Structural basis of antagonism within the TGFbeta-superfamily

TGFβ超家族内拮抗作用的结构基础

• 批准号: 7596215
• 负责人: THOMAS B THOMPSON
• 金额: $ 31.39万
• 依托单位: UNIVERSITY OF CINCINNATI
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-04-01 至 2013-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7596215
• 关键词: Activins; Affect; Binding; Biological; Biological Assay; Biological Process; Biology; Cleaved cell; Collaborations; Collection; Complex; Coupled; Data; Development; Disease; Engineering; Etiology; Event; Family; Fibrosis; Follistatin; Goals; Growth; Human; Immunologic Surveillance; Individual; Kinetics; Knowledge; Laboratories; Life; Ligand Binding; Ligands; Luciferases; Malignant Neoplasms; Mediating; Molecular; Muscle; Muscular Dystrophies; Mutagenesis; N-terminal; Neoplasms; Property; Publishing; Regulation; Reporter; Reproduction; Research; Research Personnel; Resolution; Resources; Roentgen Rays; Role; Signal Transduction; Signaling Molecule; Site-Directed Mutagenesis; Solutions; Specificity; Staging; Structure; Subgroup; Surface; Surface Plasmon Resonance; Testing; Time; Tissues; Transforming Growth Factor beta; Wasting Syndrome; Work; base; biological systems; cell growth; cell motility; chordin; design; extracellular; falls; human disease; mutant; myostatin; organ regeneration; planetary Atmosphere; programs; public health relevance; receptor; research study; stem cell differentiation; stem cell fate; success; therapy design; wasting

DESCRIPTION (provided by applicant): Approximately 40 unique secreted ligands, divided into three subgroups (TGF¿s, activins and BMPs) form the TGF¿-superfamily whose function is to coordinate numerous cellular events. TGF¿-family ligands are already being targeted therapeutically by blocking their interactions with receptors to alleviate human disorders such as cancer, fibrosis and muscle wasting disease. Naturally, ligands are regulated by either formation of an inactive covalent complex with their N-terminal propeptide that is cleaved during synthesis or by neutralization by one of a number of structurally-diverse extracellular antagonists. Binding of these molecules to ligands can range from very broad, where multiple ligands are antagonized by a single antagonist or very specific where one antagonist only recognizes a distinct ligand. While TGF¿-family ligands are structurally similar, the molecular basis of how structurally-diverse antagonists selectively neutralize subsets of ligands remains unclear. Therefore, our long-term goal of this application is to elucidate mechanisms of specificity among the TGF¿-family antagonists. This proposal will focus on the divergent ligand specificity among three activin-family antagonists: Follistatin (FST) (broad ligand specificity), Follistatin-like 3 (FSTL3) (moderate specificity), and propeptides (exquisite specificity). Our central hypothesis is that antagonists differentially interact with conserved and nonconserved ligand surfaces to confer a range of specificity within the activin-family of ligands. In Aim 1, we will determine how FST antagonists confer broad ligand antagonism through a combination of X-ray structure analysis of FST:ligand complexes and binding studies. In Aim 2, we will determine how FSTL3 domain differences restrict binding to a few ligands, and in Aim 3, we will establish how the propeptide forms an inactive complex with the myostatin ligand. In all three aims, we will combine X-ray structure determination with competition and surface plasmon resonance binding experiments along with cellular-based assays to elucidate mechanisms of specificity for each antagonist. Elucidating details of the mechanisms that neutralize TGF¿-family ligands will help in development of new strategies and optimize current therapies aimed at antagonizing ligands. PUBLIC HEALTH RELEVANCE Presently, TGF¿-family ligands are being neutralized therapeutically to alleviate human disorders such as cancer, fibrosis and muscle wasting. Our research is significant as it is expected to provide details of binding molecules that antagonize ligands. This information will strengthen efforts to customize therapies designed to neutralize TGF¿-family ligands.

描述（由申请人提供）：大约40种独特的分泌配体，分为三个亚组（TGF β、激活素和BMP），形成TGF β超家族，其功能是协调许多细胞事件。转化生长因子- 家族配体已经通过阻断它们与受体的相互作用而被治疗靶向，以减轻人类疾病，如癌症、纤维化和肌肉萎缩病。天然地，配体通过与其在合成期间裂解的N-末端前肽形成无活性的共价复合物或通过被许多结构多样的细胞外拮抗剂之一中和来调节。这些分子与配体的结合可以是非常广泛的，其中多种配体被单一拮抗剂拮抗，或者是非常特异的，其中一种拮抗剂仅识别不同的配体。虽然TGF？- 家族配体在结构上相似，结构多样性拮抗剂如何选择性中和配体亚群的分子基础仍不清楚。因此，本申请的长期目标是阐明TGF β家族拮抗剂之间的特异性机制。该提案将重点关注三种激活素家族拮抗剂之间不同的配体特异性：卵泡抑制素（FST）（广泛的配体特异性）、卵泡抑制素样3（FSTL 3）（中度特异性）和前肽（精致的特异性）。我们的中心假设是，拮抗剂与保守和非保守的配体表面差异相互作用，赋予一系列的特异性激活素家族的配体。在目的1中，我们将确定如何FST拮抗剂赋予广泛的配体拮抗作用，通过结合X射线结构分析FST：配体复合物和结合研究。在目标2中，我们将确定FSTL 3结构域差异如何限制与几个配体的结合，在目标3中，我们将确定前肽如何与肌肉生长抑制素配体形成无活性复合物。在所有这三个目标，我们将结合联合收割机X射线结构测定与竞争和表面等离子体共振结合实验沿着与细胞为基础的测定，以阐明每种拮抗剂的特异性机制。阐明中和TGF β-家族配体的机制的细节将有助于开发新的策略和优化旨在拮抗配体的当前疗法。目前，TGF β-家族配体正在治疗上被中和以减轻人类疾病，如癌症、纤维化和肌肉萎缩。我们的研究是有意义的，因为它有望提供拮抗配体的结合分子的细节。这些信息将加强定制旨在中和TGF ²家族配体的疗法的努力。