志物在获救心脏的突变细胞中恢复正常。因此，ES衍生的细胞显示出以非细胞自主方式逆转突变细胞中基因表达谱的能力。这些观察结果提出了重要的生物学问题：Id在心外膜、内膜/EC和心肌中的作用是什么？ID的作用模式是否为非细胞自主？心脏各层之间的串扰涉及哪些ID依赖性信号？为了回答这些问题，我们建议研究Id基因在获救嵌合体（AIM I）的成年心脏中的作用，研究特定心脏隔室（AIM II）对Id基因的需求，并确定Id信号传导的关键介质（AIM III）。我们将使用小鼠模型来扩展用ES细胞进行的研究。此外，我们将产生条件KO和组织特异性转基因模型。一些实验将通过组织培养研究来补充。Sloan-Kettering癌症研究所提供了开展该项目所需的适当环境，包括小鼠转基因、基因组学核心和组织学核心设施。长期目标是开发小鼠模型，以更好地了解发育控制基因在心脏形成中的作用，这些基因的突变如何导致先天性心脏病，以及如何通过胚胎干细胞注射预防或改善这些异常。这些研究可能对先天性心脏病有重要意义。