摘要/Abstract
半个世纪以来，动物地磁导航得到了广泛而深入的研究，然而其背后的磁感应机理还不清楚.1978年，Schulten等提出自由基对机理可能是生物磁感应的内在机制.近年来，这一假设得到发展和完善，提出隐花色素蛋白是生物的磁感应分子的观点.由于生物体内环境的复杂性和隐花色素蛋白的易光解特性，生物磁感应自由基对机理的研究受到很大限制.为了深入研究生物磁感应自由基对机理，人们构建了磁感应模型体系，大大简化了生物环境的复杂性，从不同方面开展了磁感应研究.基于国内外****的研究成果，主要介绍隐花色素磁感应和各种模型体系相关研究进展，简要总结并提出生物磁感应自由基对机理研究中亟待解决的问题.
关键词: 隐花色素, 生物磁感应, 自由基对机理, 黄素, 模型体系
Although it has been widely and deeply studied for half a century that many animals sense the Earth's magnetic field for navigation, the exact mechanism of magnetoreception is still largely unclear. In 1978, Schulten et al. proposed that the radical-pair mechanism provides the operational principle of light-depended biological magnetoreception. This hypothesis has been developed in recent years, assuming that the flavoprotein and blue-light photoreceptor cryptochrome is the biological magnetosensitive molecule undergoing light-triggered radical-pair dynamics. Evidence is accumulating in favor of this radical-pair-based magnetoreception and the cryptochrome hypothesis. However, Complex in vivo and photochemical properties of cryptochrome hamper to identify the exact mechanism of biological magnetoreception. According to the radical-pair mechanism, magnetic fields may alter the rate and yields of chemical reactions involving spin-correlated radical pairs (SCRP) as intermediates. Such magnetic field effects (MFE) have been studied in detail in a variety of chemical systems both exper-imentally and theoretically. To improve the understanding of the radical-pair mechanism and the magnetosensitivity of cryp-tochrome, several artificial model systems have been constructed and studied by different analytical means. Model systems greatly simplify the complexity of the biological environment and allow for systematic variation of properties. Based on the research of domestic and foreign scholars, we here review studies on the radical-pair-based biological magnetoreception and magnetosensitivity of cryptochrome, and we discuss the recent progresses on three major artificial model systems:(1) a variety of flavin-based radical pair systems in mixture solution, micellar solution or protein environment; (2) chemical magnetosensitive model molecules, e.g. flavin adenine dinucleotide (FAD), a carotenoid-porphyrin-fullerene triad (C-P-F) and a flavin-tryptophan dyad (F10T); (3) artificial flavoprotein magnetosensors, i.e., a family of simplified, adaptable proteins-flavomaquettes. We also briefly summarize characteristics and advantages of those different artificial model systems and raise some key scientific issues in the further research on radical-pair-based biological magnetoreception.
Key words: cryptochrome, biological magnetoreception, radical-pair mechanism, flavin, model systems
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