de Grip Willem J, Ganapathy Srividya
Leiden Institute of Chemistry, Department of Biophysical Organic Chemistry, Leiden University, Leiden, Netherlands.
Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands.
Front Chem. 2022 Jun 22;10:879609. doi: 10.3389/fchem.2022.879609. eCollection 2022.
The first member and eponym of the rhodopsin family was identified in the 1930s as the visual pigment of the rod photoreceptor cell in the animal retina. It was found to be a membrane protein, owing its photosensitivity to the presence of a covalently bound chromophoric group. This group, derived from vitamin A, was appropriately dubbed retinal. In the 1970s a microbial counterpart of this species was discovered in an archaeon, being a membrane protein also harbouring retinal as a chromophore, and named bacteriorhodopsin. Since their discovery a photogenic panorama unfolded, where up to date new members and subspecies with a variety of light-driven functionality have been added to this family. The animal branch, meanwhile categorized as type-2 rhodopsins, turned out to form a large subclass in the superfamily of G protein-coupled receptors and are essential to multiple elements of light-dependent animal sensory physiology. The microbial branch, the type-1 rhodopsins, largely function as light-driven ion pumps or channels, but also contain sensory-active and enzyme-sustaining subspecies. In this review we will follow the development of this exciting membrane protein panorama in a representative number of highlights and will present a prospect of their extraordinary future potential.
视紫红质家族的首个成员及同名物于20世纪30年代被鉴定为动物视网膜中视杆光感受器细胞的视觉色素。它被发现是一种膜蛋白，其光敏性归因于一个共价结合的发色团的存在。这个源自维生素A的基团被恰当地命名为视黄醛。20世纪70年代，在一种古生菌中发现了该物种的微生物对应物，它也是一种含有视黄醛作为发色团的膜蛋白，并被命名为细菌视紫红质。自它们被发现以来，一幅光致全景图展开了，到目前为止，这个家族已经增添了具有各种光驱动功能的新成员和亚种。与此同时，动物分支被归类为2型视紫红质，结果在G蛋白偶联受体超家族中形成了一个大亚类，并且对于光依赖型动物感觉生理学的多个要素至关重要。微生物分支，即1型视紫红质，主要作为光驱动离子泵或通道发挥作用，但也包含具有感觉活性和维持酶活性的亚种。在这篇综述中，我们将按照一些具有代表性的要点来讲述这一令人兴奋的膜蛋白全景图的发展历程，并展望它们非凡的未来潜力。
