Cyclic nucleotide-gated (CNG) ion channels were first discovered in rod photoreceptors, where they are responsible for the primary electrical signal of the photoreceptor in response to light. CNG channels are highly specialized membrane proteins that open an ion-permeable pore across the membrane in response to the direct binding of intracellular cyclic nucleotides. CNG channels have been identified in a number of other tissues, including the brain, where their roles are only beginning to be appreciated. Recently, significant progress has been made in understanding the molecular mechanisms underlying their functional specializations. From these studies, a picture is beginning to emerge for how the binding of cyclic nucleotide is transduced into the opening of the pore and how this allosteric transition is modulated by various physiological effectors.

中文翻译：

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环状核苷酸门控离子通道。

环状核苷酸门控（CNG）离子通道首先在杆状感光器中发现，在那里它们负责感光器响应光的主要电信号。CNG通道是高度专门化的膜蛋白，可响应细胞内环状核苷酸的直接结合而在整个膜上打开离子可渗透的孔。CNG通道已在包括大脑在内的许多其他组织中被发现，在这些组织中，它们的作用才刚刚被人们所认识。近来，在理解其功能专长基础的分子机制方面已取得重大进展。根据这些研究，