在G蛋白结合受体的激素选择性途径中对形状转换的计算映射
Supriyo Bhattacharya1, Nagarajan Vaidehi
1Division of Immunology, Beckman Research Institute of the City of Hope, 1500, East Duarte Road, Duarte, California 91010, USA.
Journal of the American Chemical Society
|March 19, 2010
概括
了解G蛋白结合受体 (GPCR) 激活途径是药物设计的关键. 计算方法揭示了连接体有效性如何影响受体构成和激活,为功能特定药物开发提供了洞察力.
科学领域:
- 计算生物物理学的计算生物物理.
- 结构生物学是结构生物学.
- 药理学 药理学 是一个学科.
背景情况:
- G蛋白结合受体 (GPCRs) 是重要的药物标.
- 连接物化学结构和有效性决定了GPCRs的活性状态构造.
- 了解激活通路对于设计功能特定的GPCR药物至关重要.
研究的目的:
- 为了研究不同的联体效能如何调节β2-上腺体受体的潜在能量格局.
- 通过计算推导和分析各种激动剂和部分激动剂的GPCRs激活途径.
- 探索特定分子相互作用 (如键和水极化) 在GPCR激活中的作用.
主要方法:
- 使用粗粒度计算方法,从β2-上腺素受体的晶体结构开始.
- 执行了受体跨膜螺旋体的系统形状跨度,随后进行了能量最小化和连接体重制.
- 采用蒙特卡洛算法来导出激活路径,与光谱测量验证.
主要成果:
- 衍生完全和部分激动剂的激活途径,与实验数据一致.
- 在完全激素激活过程中确定了关键事件:能量下坡阶段,中间形成和障碍穿越,涉及基5-基6键断裂.
- 由于固态阻碍,与全主动主动剂 (上腺素) 区分了部分主动剂 (萨尔布塔摩尔) 激活途径,并在虚拟查中证明了非甲基醇主动剂的丰富.
结论:
- 粗粒度计算方法可以有效地模拟GPCR激活路径和体特异性构造变化.
- 水的极化和螺旋间的键动态对于GPCR激活屏障的穿越至关重要.
- 开发的计算方法为生成实验假设和理解GPCR激活机制提供了强大的工具.
相关概念视频
G Protein-coupled Receptors
G Protein-Coupled Receptors or GPCRs are membrane-bound receptors that transiently associate with heterotrimeric G proteins and induce an appropriate response to sensory stimuli such as light, odors, hormones, cytokines, or neurotransmitters.
GPCRs are also called heptahelical, 7TM, or serpentine receptors, and consist of seven (H1-H7) transmembrane alpha-helices that span the bilayer to form a cylindrical core. The transmembrane helices are connected by three extracellular loops and three...
GPCRs are also called heptahelical, 7TM, or serpentine receptors, and consist of seven (H1-H7) transmembrane alpha-helices that span the bilayer to form a cylindrical core. The transmembrane helices are connected by three extracellular loops and three...
G Protein-coupled Receptors
G Protein-Coupled Receptors or GPCRs are membrane-bound receptors that transiently associate with heterotrimeric G proteins and induce an appropriate response to sensory stimuli such as light, odors, hormones, cytokines, or neurotransmitters.
GPCRs are also called heptahelical, 7TM, or serpentine receptors, and consist of seven (H1-H7) transmembrane alpha-helices that span the bilayer to form a cylindrical core. The transmembrane helices are connected by three extracellular loops and three...
GPCRs are also called heptahelical, 7TM, or serpentine receptors, and consist of seven (H1-H7) transmembrane alpha-helices that span the bilayer to form a cylindrical core. The transmembrane helices are connected by three extracellular loops and three...
Transducer Mechanism: G Protein–Coupled Receptors
G Protein–Coupled Receptors (GPCRs) are membrane-bound receptors that transiently associate with heterotrimeric G proteins and induce an appropriate response to various stimuli. GPCRs regulate critical physiological pathways and are excellent drug targets for treating diseases such as diabetes, cancer, obesity, depression, or Alzheimer's. Nearly 35% of approved drugs implement their therapeutic effects by selectively interacting with specific GPCRs.
GPCRs are also called heptahelical, 7TM, or...
GPCRs are also called heptahelical, 7TM, or...
G-protein Coupled Receptors
G-protein coupled receptors are ligand binding receptors that indirectly affect changes in the cell. The actual receptor is a single polypeptide that transverses the cell membrane seven times creating intracellular and extracellular loops. The extracellular loops create a ligand specific pocket which binds to neurotransmitters or hormones. The intracellular loops holds onto the G-protein.
G-protein Coupled Receptors
G-protein coupled receptors are ligand binding receptors that indirectly affect changes in the cell. The actual receptor is a single polypeptide that transverses the cell membrane seven times creating intracellular and extracellular loops. The extracellular loops create a ligand specific pocket which binds to neurotransmitters or hormones. The intracellular loops holds onto the G-protein.
Activation and Inactivation of G Proteins
Heterotrimeric G proteins are guanine nucleotide-binding proteins. As the name suggests, heterotrimeric G proteins are composed of three subunits: alpha, beta, and gamma. They remain GDP-bound or GTP-bound inside the cells and switch between inactive/active states. The Gα subunit possesses the nucleotide-binding pocket that binds guanine nucleotides and switches between GDP or GTP-bound states. In contrast, the Gꞵ and Gγ subunits are always bound together with high affinity and are together...


