Yau King-Wai, Hardie Roger C
Solomon H. Snyder Department of Neuroscience and Center for Sensory Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Cell. 2009 Oct 16;139(2):246-64. doi: 10.1016/j.cell.2009.09.029.
Seeing begins in the photoreceptors, where light is absorbed and signaled to the nervous system. Throughout the animal kingdom, photoreceptors are diverse in design and purpose. Nonetheless, phototransduction-the mechanism by which absorbed photons are converted into an electrical response-is highly conserved and based almost exclusively on a single class of photoproteins, the opsins. In this Review, we survey the G protein-coupled signaling cascades downstream from opsins in photoreceptors across vertebrate and invertebrate species, noting their similarities as well as differences.
视觉始于光感受器,在那里光被吸收并向神经系统发出信号。在整个动物界,光感受器在设计和功能上各不相同。尽管如此,光转导——即吸收的光子转化为电反应的机制——却高度保守,几乎完全基于一类单一的光蛋白,即视蛋白。在这篇综述中,我们考察了脊椎动物和无脊椎动物物种光感受器中视蛋白下游的G蛋白偶联信号级联反应,指出它们的异同。