U.S.-Netherlands Cooperative Research: Fourier Transform Infrared Spectroscopic Study of Visual Transduction Mechanism (Biophysics)

该奖项支持波士顿大学细胞生物物理学项目主任Kenneth J. Rothschild博士和荷兰奈梅亨大学生物化学系Willem J. de Grip博士在生物物理学领域开展为期30个月的合作研究项目。科学家和他们的研究小组成员正在合作研究视紫红质在视觉转导过程中作为关键组成部分的详细分子机制。需要解决的方面包括(1)视网膜的异构化如何导致视紫质中的瞬时信号表达，(2)在漂白序列的不同步骤中视网膜发色团的详细配置，(3)光感受器膜磷脂在视觉过程中的作用，(4)视紫红质α -螺旋在将转导信号从发色团传递到瞬时信号位点中的作用。傅里叶变换红外（FTIR）差分光谱将用于研究紫红质和光感受器膜中发生的光诱导构象变化。其中一些研究将涉及德·格里普博士实验室生产的经过修饰的视紫红质样本。这些样品包括同位素标记的发色团，蛋白水解和化学修饰的视紫红质，以及重组成不同脂质的视紫红质。在这里进行的实验旨在更好地理解当光线照射到眼睛视网膜时发生的基本过程。先进的生物物理和生物化学技术的结合将被应用于检测视网膜中紫红质分子因吸收光而发生的细微结构变化。这些变化最终会引起神经兴奋，我们将其解释为视觉，但确切的机制尚不清楚。Rothschild博士是将FTIR光谱应用于生物物理系统研究的领导者。De Grip博士是视紫红质生物化学领域的专家，他将准备本项目中许多要研究的样品。两位科学家和各自研究小组的成员一起工作，希望大大增加我们对视觉光化学的理解。

This award supports a 30-month cooperative research project in biophysics between Dr. Kenneth J. Rothschild, Director, Cellular Biophysics Program, Boston University, and Dr. Willem J. de Grip, Department of Biochemistry, University of Nijmegen, The Netherlands. The scientists and members of their research groups are collaborating in a study of the detailed molecular mechanism by which rhodopsin functions as a key component in the visual transduction process. Aspects to be addressed include (1) how isomerization of retinal leads to transient signal expression in rhodopsin, (2) the detailed configuration of the retinal chromophore at different steps in the bleaching sequence, (3) the role of photoreceptor membrane phospholipids in the visual process, and (4) the role of rhodopsin alpha-helices in transmitting the transductory signal from the chromophore to the transient signal sites. Fourier transform infrared (FTIR) difference spectroscopy will be used to study the light-induced conformational changes occurring in rhodopsin and photoreceptor membrane. Some of the studies will involve modified rhodopsin samples produced in Dr. De Grip's laboratory. These include samples with isotopically labeled chromophore, proteolytically and chemically modified rhodopsin, and rhodopsin reconstituted into different lipids. The experiments to be carried out here are aimed at understanding better the fundamental processes that take place when light strikes the retina of the eye. A combination of advanced biophysical and biochemical techniques will be applied to detect the subtle structural changes that occur in rhodopsin molecules in the retina in response to absorption of light. These changes ultimately give rise to the neural excitation we interpret as vision, but the exact mechanism is not yet understood. Dr. Rothschild is a leader in applying FTIR spectroscopy to the study of biophysical systems. Dr. De Grip is an expert in the field of rhodopsin biochemistry, and he will prepare many of the samples to be studied in this project. Working together, the two scientists and members of their respective research groups hope to increase significantly our understanding of the photochemistry of vision.