SR Ca2+ ATPase, a determinant of cardiac contractility

SR Ca2 ATP酶，心肌收缩力的决定因素

• 批准号: 7159348
• 负责人: Muthu Periasamy
• 金额: $ 35.44万
• 依托单位: OHIO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-01-15 至 2009-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7159348
• 关键词: ATP phosphohydrolase; ATP2A2; Adenoviruses; Adrenergic Agents; Adult; Affect; Affinity; Alleles; Amino Acids; C-terminal; Ca(2+)-Transporting ATPase; CaMKII phosphatase; Calcium; Cardiac; Cardiac Myocytes; Chronic; Clinical; Complex; Cyclic AMP-Dependent Protein Kinases; Data; Equilibrium; Exons; Frequencies; Functional disorder; Gel; Gene Transfer; Genes; Heart; Heart failure; Homeostasis; Human; Hypertrophy; Ions; Knock-out; Localized; Macromolecular Complexes; Maps; Mass Spectrum Analysis; Mediating; Membrane; Modeling; Mus; Muscle Cells; Myocardium; Partner in relationship; Phosphoric Monoester Hydrolases; Phosphorylation; Play; Precipitation; Principal Investigator; Protein Kinase; Protein Overexpression; Proteins; Pump; Rate; Rattus; Regulation; Role; SERCA2a; Site; Staging; Structure-Activity Relationship; Transgenic Animals; adenoviral-mediated; adrenergic; enzyme activity; knockout gene; mouse model; novel; promoter; recombinase; response; sarcolipin; uptake

DESCRIPTION (provided by applicant): Decreased SERCA pump expression and activity have been implicated in diastolic dysfunction and heart failure. To better define the role of decreased SERCA pump expression we developed a SERCA2 gene knockout (-/+) model. However, heterozygous mice (born with only a single functional allele of the SERCA2 gene) induce several compensatory alterations in expression and activity of other Ca2+ handling proteins to make up a decrease in SERCA pump function. Thus, a chronic reduction in SERCA2 activity results in a new equilibrium set point for the regulation of cardiomyocyte Ca2+ homeostasis. To overcome this problem we will develop a Conditional knockout (cKO) mouse model to ablate the SERCA2 gene in a heart specific and inducible manner in adult stages. Studies also indicate that SERCA2a and 2b are co-expressed in the heart and SERCA2b can substitute for SERCA2a function. Compared with SERCA2a, SERCA2b has 49 extra C-terminal amino acids and has a higher Ca2+ affinity and lower turnover rate. We hypothesize that SERCA2b plays a unique role in SR Ca2+ uptake (because of its high apparent affinity for Ca2+ ion) and is important for maintaining low cytosolic Ca2+ content. To define the role of SERCA2b we will use adenoviral-mediated SERCA gene transfer into adult rat myocytes. In addition, we have preliminary data to suggest that SERCA protein either forms a complex or co-localizes with its regulatory molecules (PLB, sarcolipin, PKA, CaMKII, Phosphatase 1 and 2a, tethered via anchoring molecules) for efficient regulation of SR Ca2+ uptake function. In this proposal we seek to identify the SERCA macromolecular complex using immuno-precipitations and 2D gel analyses and MASS spectrometry. Collectively, these studies will allow us to better understand the role of SERCA2a and 2b pumps in the beat-to-beat function of the myocardium. As such, these studies are likely to suggest novel clinical strategies that might be pursued for the management of chronic heart failure in humans.

描述（由申请人提供）：SERCA泵表达和活性降低与舒张功能障碍和心力衰竭有关。为了更好地定义降低的SERCA泵表达的作用，我们开发了SERCA 2基因敲除（-/+）模型。然而，杂合子小鼠（出生时仅具有SERCA 2基因的单个功能等位基因）诱导其他Ca 2+处理蛋白的表达和活性的几种补偿性改变，以弥补SERCA泵功能的降低。因此，SERCA 2活性的慢性降低导致用于调节心肌细胞Ca 2+稳态的新的平衡设定点。为了克服这个问题，我们将开发一种条件性敲除（cKO）小鼠模型，以在成年阶段以心脏特异性和可诱导的方式消融SERCA 2基因。研究还表明，SERCA 2a和2b在心脏中共表达，SERCA 2b可以替代SERCA 2a的功能。与SERCA 2a相比，SERCA 2b的C-末端多了49个氨基酸，并具有更高的钙离子亲和力和更低的周转率。我们假设SERCA 2b在SR Ca 2+摄取中起着独特的作用（因为其对Ca 2+离子的高表观亲和力），并且对于维持低细胞溶质Ca 2+含量很重要。为了定义SERCA 2b的作用，我们将使用腺病毒介导的SERCA基因转移到成年大鼠肌细胞中。此外，我们有初步的数据表明，SERCA蛋白要么形成一个复合物，要么与其调节分子（PLB，sarcolipin，PKA，CaMKII，磷酸酶1和2a，通过锚定分子栓系）共定位，以有效地调节SR Ca 2+摄取功能。在这个建议中，我们试图确定使用免疫沉淀和二维凝胶分析和质谱法的SERCA大分子复合物。总的来说，这些研究将使我们能够更好地了解SERCA 2a和2b泵在心肌搏动功能中的作用。因此，这些研究很可能提出新的临床策略，可用于人类慢性心力衰竭的管理。

项目成果

Threonine-5 at the N-terminus can modulate sarcolipin function in cardiac myocytes.

N 末端的苏氨酸-5 可以调节心肌细胞中的肌磷脂功能。

• DOI: 10.1016/j.yjmcc.2009.07.014
• 发表时间: 2009-11
• 期刊: Journal of molecular and cellular cardiology
• 影响因子: 5
• 作者: Bhupathy P;Babu GJ;Ito M;Periasamy M
• 通讯作者: Periasamy M

Adenoviral-mediated serca gene transfer into cardiac myocytes: how much is too much?

腺病毒介导的 serca 基因转移至心肌细胞：多少才算太多？

• DOI: 10.1161/01.res.88.4.373
• 发表时间: 2001
• 期刊: Circulation research
• 影响因子: 20.1
• 作者: Periasamy,M

Molecular basis of diastolic dysfunction.

• DOI: 10.1016/j.hfc.2007.10.007
• 发表时间: 2008-01-01
• 期刊: Heart failure clinics
• 影响因子: 3.4
• 作者: Periasamy, Muthu;Janssen, Paul M L
• 通讯作者: Janssen, Paul M L

Transgenic mouse models for cardiac dysfunction by a specific gene manipulation.

通过特定基因操作产生心脏功能障碍的转基因小鼠模型。

• DOI: 10.1385/1-59259-879-x:365
• 发表时间: 2005
• 期刊: Methods in molecular medicine
• 作者: Babu,GopalJ;Periasamy,Muthu
• 通讯作者: Periasamy,Muthu

Functional consequences of stably expressing a mutant calsequestrin (CASQ2D307H) in the CASQ2 null background.

在 CASQ2 无效背景中稳定表达突变型 calsequestrin (CASQ2D307H) 的功能后果。

• DOI: 10.1152/ajpheart.00578.2011
• 发表时间: 2012
• 期刊: American journal of physiology. Heart and circulatory physiology
• 作者: Kalyanasundaram,Anuradha;Viatchenko-Karpinski,Serge;Belevych,AndriyE;Lacombe,VeroniqueA;Hwang,HyunSeok;Knollmann,BjörnC;Gyorke,Sandor;Periasamy,Muthu
• 通讯作者: Periasamy,Muthu