Structural insights into the unique activation mechanisms of receptor tyrosine kinases

受体酪氨酸激酶独特激活机制的结构见解

基本信息

批准号：
10600031
负责人：
Xiaochen Bai
金额：
$ 40.63万
依托单位：
UT SOUTHWESTERN MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-07-01 至 2025-04-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10600031
关键词：
Affect Agonist Agrin Binding Biochemical Biological Assay Biological Process Cell Surface Receptors Cell membrane Cell physiology Cell surface Cells Complex Cryoelectron Microscopy Cytoplasm Data Development Dimerization Environment Exhibits Family Goals HGF gene Heparin In Vitro Inflammation KDR gene Laboratories Learning Length Ligand Binding Ligands Link Lipids Liposomes Maintenance Malignant Neoplasms Membrane Membrane Lipids Modeling Molecular Molecular Conformation Muscle Muscle Cells Mutagenesis Neuromuscular Junction Normal Cell PDGFRB gene Phosphatidylserines Phosphorylation Phosphotransferases Physiological Play Protein Isoforms Proteins Protomer Receptor Activation Receptor Protein-Tyrosine Kinases Regulation Resolution Role Sampling Signal Transduction Structure TAC1 gene Tertiary Protein Structure adaptive immunity antagonist cell motility crosslink dimer extracellular human disease improved insight member nanodisk receptor reconstitution recruit

项目摘要

Receptor tyrosine kinases (RTKs) play key roles in regulating normal cellular processes and are linked to many human diseases. Each RTK protomer contains an extracellular region that binds activating ligands, a single transmembrane helix, and an intracellular region that contains the kinase domain necessary for intracellular signaling. For many RTKs, their cognate ligands form stable homodimers, and the binding of dimeric ligand to the extracellular region of RTK drives receptor dimerization, which then brings two intracellular kinases in close proximity, enabling their autophosphorylation. The phosphorylated kinases can further recruit effector proteins, and thereby triggering downstream signaling cascade. This “ligand-induced-dimerization” is the long-standing model for the activation of RTKs, and has been well characterized by extensive structural and functional studies. Nevertheless, it has been suggested that several members in RTK family use unique activation mechanisms. For instance, the MuSK receptor alone cannot directly bind to and be activated by its ligand Agrin, but requiring assistance of the co-receptor Lrp4 on the muscle cell surface for activation. In addition, the activation of TAM receptor requires not only the binding of its ligands, but also the involvement of phosphatidylserine lipid (PtdSer) from plasma membrane. Furthermore, our preliminary structure results showed that, different to all other RTKs, one HGF molecular can simultaneously engages two c-MET receptors by utilizing two distinct interfaces; therefore, a single HGF is sufficient for the activation of c-MET receptor, which represents another paradigm in activation mechanisms of RTK. The goal of this project is to study the structures and functions of several special RTKs, including MuSK, TAM and c-MET receptors, whose activation mechanism are still poorly understood. Solving the high-resolution structures of different unique members of RTK family in the ligand-bound active state will explain the specific features that differentiate these receptors from other RTKs, and reveal the common mechanism and diversification in the activation of RTK. Aim 1 will be focused on the functional and structural analyses of MuSK receptor complex. This study will reveal the detailed binding mode between MuSK, Lrp4 and Agrin, and explain why co-receptor Lrp4 is critical for the activation of MuSK. Aim 2 will be focused on biochemical and structural analyses of TAM receptor in the membrane associated functional state. The result from this study will allow us to explain the functional importance of PtdSer in TAM activation. Aim 3 will be focused on the structural determination of c-MET receptor in the HGF bound active state to understand why single HGF molecular is sufficient for c-MET activation.

受体酪氨酸激酶 (RTK) 在调节正常细胞过程中发挥关键作用，并与许多细胞相关每个 RTK 原体都包含一个结合激活配体的细胞外区域，即单个区域。跨膜螺旋，以及包含细胞内必需的激酶结构域的细胞内区域对于许多 RTK，它们的同源配体形成稳定的同二聚体，并且二聚配体与 RTK 的胞外区域驱动受体二聚化，然后使两个胞内激酶靠近接近，使它们能够进行自身磷酸化，磷酸化激酶可以进一步招募效应蛋白，并触发下游信号级联反应，这种“配体诱导二聚化”是长期存在的。 RTK 激活模型，并已通过广泛的结构和功能得到了很好的表征然而，研究表明 RTK 家族中的几个成员使用独特的激活。例如，MuSK 受体本身不能直接与其配体结合并被其激活。 Agrin，但需要肌肉细胞表面的辅助受体 Lrp4 的帮助才能激活。 TAM受体的激活不仅需要其配体的结合，还需要来自质膜的磷脂酰丝氨酸脂质（PtdSer）此外，我们的初步结构结果。研究表明，与所有其他 RTK 不同，一个 HGF 分子可以同时接合两个 c-MET 受体通过利用两个不同的界面；因此，单个 HGF 足以激活 c-MET 受体，它代表了 RTK 激活机制的另一个范例。该项目的目标是研究 RTK 的激活机制。几种特殊RTK的结构和功能，包括MuSK、TAM和c-MET受体，其激活机制仍然知之甚少，无法解决不同独特的高分辨率结构。处于配体结合活性状态的 RTK 家族成员将解释区分这些成员的具体特征来自其他 RTK 的受体，并揭示 RTK 激活的共同机制和多样性。目标 1 将重点关注 MuSK 受体复合物的功能和结构分析。揭示 MuSK、Lrp4 和 Agrin 之间的详细结合模式，并解释为什么辅助受体 Lrp4 至关重要用于激活 MuSK 的 Aim 2 将重点关注 TAM 受体的生化和结构分析。这项研究的结果将使我们能够解释功能状态。 PtdSer 在 TAM 激活中的重要性目标 3 将集中于 c-MET 的结构测定。处于 HGF 结合活性状态的受体，以了解为什么单个 HGF 分子足以用于 c-MET 激活。

项目成果

期刊论文数量（5）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Oncogenic RAS Drives Resistance to Pemigatinib in Cholangiocarcinoma Harboring a FGFR2 Delins Disrupting Ligand Binding.

致癌 RAS 驱动含有 FGFR2 Delins 的胆管癌对 Pemigatinib 产生耐药性，破坏配体结合。

DOI：
10.1200/po.22.00340
发表时间：
2023
期刊：
JCO precision oncology
影响因子：
4.6
作者：
Lim,Mir;Lynch,PatrickT;Bai,Xiaochen;Hsiehchen,David
通讯作者：
Hsiehchen,David

A structural model of a Ras-Raf signalosome.

DOI：
10.1038/s41594-021-00667-6
发表时间：
2021-10
期刊：
Nature structural & molecular biology
影响因子：
16.8
作者：
Mysore VP;Zhou ZW;Ambrogio C;Li L;Kapp JN;Lu C;Wang Q;Tucker MR;Okoro JJ;Nagy-Davidescu G;Bai X;Plückthun A;Jänne PA;Westover KD;Shan Y;Shaw DE
通讯作者：
Shaw DE