Anchored Kinase Signaling Mechanisms in Cardiac Hypertrophy

心脏肥大中的锚定激酶信号传导机制

• 批准号: 8230792
• 负责人: John D Scott
• 金额: $ 43.4万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-03-01 至 2014-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8230792
• 关键词: A kinase anchoring protein; Antibodies; Binding; Biomechanics; Cardiac; Cardiac Myocytes; Catecholamines; Cause of Death; Complex; Cyclic AMP-Dependent Protein Kinases; Disease; Enhancers; Enzymes; Event; Figs - dietary; Funding; Genetic Transcription; HDAC5 gene; Heart; Heart Diseases; Heart Hypertrophy; Heart Valve Diseases; Heart failure; Histone Deacetylase; Human; Hypertension; Hypertrophy; Image; Knock-in Mouse; Measures; Mediating; Molecular; Monitor; Movement; Mus; Muscle Cells; Neonatal; Nuclear; Nuclear Export; Pathway interactions; Pattern; Phosphorylation; Phosphotransferases; Population; Protein Biosynthesis; Protein Kinase C; Proteins; Rattus; Risk Factors; Sarcomeres; Signal Pathway; Signal Transduction; Signaling Protein; Stimulus; Stress; Testing; Time; Tissues; Transcriptional Activation; United States; Western World; Work; in vivo; member; protein kinase D; protein protein interaction; response; theories

DESCRIPTION (provided by applicant): Heart failure is a complex disorder that is a leading cause of death in the Western world. Approximately 5 million people (2-3 % of the population) are afflicted with this disease in the United States. Increased risk factors such as arterial hypertension and valvular heart diseases place additional biomechanical stress on the heart to induce a cellular response known as pathological cardiomyocyte hypertrophy. Hallmarks of this condition include increased cardiomyocyte size and a greater organization of the sarcomere. At the molecular level, hypertrophic signals such as elevated catecholamines evoke transcriptional activation of the Myocyte Enhancer Factor (MEF2) pathway to change the pattern of protein synthesis. During the past funding period we have begun to decipher some of the protein-protein interactions that contribute to the spatial and temporal modulation of the MEF2 pathway. We have identified an A-Kinase Anchoring protein, called AKAP-Lbc that coordinates the activation and movement of the signaling proteins that initiate MEF2 mediated transcriptional reprogramming events. Our working hypothesis is that AKAP-Lbc synchronizes protein kinase A (PKA) and protein kinase C (PKC) phosphorylation events to facilitate activation of a third enzyme, called protein kinase D (PKD). In turn, PKD phosphorylates the histone deacetylase HDAC5 to promote its nuclear export. Finally, the concomitant reduction in nuclear HDAC activity favors MEF2 transcription and the onset of cardiac hypertrophy. Two specific aims are proposed to test this hypothesis. Specific aim 1: Does AKAP-Lbc organize transcriptional reprogramming? Our preliminary studies show that AKAP-Lbc supports PKD activation and favors nuclear export of HDAC5. Real-time fluorescent imaging will be used to establish if the anchoring protein organizes both signaling events in rat neonatal ventriculocytes (RNV). Related studies will measure MEF2 transcription upon disruption of protein-protein interactions between members of the AKAP/Lbc-PKD/HDAC pathway. Specific aim 2: Does the AKAP-Lbc/PKD/HDAC5 pathway contribute to heart disease? We propose that the AKAP-Lbc/PKD/HDAC5 pathway facilitates the onset of cardiac hypertrophy. Two complementary approaches will test this theory in vivo. Activation state antibodies will monitor the status of the AKAP-Lbc/PKD/HDAC pathway in normal and diseased human heart tissue. Analysis of knock in mice expressing a truncated AKAP-Lbc form that blocks PKD activation will determine if suppression of this signaling pathway protects against certain aspects of cardiac remodeling. Within the United States approximately 5 million people are afflicted with heart failure, a complex disorder that is a leading cause of death. Increased biomechanical stress on the heart induces a cellular response known as pathological cardiomyocyte hypertrophy. We have identified an A-Kinase Anchoring protein, called AKAP-Lbc that is up regulated in hypertrophic cardiomyocytes and that coordinates the activation and movement of signaling proteins upstream of MEF2-mediated transcriptional reprogramming events.

描述（由申请人提供）：心力衰竭是一种复杂的疾病，是西方世界死亡的主要原因。在美国，大约有 500 万人（占人口的 2-3%）患有这种疾病。动脉高血压和瓣膜性心脏病等危险因素的增加会给心脏带来额外的生物力学压力，从而诱发称为病理性心肌细胞肥大的细胞反应。这种情况的标志包括心肌细胞大小增加和肌节组织更大。在分子水平上，肥大信号（例如儿茶酚胺升高）会引起肌细胞增强因子（MEF2）途径的转录激活，从而改变蛋白质合成的模式。在过去的资助期间，我们已经开始破译一些蛋白质-蛋白质相互作用，这些相互作用有助于 MEF2 通路的空间和时间调节。我们已经鉴定出一种 A 激酶锚定蛋白，称为 AKAP-Lbc，它协调信号蛋白的激活和运动，从而启动 MEF2 介导的转录重编程事件。我们的工作假设是 AKAP-Lbc 同步蛋白激酶 A (PKA) 和蛋白激酶 C (PKC) 磷酸化事件，以促进第三种酶（称为蛋白激酶 D (PKD)）的激活。反过来，PKD 磷酸化组蛋白脱乙酰酶 HDAC5 以促进其核输出。最后，核 HDAC 活性的降低有利于 MEF2 转录和心脏肥大的发生。提出了两个具体目标来检验这一假设。 具体目标 1：AKAP-Lbc 是否组织转录重编程？我们的初步研究表明 AKAP-Lbc 支持 PKD 激活并有利于 HDAC5 的核输出。实时荧光成像将用于确定锚定蛋白是否组织大鼠新生心室细胞（RNV）中的两个信号事件。相关研究将在 AKAP/Lbc-PKD/HDAC 通路成员之间的蛋白质-蛋白质相互作用破坏时测量 MEF2 转录。 具体目标 2：AKAP-Lbc/PKD/HDAC5 通路是否会导致心脏病？我们提出 AKAP-Lbc/PKD/HDAC5 通路促进心脏肥大的发生。两种互补的方法将在体内测试这一理论。激活状态抗体将监测正常和患病人类心脏组织中 AKAP-Lbc/PKD/HDAC 通路的状态。对表达截短的 AKAP-Lbc 形式（可阻断 PKD 激活）的小鼠进行敲击分析，将确定抑制该信号通路是否可以防止心脏重塑的某些方面。在美国，大约有 500 万人患有心力衰竭，这是一种复杂的疾病，是导致死亡的主要原因。心脏生物力学压力的增加会引起一种称为病理性心肌细胞肥大的细胞反应。我们已经鉴定出一种 A 激酶锚定蛋白，称为 AKAP-Lbc，它在肥大心肌细胞中上调，并协调 MEF2 介导的转录重编程事件上游信号蛋白的激活和运动。

项目成果

AKAP signaling complexes: pointing towards the next generation of therapeutic targets?

• DOI: 10.1016/j.tips.2013.10.005
• 发表时间: 2013-12
• 期刊: TRENDS IN PHARMACOLOGICAL SCIENCES
• 影响因子: 13.8
• 作者: Esseltine, Jessica L.;Scott, John D.
• 通讯作者: Scott, John D.

Integrating cardiac PIP3 and cAMP signaling through a PKA anchoring function of p110γ.

• DOI: 10.1016/j.molcel.2011.01.030
• 发表时间: 2011-04-08
• 期刊: Molecular cell
• 影响因子: 16
• 作者: Perino A;Ghigo A;Ferrero E;Morello F;Santulli G;Baillie GS;Damilano F;Dunlop AJ;Pawson C;Walser R;Levi R;Altruda F;Silengo L;Langeberg LK;Neubauer G;Heymans S;Lembo G;Wymann MP;Wetzker R;Houslay MD;Iaccarino G;Scott JD;Hirsch E
• 通讯作者: Hirsch E

Anchoring proteins as regulators of signaling pathways.

• DOI: 10.1161/circresaha.111.262899
• 发表时间: 2012-08-03
• 期刊: Circulation research
• 影响因子: 20.1
• 作者: Perino A;Ghigo A;Scott JD;Hirsch E
• 通讯作者: Hirsch E

Full-length cardiac Na+/Ca2+ exchanger 1 protein is not phosphorylated by protein kinase A.

• DOI: 10.1152/ajpcell.00196.2010
• 发表时间: 2011-02
• 期刊: American journal of physiology. Cell physiology
• 作者: P. Wanichawan;W. Louch;K. H. Hortemo;B. Austbø;P. Lunde;John D. Scott;O. Sejersted;C. Carlson

A-kinase anchoring proteins: from protein complexes to physiology and disease.

• DOI: 10.1002/iub.168
• 发表时间: 2009-04
• 期刊: IUBMB LIFE
• 影响因子: 4.6
• 作者: Carnegie, Graeme K.;Means, Christopher K.;Scott, John D.
• 通讯作者: Scott, John D.