Functional roles of lipids in early B cell receptor signaling.

脂质在早期 B 细胞受体信号传导中的功能作用。

• 批准号: 9058146
• 负责人: Sarah L Veatch
• 金额: $ 28.83万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-01 至 2019-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9058146
• 关键词: Adaptor Signaling Protein; Antigens; Apoptosis; Autoimmunity; B-Lymphocytes; Behavior; Biochemical; Biochemical Genetics; Biological; Biological Process; Cell Communication; Cell Line; Cell Proliferation; Cell Survival; Cell membrane; Cell physiology; Cells; Color; Cytokinesis; Data; Defect; Development; Disease; Down-Regulation; Environment; Equilibrium; Goals; Health; Heterogeneity; Human; Image; Imaging Techniques; Immune; Immune System Diseases; Immune response; Immunologic Deficiency Syndromes; Interphase Cell; Intervention; Knowledge; Laboratories; Lead; Length; Ligand Binding; Link; Lipids; Lymphocyte; Lymphoma; Measures; Mediating; Mediator of activation protein; Membrane; Membrane Lipids; Membrane Proteins; Methodology; Methods; Mission; Modeling; Monitor; Normal Cell; Peptides; Phase; Phosphoric Monoester Hydrolases; Phosphotransferases; Physiological; Play; Process; Property; Proteins; Receptor Activation; Receptor Cell; Receptor Signaling; Receptors, Antigen, B-Cell; Recruitment Activity; Regulation; Research; Resolution; Role; Signal Pathway; Signal Transduction; Site; Staging; Stream; Testing; Vesicle; Work; base; cell type; cold temperature; crosslink; effective intervention; human disease; innovation; insight; membrane model; novel; physical property; predictive modeling; prevent; protein function; protein protein interaction; receptor; research study; signal processing; stem; tool; treatment strategy

DESCRIPTION (provided by applicant): The physical properties of plasma membrane lipids play vital roles in B cell receptor (BCR) activation, yet remarkably little is known regarding how lipids regulate the organization and activity of proteins within this signaling pathway. Overcoming this basic knowledge gap is necessary to elucidate the mechanisms underlying this essential biological function and will lead to the development of novel interventions for immune- related diseases. The experiments outlined in this proposal will identify the role plasma membrane lipids in regulating interactions between the BCR and down-stream mediators of the immune response, and will develop experimental methods to modulate lipid-mediated interactions in cells. The working hypothesis is that healthy B cells exploit heterogeneity maintained by a critical composition of its membrane lipids, to balance interactions between the BCR, activating kinases, and down-regulating phosphatases in order to facilitate early activation steps and suppress receptor activity in resting cells. The proposed research tests this working hypothesis by quantifying lipid-mediated interactions between the BCR and plasma membrane proteins in normal B cells and in cells treated with targeted perturbations of lipid heterogeneity. Guided by extensive preliminary data, two specific aims will be pursued: 1) Quantify and modulate effective interactions between the BCR and minimal membrane anchors and 2) Identify the roles of lipids in early B cell receptor activation. Both aims will utilize a new and tested method developed in the applicant's laboratory to directly measure interaction potentials between plasma membrane proteins using super-resolution imaging techniques. Both aims will also apply a novel class of membrane perturbations shown to modify the phase behavior of isolated plasma membrane vesicles and the composition of cross-linked BCR receptor clusters in cells. In the first aim, interaction energies will be measured between the BCR and membrane protein anchor motifs expressed in B cells and interactions will be modulated with biochemical perturbations. Under the second aim, the activity of full length proteins involved in BCR signaling will be measured and their effective interactions with other signaling components will be quantified over a range of experimental conditions. A predictive model will be developed that includes protein and lipid interactions, and plasma membrane heterogeneity will be investigated in lymphoma cells with known defects in BCR signaling. Although the proposed research will take place in B cells, it has implications for studying of role of lipids in other biological proceses and cell types. This approach is innovative because it draws on cutting edge experimental methodologies as well as the unique perspective that lipids impact functional processes by modulating effective interactions between embedded proteins. The proposed work is significant because it will establish a mechanism for lipid-mediated control of immune signaling processes enabling new strategies for the treatment of immune related disease through manipulation of plasma membrane physical properties.

描述（由申请人提供）：质膜脂质的物理特性在B细胞受体（BCR）激活中起着至关重要的作用，但对于脂质如何调节该信号传导途径中蛋白质的组织和活动知之甚少。克服这一基本知识差距对于阐明这种基本生物学功能的基础机制是必要的，并将导致对免疫相关疾病的新干预措施的发展。该提案中概述的实验将确定质膜脂质在调节免疫反应的BCR和下游介质之间的相互作用中的作用，并将开发实验方法来调节细胞中脂质介导的相互作用。有效的假设是，健康的B细胞利用其膜脂质的临界组成维持的异质性，以平衡BCR之间的相互作用，激活激酶和下调磷酸酶，以促进早期激活步骤并抑制静息细胞中受体活性。提出的研究通过量化正常B细胞​​中BCR和质膜蛋白之间的脂质介导的相互作用以及用脂质异质性靶向扰动处理的细胞中来检验该假设。 在广泛的初步数据的指导下，将追求两个具体目标：1）量化和调节BCR和最小膜锚之间的有效相互作用，2）确定脂质在早期B细胞受体激活中的作用。这两个目标都将利用申请人实验室中开发的一种新的和经过测试的方法，以使用超分辨率成像技术直接测量质膜蛋白之间的相互作用电位。这两个目标还将应用一类新型的膜扰动，以改变分离的质膜囊泡的相行为以及细胞中交联的BCR受体簇的组成。在第一个目标中，将在B细胞中表达的BCR和膜蛋白锚定基序之间测量相互作用能，并通过生化扰动调节相互作用。在第二个目标下，将测量参与BCR信号的全长蛋白的活性，并在一系列实验条件下量化它们与其他信号成分的有效相互作用。将开发一个包括蛋白质和脂质相互作用的预测模型，并将在BCR信号传导中具有已知缺陷的淋巴瘤细胞中研究质膜异质性。尽管拟议的研究将在B细胞中进行，但它对研究脂质在其他生物学过程和细胞类型中的作用具有影响。这种方法具有创新性，因为它借鉴了尖端实验方法，以及脂质通过调节嵌入式蛋白质之间有效相互作用来影响功能过程的独特观点。提出的工作很重要，因为它将建立一种脂质介导的免疫信号传导过程控制的机制，从而通过操纵质膜物理性质来治疗免疫相关疾病的新策略。