Post-transcriptional mechanisms of gene regulation in cardiac cell growth and development

心肌细胞生长发育中基因调控的转录后机制

• 批准号: 8859710
• 负责人: Auinash Kalsotra
• 金额: $ 38.68万
• 依托单位: UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2020-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8859710
• 关键词: Address; Adult; Affect; American; Binding; Binding Proteins; Binding Sites; Biochemical; Biological; Biological Assay; Cardiac; Cardiac Myocytes; Cell Culture Techniques; Cells; Coupled; Coupling; Data; Development; Embryo; Employee Strikes; Fetal Heart; Fractionation; Gene Expression Regulation; Genes; Genetic Translation; Goals; Growth; Growth and Development function; Heart; Heart Diseases; Heart Function Tests; Heart Hypertrophy; Heart failure; High-Throughput Nucleotide Sequencing; Histology; Human; Hypertrophy; Immunofluorescence Immunologic; Immunoprecipitation; In Vitro; Individual; Laboratories; Length; Life; Messenger RNA; Molecular; Molecular Biology; Mus; Myocardial; Myocardial Infarction; Neonatal; Nuclear; Outcome; Pathologic; Pathology; Play; Poly A; Poly(A) Tail; Poly(A)-Binding Proteins; Polynucleotide Adenylyltransferase; Polyribosomes; Population; Positioning Attribute; Proteins; Public Health; Regulator Genes; Research; Resistance; Ribosomes; Role; Stress; Structure; Testing; Tetracyclines; Tissues; Transcript; Transgenic Mice; Transgenic Organisms; Translating; Translation Initiation; Translations; Up-Regulation; base; cardiogenesis; cell growth; cell type; fetal; insight; mRNA Export; mouse model; multidisciplinary; next generation sequencing; novel; novel therapeutics; polyadenosine; polyadenylated messenger RNA; postnatal; protein expression; public health relevance; response; translation assay

 DESCRIPTION (provided by applicant): For many genes, steady state mRNA levels provide an inaccurate reflection of the extent to which they are translated into proteins. The factors influencing the translation of individual mRNAs during cardiac hypertrophy are poorly understood. Our objective is to determine the function of the cytosolic polyA-binding protein C1 (PABPC1) as a novel regulator of cardiac hypertrophy. PABPC1 selectively binds to the 3'- poly(A) tail sequence of most eukaryotic mRNAs and is critical for their overall translation and turnover. We demonstrate that PABPC1 protein levels in mice and humans are post-transcriptionally suppressed during postnatal heart development. Importantly, PABPC1 protein levels increase during cardiac hypertrophy, and we show that PABPC1 depleted mouse cardiac myocytes are resistant to pathologic hypertrophy. To directly test the role of PABPC1 in cardiac hypertrophy, we have developed a tetracycline-inducible and cardiac-specific PABPC1 transgenic mouse model. Further, we demonstrate that the poly(A) tail length of Pabpc1 mRNAs decreases during heart development, which is consistent with its reduced association with polysomes and poor translation. More significantly, we have discovered other stable, distinct, populations of short poly(A) tail containing mRNAs in adult hearts of mice and humans. The Specific Aims of this proposal are to: (1) Identify mechanism(s) that control cell-type specific expression of PABPC1; (2) Determine the requirement of PABPC1 in hypertrophic growth of cardiac cells; and (3) Determine the role of PABPC1 in modulating the poly(A) tail length and translation control of its target mRNAs in heart. We will use a combination of molecular, biochemical, transgenic and high-throughput sequencing approaches to address these important questions. PUBLIC HEALTH RELVANCE: This proposal will establish a new gene regulatory mechanism based on regulated changes in poly(A) tail length influencing the efficiency with which subset of cardiac mRNAs are translated. This project will also dissect the functional role of a poly(A) binding protein in stimulation of cardiac hypertrophy, a condition that is involved in number of heart diseases. Successful completion of the proposed research will produce detailed understanding of an unexplored mechanism of gene regulation and will open exciting new therapeutic opportunities to treat cardiac hypertrophy and its associated pathologies that affect millions of Americans.

 描述（由适用提供）：对于许多基因，稳态mRNA水平提供了将它们转化为蛋白质的程度的不准确反射。影响心脏肥大过程中单个mRNA翻译的因素知之甚少。我们的目标是确定胞质多蛋白结合蛋白C1（PABPC1）作为心脏肥大的新调节剂的功能。 PABPC1选择性地结合了大多数真核mRNA的3'- poly（a）尾序，对于它们的整体翻译和周转至关重要。我们证明，在产后心脏发育期间，小鼠和人类的PABPC1蛋白水平在转录后受到抑制。重要的是，PABPC1蛋白水平在心脏肥大期间升高，我们表明PABPC1加深了小鼠心肌细胞对病理肥大的抗性。为了直接测试PABPC1在心脏肥大中的作用，我们开发了四环素诱导和心脏特异性PABPC1转基因小鼠模型。此外，我们证明了PABPC1 mRNA的聚（a）尾部长度在心脏发育过程中降低，这与其与多聚体和不良翻译的关联减少一致。更重要的是，我们发现了其他稳定的，独特的，短多（A）的尾巴，这些尾巴含有小鼠和人类成年心脏中的mRNA。该提案的具体目的是：（1）确定控制PABPC1特异性表达的机制； （2）确定PABPC1对心脏细胞肥厚性生长的需求； （3）确定PABPC1在调节心脏中靶标mRNA的尾部长度和翻译控制中的作用。我们将结合分子，生化，转基因和高通量测序方法来解决这些重要问题。 公共卫生关系：该提案将基于poly（a）尾部长度的调节变化的效率建立一种新的基因调节机制，该效率会翻译出心脏mRNA的子集。该项目还将剖析多（a）结合蛋白在刺激心脏肥大中的功能作用，心脏疾病与心脏病的数量有关。成功完成拟议的研究将对基因调节的意外机制产生详细的理解，并为治疗心脏肥大及其相关病理的兴奋新的治疗机会及其影响数百万美国人的相关病理。