Structural and Functional Analyses of Blue Light Photoreceptor Systems

本文主要以真藻、蓝藻和衣藻等藻类为研究对象，分析了蓝光感应光感受器-信号转导系统的分子结构和功能：(1)通过生化提取、分子克隆和测序（Iseki, Matsunaga, Murakami, Shiga）鉴定出一种用于真藻光运动的新型蓝光光感受器蛋白。Sugai霍利。渡边高桥)；(2)利用蓝细菌Synechocystfs sp. PCC 6803的蓝光不敏感突变体（蓝- 18需要异养生长响应（Wada））；(3)在蓝藻细菌中，腺苷酸环化酶参与的光信号转导途径已被证明具有红光/远红光和蓝光感知能力（Ohmori）；(4)在蓝光诱导的小球藻（Kamiya）质子泵送激活中，蛋白激酶的参与已在药理学上得到证实；(5)拟南芥原生质体细胞收缩过程中隐色素介导的膜去极化可归因于阴离子通道的激活和氯离子的流出（Iino）；(6)紫外- a光，而不是蓝光，已经在光谱上显示出控制衣藻配子体发生的作用（Saito, Matsuda, Watanabe）；(7)哺乳动物隐色素已被分子遗传学证明是必不可少的光感受器，用于光介导的小鼠昼夜节律（Yasui）。

Using mainly such algae as Euglena, cyanobacteria, and Chlamydomonas, molecular structures and functions of blue-light sensing photoreceptor-signal transuduction systems have been analyzed : (1) a novel blue-light photoreceptor protein has been identified for Euglena photomovement by biochemical extraction, subsequent molecular cloning and sequencing (Iseki, Matsunaga, Murakami, Shiga. Sugai, Hori. Takahashi, Watanabe) ; (2) blue-light insensitive mutants have been genarated in the cyanobacterium Synechocystfs sp. PCC 6803 using blue-1ight requiring heterotrophic growth response (Wada) ; (3) photo-signal transduction pathways in which adenylate cyclases are involved have been demonstrated for red/far-red and blue light sensing in cyanobacteria (Ohmori) ; (4) involvement of protein kinases has been phannacologically demonstrated in blue-light -induced activation of proton pumping in Chlorella (Kamiya) ; (5) the cryptochrome-mediated membrane depolarization in Arabidopsis protoplast cells proceeding shrinking has been ascribed to activation of anion channels and resultant efflux of chloride ions (Iino) ; (6) UV-A light, not blue light, has been shown action spectroscopically to control gametogenesis in Chlamydomonas (Saito, Matsuda, Watanabe) ; (7) mammalian cryptochromes have been molecular genetically shown to be essential as photoreceptors for light-mediated entraining of circadian rhythms in mice (Yasui).