植物G蛋白调节机制的结构功能分析确定了关键的Gα-RGS蛋白相互作用
Maria Daniela Torres-Rodriguez1, Soon Goo Lee2, Swarup Roy Choudhury3
1Donald Danforth Plant Science Center, St Louis, Missouri, USA.
The Journal of biological chemistry
|April 3, 2024
概括
植物G蛋白α子单元 (Gα) 和它们的调节器 (RGS) 对于信号传递至关重要. 结构分析揭示了多种植物之间保存的Gα:RGS相互作用,挑战了适应性共同进化理论.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 生物化学 生物化学
背景情况:
- 异构三聚体GTP结合蛋白α子单元 (Gα) 和G蛋白信号调节器 (RGS) 蛋白质是真核生物中的关键信号转换器.
- 虽然Gα和RGS机制得到保护,但由于选择性压力低,RGS基因在植物中经常丢失.
- 阿拉比多普西斯Gα (AtGPA1) 已经为我们的理解提供了信息,但需要超越这个模型的研究.
研究的目的:
- 为了研究超越Arabidopsis.植物Gα:RGS相互作用的结构基础和调节机制.
- 为了比较具有和没有RGS蛋白质的物种中的Gα结构和动态.
- 评估植物Gα和RGS蛋白之间的适应性共进化的假设.
主要方法:
- 使用X射线晶体学来确定Oryza sativa Gα (没有RGS) 和 Selaginella moellendorffi Gα (有RGS) 的结构.
- 用分子动力学模拟来分析Gα-RGS相互作用并确定关键的接触残留物.
- 结构和动态特征在不同的植物Gα蛋白和甲状动物对应物之间进行了比较.
主要成果:
- 植物Gα蛋白的三维结构,RGS相互作用能力和动态特征被保留,并且与AtGPA1和甲基动物Gα相似.
- 分子动力学模拟确定了关键Gα-RGS相互作用的交换区域中的特定残留接触.
- 由于特定的氨基酸替代,没有观察到Gα-RGS相互作用动态的显著差异.
结论:
- 植物Gα蛋白在各种物种中表现出保存的结构和动态特性,包括与RGS蛋白的相互作用.
- 这些发现为植物G蛋白的调节机制提供了宝贵的见解.
- 数据不支持植物Gα和RGS蛋白之间的适应性共进化的假设.
相关概念视频
Activation and Inactivation of G Proteins
7.1K
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...
7.1K
Assembly of Signaling Complexes
5.8K
Multiprotein signaling complexes are formed in a dynamic process involving protein-protein interactions at the cytoplasmic domain of transmembrane receptors or enzymatic and non-enzymatic proteins associated with the receptor. These complexes ensure the activation and propagation of intracellular signals that regulate cell functions.
Interaction domains in cell signaling
Interaction domains recognize exposed features of their binding partners containing post-translationally modified sequences,...
Interaction domains in cell signaling
Interaction domains recognize exposed features of their binding partners containing post-translationally modified sequences,...
5.8K
Cell Signaling in Plants
5.6K
Plant cells communicate to coordinate their cycle of growth, flowering and fruiting, and activities in roots, shoots, and leaves in response to the changing environmental conditions. Plant signaling is distinct from animal signaling. Plants primarily utilize enzyme-linked receptors, whereas the largest class of cell-surface receptors in animals are G-protein coupled receptors (GPCRs). Unlike animals, receptor tyrosine kinases are rare in plants. Instead, plants have a diverse class of...
5.6K
GTPases and their Regulation
8.4K
Guanine nucleotide-binding proteins (G-proteins), also known as GTPases, are a superfamily of proteins that regulate many cellular processes, such as cell signaling, vesicular transport, and the regulation of cell shape and motility. Mutation or dysfunction of these proteins can lead to disease. There are around 40,000 known G-proteins that can broadly be classified into two groups ‒ small G-proteins consisting of a single domain and large multi-domain G-proteins.
Large G-proteins,...
Large G-proteins,...
8.4K
G Protein-coupled Receptors
11.9K
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...
11.9K
Transducer Mechanism: G Protein–Coupled Receptors
2.0K
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,...
GPCRs are also called heptahelical,...
2.0K


