红螯螯虾感光器Gqα的亚细胞定位(英文)  

Subcellular localization of the Cherax quadricarinatus photoreceptor Gqα subunit

作　　者：许燕[1] 赵云龙[2] 张慧琦[1] 

机构地区：[1]上海师范大学生命与环境科学学院,上海200234 [2]华东师范大学生命科学学院,上海200062

出　　处：《上海师范大学学报（自然科学版）》2006年第2期55-61,共7页Journal of Shanghai Normal University(Natural Sciences)

基　　金：上海市教委高校科技发展基金项目(02DK04).

摘　　要：利用免疫细胞化学的方法和电镜技术观察红螫螯虾感光器中Gq蛋白α亚基的亚细胞定位,结果表明：Gqα以膜结合形式定位于感杆束和以可溶性形式定位于细胞质中,Gqα定位的变化依赖于不同的光照条件．在暗适应后,Gqα主要分布于感杆束,细胞质中很少,感杆束与细胞质中胶体金颗粒的密度比为1．44±0．074；在(日)光适应后,密度比减少为0．61±0．021；在不同波长的光照处理后,Gqα定位有差异,感杆束与细胞质中胶体金颗粒的密度比由高至低,依次为：绿光(1．64±0．046)、红光(1．28±0．036)、蓝光(1．16±0．111)和黄光(0．96±0．099)．光调节的Gqα转位可能控制了能被枧紫红质激活的Gq蛋白的数量．研究表明：光波可影响感光细胞中膜结合和可溶性Gqα仪的比例,而这一结果可能是由被光激活的视紫红质的数量来控制的．The subcellular localization of the alpha subunit of the visual Gqct protein of Cherax quadricarinatus photoreceptors was investigated by immunoelectron microscopy. The Gqct was specifically localized in the rhabdom as a membrane - bound form and in the cytoplasm as a soluble form. The localization of Gqct changed under different light conditions. In the dark, more immunogold particles were detected in the rhabdom than in the cytoplasm. The density ratio in the rhabdom vs. the cytoplasm of immunogold particles within a photoreceptor cell was 1.44 ± 0. 074. In sunlight, this density ratio decreased to 0.61±0. 021. The localization of Gqα was found to be different under various light conditions. The density ratio was the highest when exposed to green light （ 1.64 ± 0. 046） ; this ratio decreased upon exposure to the following light condition： red light （1.28 ±0.036）, blue light （1. 16 ± 0. 111 ） and yellow light （0.96 ± 0. 099 ）. The light - modulated translocation possibly controls the amount of Gqα that can be activated by rhodopsin. The study suggested that different wavelengths of light can influence the ratio of membranebound and soluble forms of Gqα ; which could be a result of the amount of photoactivated rhodopsin.

关 键 词：红螯螯虾 感光器 Gqα亚基 亚细胞定位 免疫电镜 

分 类 号：Q952.6[生物学—动物学]