The role of tropomyosin phosphorylation in muscle.

原肌球蛋白磷酸化在肌肉中的作用。

• 批准号: 6994009
• 负责人: Brandon J Biesiadecki
• 金额: $ 4.83万
• 依托单位: UNIVERSITY OF ILLINOIS AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-08-16 至 2007-08-15
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6994009
• 关键词: SDS polyacrylamide gel electrophoresis; actins; calcium flux; cardiac myocytes; densitometry; gelsolin; heart contraction; laboratory mouse; matrix assisted laser desorption ionization; microfilaments; muscle metabolism; myocardial ischemia /hypoxia; myocardium; myosins; papillary muscles; phosphoproteins; phosphorylation; postdoctoral investigator; posttranslational modifications; protein binding; protein protein interaction; tropomyosin; two dimensional gel electrophoresis

DESCRIPTION (provided by applicant): The experiments proposed in this study investigate the hypothesis that tropomyosin phosphorylation (Tm-P) in the heart is altered by cardiac stress and this charge modification of Tm alters it's interactions within the thin filament to affect contraction. To date the modification of Tm resulting from cardiac stress and its effect on contraction are unknown. We propose three aims: I) To evaluate Tm-P in the stressed heart. Tm-P will be characterized in isolated perfused hearts treated with ischemia/reperfusion by phosphoprotein specific staining of 2-D gels and mass spectrometry. II) To determine the effect of Tm-P on binding to actin, troponin and to actin in the presence of troponin. Tm binding will be carried out by co-sedimentation and quantified on 2-D gels with densitometry. Ill) To determine the effect of Tm-P on the development of force in cardiac muscle. Calcium activated tension will be measured in skinned papillary bundles treated with gelsolin to selectively remove the thin filament and reconstituted with actin, troponin and non-phosphorylated or phosphorylated Tm. The knowledge gained from these experiments will provide novel insight into the regulatory mechanism of Tm-P and its effect on cardiac muscle contraction in health and disease.

描述（由申请人提供）：本研究中提出的实验调查了这样的假设：心脏中的原肌球蛋白磷酸化（Tm-P）会因心脏应激而改变，并且 Tm 的这种电荷修饰会改变其在细丝内的相互作用，从而影响收缩。迄今为止，心脏应激引起的 Tm 变化及其对收缩的影响尚不清楚。我们提出三个目标： I) 评估应激心脏中的 Tm-P。将通过 2-D 凝胶磷蛋白特异性染色和质谱法对经过缺血/再灌注处理的离体灌注心脏中的 Tm-P 进行表征。 II)确定Tm-P对与肌动蛋白、肌钙蛋白以及肌钙蛋白存在下的肌动蛋白结合的影响。 Tm 结合将通过共沉降进行，并通过密度测定法在 2-D 凝胶上进行定量。 III)确定Tm-P对心肌力量发展的影响。将在用凝溶胶蛋白处理的去皮乳头束中测量钙激活张力，以选择性地去除细丝并用肌动蛋白、肌钙蛋白和非磷酸化或磷酸化Tm重建。从这些实验中获得的知识将为 Tm-P 的调节机制及其对健康和疾病中心肌收缩的影响提供新的见解。