Transducing Hedgehog signals across the plasma membrane

跨质膜转导 Hedgehog 信号

基本信息

批准号：
10642913
负责人：
ADRIAN SALIC
金额：
$ 42.38万
依托单位：
HARVARD MEDICAL SCHOOL
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-09-01 至 2025-05-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10642913
关键词：
Adopted Affinity Chromatography Binding Biochemical Biochemistry Biological Biological Assay Cancer Etiology Cell Maintenance Cell membrane Cells Cellular biology Chemicals Cholesterol Congenital Abnormality Cryoelectron Microscopy Cytoplasm Development Embryonic Development Ensure Erinaceidae Event Extracellular Domain Fatty Acids G-Protein-Coupled Receptors Health Heterotrimeric GTP-Binding Proteins Human Hyperactivity Interphase Cell Label Ligands Lipids Malignant Neoplasms Maps Mass Spectrum Analysis Membrane Membrane Proteins Modeling Molecular Molecular Conformation Mutagenesis Mutation Oncogenic Oncoproteins Palmitates Pathogenesis Pathway interactions Process Proteins Roentgen Rays Role SHH gene Signal Pathway Signal Transduction Sterols Structure Testing Transmembrane Domain Tumor Suppressor Proteins Work X-Ray Crystallography adult stem cell analog cancer therapy cancer type experimental study hedgehog signal transduction intercellular communication mutant nanodisk novel patched protein reconstitution smoothened signaling pathway structural biology tool transmission process

项目摘要

Project summary The Hedgehog (Hh) signaling pathway is essential for embryogenesis, for adult stem cell maintenance, and is involved in birth defects and cancer. In the absence of stimulation, the tumor suppressor membrane protein, Patched1 (Ptch1), inhibits the seven-spanner oncoprotein Smoothened (Smo), thus inhibiting Hh signaling. The pathway is activated by the Sonic Hedgehog ligand (Shh), which binds and inhibits Ptch1, allowing Smo to become active and to trigger downstream signaling events. In spite of the critical importance of Ptch1 and Smo, their molecular mechanisms remain obscure: it is unknown how Ptch1 inhibits Smo, how the Shh inhibits Ptch1, how Smo is activated, and how it relays signals downstream. We recently discovered that cholesterol is the long-sought endogenous Smo activator, and that Ptch1 controls Smo via cholesterol. We solved X-ray structures of active Smo, which suggested a mechanism for activation by cholesterol. The structures also explained the hyperactivity of a classical oncogenic Smo mutant and pointed to a portion in Smo likely involved in downstream signaling. In preliminary work, we discovered rapid cholesterol transfer from Smo to Ptch1, suggesting a novel mechanism for Smo inhibition by Ptch1. This cholesterol transfer is blocked by Shh, via the novel palmitate-dependent interaction between Shh and Ptch1, which we previously discovered, suggesting a simple mechanism for Hh pathway activation. We propose to use biochemistry, chemical, cell and structural biology to accomplish the following aims: A) To determine how the Ptch1 inhibits Smo, and how the Hh ligand inhibits Ptch1, to trigger Hh signaling B) To determine precisely how cholesterol activates Smo C) To elucidate how Smo relays Hh signals to the cytoplasm These studies are important for the following reasons: 1) They will advance our understanding of the Hh pathway, by deciphering critical signaling mechanisms; 2) They will clarify how Smo and Ptch1 mutations cause cancer; 3) They will identify novel targets for blocking oncogenic Hh signaling, based on the mechanisms of Smo and Ptch1; and 4) The novel lipid probes that we developed for studying Shh and Ptch1 will be broadly applicable beyond the Hh pathway.

项目概要 Hedgehog (Hh) 信号通路对于胚胎发生、成体干细胞维持、并与出生缺陷和癌症有关。在没有刺激的情况下，抑癌膜蛋白质 Patched1 (Ptch1) 抑制七跨癌蛋白 Smoothened (Smo)，从而抑制 Hh 发信号。该通路由 Sonic Hedgehog 配体 (Shh) 激活，该配体结合并抑制 Ptch1，允许 Smo 变得活跃并触发下游信号事件。尽管至关重要 Ptch1 和 Smo 的作用，其分子机制仍不清楚：尚不清楚 Ptch1 如何抑制 Smo，如何抑制 Smo Shh 抑制 Ptch1、Smo 如何激活以及它如何向下游传递信号。我们最近发现胆固醇是人们长期寻找的内源性 Smo 激活剂，而 Ptch1 通过胆固醇控制 Smo。我们解决了活性 Smo 的 X 射线结构，这提出了一种机制胆固醇的激活。这些结构还解释了经典致癌 Smo 突变体的过度活跃并指出 Smo 中的一部分可能涉及下游信号传导。在前期工作中，我们发现胆固醇从 Smo 快速转移到 Ptch1，表明 Ptch1 抑制 Smo 的新机制。这通过 Shh 和 Ptch1 之间新型的棕榈酸依赖性相互作用，Shh 可以阻断胆固醇转移，我们之前发现了这一点，提示了 Hh 通路激活的简单机制。我们建议利用生物化学、化学、细胞和结构生物学来实现以下目标： A) 确定 Ptch1 如何抑制 Smo，以及 Hh 配体如何抑制 Ptch1，以触发 Hh 信号传导 B) 精确确定胆固醇如何激活 Smo C) 阐明 Smo 如何将 Hh 信号传递到细胞质这些研究很重要，原因如下：1）它们将增进我们对 Hh 通路，通过破译关键信号机制； 2) 他们将阐明 Smo 和 Ptch1 突变是如何发生的导致癌症； 3) 他们将根据 Smo和Ptch1的机制； 4）我们为研究Shh和Ptch1而开发的新型脂质探针将广泛适用于 Hh 途径之外。

项目成果

期刊论文数量（7）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Structural insights into proteolytic activation of the human Dispatched1 transporter for Hedgehog morphogen release.

DOI：
10.1038/s41467-021-27257-w
发表时间：
2021-11-29
期刊：
Nature communications
影响因子：
16.6
作者：
Li W;Wang L;Wierbowski BM;Lu M;Dong F;Liu W;Li S;Wang P;Salic A;Gong X
通讯作者：
Gong X

Mechanism and ultrasensitivity in Hedgehog signaling revealed by Patched1 disease mutations.

Patched1 疾病突变揭示的 Hedgehog 信号传导机制和超敏感性。

DOI：
10.1073/pnas.2006800118
发表时间：
2021
期刊：
Proceedings of the National Academy of Sciences of the United States of America
影响因子：
11.1
作者：
Petrov,Kostadin;deAlmeidaMagalhaes,Taciani;Salic,Adrian
通讯作者：
Salic,Adrian

Hedgehog Pathway Activation Requires Coreceptor-Catalyzed, Lipid-Dependent Relay of the Sonic Hedgehog Ligand.