Ensminger P A, Chen X Y, Lipson E D
Department of Physics, Syracuse University, NY 13244-1130.
Photochem Photobiol. 1990 Jun;51(6):681-7.
We have measured fluence rate-response curves and action spectra for photogravitropism in Phycomyces wild type and in three recently isolated mutants with elevated phototropic thresholds. The action spectra were determined from least-squares fits of a sigmoidal function to the fluence rate-response data for each wavelength. The action spectrum for wild type has maxima near 383, 413, 452, and 490 nm and minima near 397, 425, and 469 nm. This photogravitropism action spectrum is very similar to the Phycomyces phototropic balance action spectrum between 413 but has significantly higher effectiveness below 400 nm and above 490 nm. These differences may be caused by dichroic effects of the oriented receptor pigment and/or by multiple receptor pigments. The action spectra of the three mutants differ significantly from one another and from that of wild type. Relative to the wild type spectrum, all three mutants exhibit a suppression in effectiveness near 425 nm, which is near the transmission peak of the broadband blue filter used to isolate the mutants.
我们已经测量了野生型毛霉以及最近分离出的三个具有较高向光性阈值的突变体的光重力反应曲线和光重力作用光谱。通过将S形函数对每个波长的光通量率响应数据进行最小二乘拟合来确定作用光谱。野生型的作用光谱在383、413、452和490nm附近有最大值，在397、425和469nm附近有最小值。这种光重力作用光谱与413之间的毛霉向光性平衡作用光谱非常相似，但在400nm以下和490nm以上具有明显更高的有效性。这些差异可能是由定向受体色素的二向色性效应和/或多种受体色素引起的。这三个突变体的作用光谱彼此之间以及与野生型的作用光谱都有显著差异。相对于野生型光谱，所有三个突变体在425nm附近的有效性都受到抑制，该波长接近用于分离突变体的宽带蓝色滤光片透射峰。
