杂体G蛋白和单体G蛋白之间有什么区别|比较类似术语之间的差异

这关键区别在异源G蛋白和单体G蛋白之间是否是杂体G蛋白是由α（α），β（β）和伽马（γ）亚基组成的大膜相关G蛋白，而单体G蛋白是仅由膜相关的G蛋白，仅由一个由A组成的G蛋白仅由A组成α亚基。

G蛋白（鸟嘌呤核苷酸结合蛋白）是一种蛋白质家族，充当细胞内部分子开关。他们参与从细胞外部的各种刺激到内部传输信号。G蛋白可以分为两个不同的蛋白质家族：异源G蛋白和单体G蛋白。杂体G蛋白是一种大蛋白，而单体G蛋白是一种小蛋白。

1。概述和关键差异
2。什么是异类G蛋白
3。什么是单体G蛋白
4。相似性 - 杂体G蛋白和单体G蛋白
5。杂体G蛋白与单体G蛋白的表格形式
6.Summary – Heteromeric G Protein vs Monomeric G Protein

什么是异类G蛋白?

杂体G蛋白是由α（α），β（β）和γ（γ）亚基组成的大G蛋白。杂体G蛋白形成异三聚体复合物。异三聚体和单体G蛋白之间最大的非结构差异是异三聚体G蛋白与其结合cell surface receptor(G protein-coupled receptors) directly. The alpha subunit of heteromeric G protein is usually attached to either aGTPor GDP that serves as an on or off switch for the activation of G protein.

Figure 01: Heteromeric G Protein

当配体与A结合时GPCR，GPCR获取GEF（鸟嘌呤核苷酸交换因子）能力。这通过将α亚基上的GDP交换为GTP来激活G蛋白。GTP与α亚基的结合导致α亚基与G蛋白的其余部分的结构变化和解离。通常，α亚基结合了下游信号级联的膜结合效应子蛋白。Beta-Gamma综合体也可以执行此功能。此外，杂体G蛋白还参与了CAMP/PKA途径，离子通道，MAPK和PI3K等途径。

什么是单体G蛋白？

Monomeric G protein is a small membrane-associated G protein that is made up of only an alpha subunit. The small monomeric G protein is homologous to the alpha subunit of the large heteromeric G protein. This family of small GTPases includes the RAS superfamily, which is further split into subfamilies based on structural, sequence, and functional similarities. Moreover, each subfamily of small GTPases plays a slightly different role vital in the regulation of intracellular signalling pathways.

Heteromeric G Protein and Monomeric G Protein - Side by Side Comparison

图02：单体G蛋白

Like the alpha subunit of large heteromeric G protein, small monomeric G protein alternate between an on state (bound to GTP) and an off state (bound to GDP). Therefore, monomeric G proteins function as binary switches that regulate cytosolic signalling pathways. The above GDP/GTP cycling is controlled by two types of regulatory proteins associated with monomeric G proteins. Guanine exchange factors (GEFs) promote the formation of active or GTP bound form of monomeric G protein (RAS protein), while GTPase activating proteins (空白）加速GTPase活性并促进单体G蛋白（RAS蛋白）的非活性或GDP结合形式

杂体G蛋白和单体G蛋白之间的相似之处是什么？

杂体G蛋白和单体G蛋白是G蛋白的两种类型。
杂体G蛋白的α亚基与单体G蛋白结构相关。
两种蛋白质都与GTP结合并将其水解为GDP，从而充当分子开关。
两种蛋白质催化的GTP水解速率可以通过间隙蛋白提高。
它们通过翻译后脂质修饰将它们束缚在质膜的内表面。

杂体G蛋白和单体G蛋白有什么区别？

是一个大型membrane-associat Heteromeric G蛋白质ed G protein made up of alpha (α), beta (β), and gamma (γ) subunits, while monomeric G protein is a small membrane-associated G protein made up of only the alpha subunit. Thus, this is the key difference between heteromeric G protein and monomeric G protein. Furthermore, heterotrimeric G protein binds to its cell surface receptor (G protein-coupled receptors) directly. On the other hand, monomeric G protein binds to its cell surface receptor (G protein-coupled receptors) indirectly.

下面的信息图列出了杂体G蛋白与单体G蛋白的差异，以与表格形式进行比较。