ANEURAL PHOTOSENSORY TRANSDUCTION IN STENTOR COERULEUS

蓝柱体是一种单细胞杂毛症，具有这两种光 强度和颜色(波长)--感觉“视觉”，代表第一个 基于stentorin的明显可识别的“视觉感觉系统” 光感受器，作为一种成熟的基于RhodSpin的替代品 高等动物的视觉感觉系统。这种神经性的有机体也是 能够感知光传播的方向。光感测是 表现为有机体的纤毛跳动反转。这个 该电池中的光敏过程可以示意性地描述为 以下是： 光信号由光感受器吸收到信号的产生和 放大反应(睫状卒中反转) 我们建议研究光诱导质子的可能参与。 从感光器释放(ph值变化)作为一种主要机制 产生光信号。质子形式的初始信号 光感受器复合体的释放被认为是引发 随后的转导步骤包括钙离子从细胞内流 细胞外介质，从而放大初始光信号。它是 提出钙离子内流导致支架细胞逆转 纤毛拍打方向，随后避开有害光线 消息来源。 具体地说，我们计划阐明关键感官的机制 转导步骤。光感受器stentorin将被分离并 进一步表征了其在溶液中和In中的主要光过程 光感受器细胞器(色素颗粒)以及 牢房将被调查。从激发态释放质子的作用 作为初始感觉信号的stentorin状态(ph值变化--诱发 受体电位)将通过使用颜料中的ph探针来说明 颗粒包埋脂质体和体内实验。我们认为，一个瞬变者 色素释放质子引起的细胞内pH下降 颗粒是一种电信号，可以打开体内的钙 细胞/纤毛膜。钙离子的内流然后触发纤毛 打败了反转。这一假设将在目前得到进一步检验。 学习。

Stentor coeruleus, a unicellular hetrotrich,possesses both light intensity-and color (wavelength)-sensory "visions", representing the first clearly identifiable "visual sensory system" based on stentorin as the photoreceptor,as an alternative to the well established rhodospin-based visual sensory system in higher animals. This aneural organism is also able to perceive the direction of light propagation. Light sensing is manifested in the form of ciliary beat reversal by the organism. The photosensory process in this cell can be described schematically as follows: Light signal to Absorption by photoreceptor to Signal generation and amplification to Response (ciliary stroke reversal) We propose to study the possible involvement of a light-induced proton release (ph change) from the photoreceptor as a primary mechanism for the generation of a light signal. The initial signal in the form of proton release from the photoreceptor complexes has been suggested to trigger subsequent transduction steps that include calcium ion influx from the extracellular medium,thus amplifying the initial light signal. It is proposed that the calcium ion influx causes stentor cell to reverse the ciliary beat direction and subsequently steer away from the harmful light source. Specifically, we plan to elucidate the mechanisms of the key sensory transduction steps. The photoreceptor stentorin will be isolated and further characterized,and its primary photoprocesses in solution and in the photoreceptor organelle (pigment granule) as well as in the intact cell will be investigated. The role of proton release from the excited state of stentorin as an initial sensory signal (a ph change-evoked receptor potential) will be illustrated by using ph probes in the pigment granule-entrapped liposomes and in vivo. We propose that a transient intracellular ph drop resulting from the proton release from pigment granules serves as an electrical signal to open calcium in the cell/ciliary membranes. The influx of calcium ions then trigger a ciliary beat reversal. This hypothesis will be further tested in the present study.