Liu Chao, Montell Craig
Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, CA 93106, USA; Molecular, Cellular and Developmental Biology, University of California Santa Barbara, Santa Barbara, CA 93106, USA.
Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, CA 93106, USA; Molecular, Cellular and Developmental Biology, University of California Santa Barbara, Santa Barbara, CA 93106, USA.
Biochem Biophys Res Commun. 2015 Apr 24;460(1):22-5. doi: 10.1016/j.bbrc.2015.02.067.
Transient receptor potential (TRP) proteins are cation channels that comprise a superfamily of molecular sensors that enable animals to detect a wide variety of environmental stimuli. This versatility enables vertebrate and invertebrate TRP channels to function in a diversity of senses, ranging from vision to taste, smell, touch, hearing, proprioception and thermosensation. Moreover, many individual TRP channels are activated through a surprising range of sensory stimuli. The multitasking nature of TRP channels raises the question as to whether seemingly disparate activators gate TRPs through common strategies. In this regard, a recent major advance is the discovery that a phospholipase C (PLC)-dependent signaling cascade activates the TRP channels in Drosophila photoreceptor cells through generation of force in the lipid-bilayer. The premise of this review is that mechanical force is a unifying, common strategy for gating TRP channels. In addition to several TRP channels that function in mechanosensation and are gated by force applied to the cells, changes in temperature or alterations in the concentration of lipophilic second messengers through stimulation of signaling cascades, cause architectural modifications of the cell membrane, which in turn activate TRP channels through mechanical force. Consequently, TRPs are capable of functioning as stretch-activated channels, even in cases in which the stimuli that initiate the signaling cascades are not mechanical. We propose that most TRPs are actually mechanosensitive channels (MSCs), which undergo conformational changes in response to tension imposed on the lipid bilayer, resulting in channel gating.
瞬时受体电位（TRP）蛋白是阳离子通道，它们构成了一个分子传感器超家族，使动物能够检测各种各样的环境刺激。这种多功能性使脊椎动物和无脊椎动物的TRP通道在从视觉到味觉、嗅觉、触觉、听觉、本体感觉和温度感觉等多种感觉中发挥作用。此外，许多单个的TRP通道可通过一系列令人惊讶的感觉刺激而被激活。TRP通道的多任务性质引发了一个问题，即看似不同的激活剂是否通过共同的策略来开启TRP通道。在这方面，最近的一项重大进展是发现磷脂酶C（PLC）依赖性信号级联反应通过在脂质双层中产生力来激活果蝇光感受器细胞中的TRP通道。本综述的前提是机械力是开启TRP通道的一种统一的、常见的策略。除了在机械感觉中起作用并由施加到细胞上的力开启的几种TRP通道外，温度变化或通过刺激信号级联反应导致亲脂性第二信使浓度改变，会引起细胞膜的结构改变，进而通过机械力激活TRP通道。因此，即使在引发信号级联反应的刺激不是机械刺激的情况下，TRP也能够作为拉伸激活通道发挥作用。我们提出，大多数TRP实际上是机械敏感通道（MSC），它们会响应施加在脂质双层上的张力而发生构象变化，从而导致通道开启。
