The finger loop as an activation sensor in arrestin,Journal of Neurochemistry

当前位置： X-MOL 学术 › J. Neurochem. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

The finger loop as an activation sensor in arrestin
Journal of Neurochemistry ( IF 4.2 ) Pub Date : 2020-11-06 , DOI: 10.1111/jnc.15232
Sergey A Vishnivetskiy ₁ , Elizabeth K Huh ₁ , Eugenia V Gurevich ₁ , Vsevolod V Gurevich ₁

Affiliation

The finger loop in the central crest of the receptor-binding site of arrestins engages the cavity between the transmembrane helices of activated G-protein-coupled receptors. Therefore, it was hypothesized to serve as the sensor that detects the activation state of the receptor. We performed comprehensive mutagenesis of the finger loop in bovine visual arrestin-1, generated mutant radiolabeled proteins by cell-free translation, and determined the effects of mutations on the in vitro binding of arrestin-1 to purified phosphorylated light-activated rhodopsin. This interaction is driven by two factors, rhodopsin activation and rhodopsin-attached phosphates. Therefore, the binding of arrestin-1 to light-activated unphosphorylated rhodopsin is low. To evaluate the role of the finger loop specifically in the recognition of the active receptor conformation, we tested the effects of these mutations in the context of truncated arrestin-1 that demonstrates much higher binding to unphosphorylated activated and phosphorylated inactive rhodopsin. The majority of finger loop residues proved important for arrestin-1 binding to light-activated rhodopsin, with six mutations affecting the binding exclusively to this form. Thus, the finger loop is the key element of arrestin-1 activation sensor. The data also suggest that arrestin-1 and its enhanced mutant bind various functional forms of rhodopsin differently.

中文翻译：

手指环作为抑制素中的激活传感器

抑制素受体结合位点中央嵴的指环与活化的 G 蛋白偶联受体的跨膜螺旋之间的空腔接合。因此，假设用作检测受体激活状态的传感器。我们对牛视觉逮捕蛋白-1 中的指环进行了全面诱变，通过无细胞翻译产生了突变的放射性标记蛋白，并确定了突变对逮捕蛋白-1 与纯化的磷酸化光激活视紫红质体外结合的影响。这种相互作用是由两个因素驱动的，视紫红质激活和视紫红质附着的磷酸盐。因此，arrestin-1 与光激活的未磷酸化视紫红质的结合较低。为了评估手指环在识别活性受体构象中的作用，我们测试了这些突变在截短的arrestin-1 的背景下的影响，这表明与未磷酸化的活化和磷酸化的非活性视紫红质的结合要高得多。事实证明，大多数指环残基对于抑制蛋白 1 与光激活视紫红质的结合很重要，其中有六个突变仅影响与这种形式的结合。因此，手指环是arrestin-1激活传感器的关键元件。数据还表明，arrestin-1 及其增强的突变体以不同的方式结合各种功能形式的视紫红质。事实证明，大多数指环残基对于抑制蛋白 1 与光激活视紫红质的结合很重要，其中有六个突变仅影响与这种形式的结合。因此，手指环是arrestin-1激活传感器的关键元件。数据还表明，arrestin-1 及其增强的突变体以不同的方式结合各种功能形式的视紫红质。事实证明，大多数指环残基对于抑制蛋白 1 与光激活视紫红质的结合很重要，其中有六个突变仅影响与这种形式的结合。因此，手指环是arrestin-1激活传感器的关键元件。数据还表明，arrestin-1 及其增强的突变体以不同的方式结合各种功能形式的视紫红质。

更新日期：2020-11-06

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11