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: 8245799
• 负责人: THOMAS B THOMPSON
• 金额: $ 30.59万
• 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 2014-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8245799
• 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; Health; 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; 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; receptor; research study; stem cell differentiation; stem cell fate; success; therapy design; tissue regeneration; 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，分为三个亚群（TGF¿s，激活素和bmp），构成TGF¿-超家族，其功能是协调许多细胞事件。TGF -家族配体已经成为治疗的目标，通过阻断它们与受体的相互作用来缓解人类疾病，如癌症、纤维化和肌肉萎缩疾病。自然地，配体通过与n端前肽形成非活性共价复合物（在合成过程中被切割）或通过多种结构多样的细胞外拮抗剂中的一种进行中和来调节。这些分子与配体的结合范围可以非常广泛，其中多个配体被单一拮抗剂拮抗，或者非常特异性，其中一个拮抗剂只识别一个独特的配体。虽然TGF¿-家族配体在结构上相似，但结构多样的拮抗剂如何选择性中和配体亚群的分子基础尚不清楚。因此，我们的长期目标是阐明TGF¿-家族拮抗剂的特异性机制。本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listatin (FST)（广泛配体特异性），卵泡listatin样3 (FSTL3)（中等特异性）和前肽（精致特异性）。我们的中心假设是拮抗剂与保守和非保守配体表面的不同相互作用，以赋予激活素家族配体的一系列特异性。在Aim 1中，我们将通过结合FST：配体复合物的x射线结构分析和结合研究来确定FST拮抗剂如何赋予广泛的配体拮抗剂。在Aim 2中，我们将确定FSTL3结构域的差异如何限制与少数配体的结合，而在Aim 3中，我们将确定前肽如何与肌肉生长抑制素配体形成非活性复合物。在这三个目标中，我们将结合x射线结构测定与竞争和表面等离子体共振结合实验以及基于细胞的分析来阐明每种拮抗剂的特异性机制。阐明中和TGF¿-家族配体的机制细节将有助于开发新的策略，并优化目前针对拮抗配体的治疗方法。目前，TGF¿-家族配体正被用于治疗性地缓解人类疾病，如癌症、纤维化和肌肉萎缩。我们的研究具有重要意义，因为它有望提供拮抗配体的结合分子的细节。这一信息将加强定制疗法的努力，旨在中和TGF¿-家族配体。

项目成果

Myostatin stimulates, not inihibits, C2C12 myoblast proliferation.

• DOI: 10.1210/en.2013-2107
• 发表时间: 2014-01
• 期刊: Endocrinology
• 影响因子: 4.8
• 作者: B. D. Rodgers;Benjamin D. Wiedeback;K. Hoversten;Melissa F. Jackson;R. G. Walker;T. Thompson