Tropomyosin and tyrosine kinases in mechanics of cancer

原肌球蛋白和酪氨酸激酶在癌症机制中的作用

• 批准号: 9247873
• 负责人: MICHAEL Patrick SHEETZ
• 金额: $ 30.37万
• 依托单位: COLUMBIA UNIV NEW YORK MORNINGSIDE
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-05-01 至 2019-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9247873
• 关键词: Actin-Binding Protein; Actinin; Actins; Address; Adhesions; Adhesives; Affect; Apoptosis; Behavior; Binding; Binding Proteins; Caliber; Cell-Matrix Junction; Cells; Complex; Contractile Proteins; Cytoskeletal Proteins; Dependence; Development; EGF gene; Fibronectins; Fostering; Generations; Goals; Grant; Growth; Integrins; Link; Malignant Neoplasms; Measures; Mechanics; Microfilaments; Modification; Molecular; Molecular Weight; Muscle; Muscle Proteins; Myosin ATPase; Myosin Type II; Natural regeneration; Neoplasm Metastasis; Pathway interactions; Pattern; Phenotype; Phosphotransferases; Play; Process; Protein Tyrosine Kinase; Proteins; Psychological reinforcement; Recruitment Activity; Role; Sarcomeres; Signal Transduction; Site; Surface; Testing; Time; Tropomyosin; Vinculin; Work; alpha Actinin; cancer cell; cell growth; cell transformation; cell type; knock-down; mechanotransduction; nanofabrication; paxillin; polymerization; public health relevance; restoration; sensor; submicron; tropomodulin; tropomyosin kinase; tumor growth

DESCRIPTION (provided by applicant): The major goal of our lab is to understand the molecular pathways involved in rigidity and force sensing at cell-matrix adhesions. In this grant we will explore how these pathways are altered in cancers related to depletion of tropomyosin and modifications of tyrosine kinases. Cancer cells typically show anchorage independence of growth and the cytoskeletal protein, tropomyosin (Tm), is depleted in many cancers. Further, restoration of normal Tm1 expression reverses the transformed phenotype. Recently our lab has shown that cell rigidity sensing depends upon local contraction units that displace matrix by 50-70nm and if a threshold force is exceeded rapidly, then rigid adhesions form. Local contraction units resemble muscle sarcomeres in size (~2 �, function, and composition (actin, myosin II, alpha-actinin, tropomodulin and tropomyosin). After knockdown of Tm1, the local contractions are dramatically altered and the cells no longer sense the rigidity of fibronectin-coated substrates. Similarly, the knockdown of tyrosine kinases alters both rigidity sensing and the pattern of contractions that are measured from displacements of 500nm diameter PDMS pillars. We propose now to follow the time course of force dependence and the concentration and dissipation of adhesion and contractile proteins at the pillars. This will tell us the order of binding and provide clues about the molecular steps involved in the cycles of contraction and release. We will then address the question of how the tyrosine kinases involved in rigidity sensing (AXL, ROR2 and EGF) interplay with the early adhesion complexes as a function of the force on the complexes. Since tropomyosin inhibits transformation and tumor growth, we will determine how tropomyosin depletion alters the pattern of adhesion maturation on soft surfaces that enables transformation. Thus, we will be able to better understand the mechanochemical basis of transformation.

描述（由申请人提供）：我们实验室的主要目标是了解细胞基质粘附的刚性和力传感所涉及的分子途径。在这笔资助中，我们将探索这些途径在与原肌球蛋白消耗和酪氨酸激酶修饰相关的癌症中如何改变。癌细胞通常表现出生长的锚定独立性，并且细胞骨架蛋白原肌球蛋白 (Tm) 在许多癌症中被耗尽。此外，恢复正常的 Tm1 表达会逆转转化的表型。最近我们的实验室表明，细胞刚性传感取决于局部收缩单元，该收缩单元使基质位移 50-70nm，如果快速超过阈值力，则会形成刚性粘附。局部收缩单位在大小（~2°、功能和组成（肌动蛋白、肌球蛋白 II、α-肌动蛋白、原调蛋白和原肌球蛋白）上类似于肌肉肌节。Tm1 敲低后，局部收缩发生显着改变，细胞不再感知纤连蛋白包被的基质的刚性。同样，酪氨酸激酶的敲低会改变刚性感应 以及根据 500 nm 直径 PDMS 柱的位移测量的收缩模式。我们现在建议跟踪力依赖性的时间过程以及支柱上粘附和收缩蛋白的浓度和消散。这将告诉我们的顺序 结合并提供有关收缩和释放循环中涉及的分子步骤的线索。然后，我们将解决参与刚性感应的酪氨酸激酶（AXL、ROR2 和 EGF）如何与早期粘附复合物相互作用的问题，作为复合物上的力的函数。由于原肌球蛋白抑制转化和肿瘤生长，我们将确定原肌球蛋白消耗如何改变软表面上的粘附成熟模式，从而实现转化。因此，我们将能够更好地理解转化的机械化学基础。