空间里的时间:微重力等环境下的生物节律研究

生物钟是地球上的生物为适应环境周期性变化经历长期演化而来的内在机制.在分子水平上受生物钟基因及其他相关基因的调节；在组织水平上，生物钟由主生物钟和外周生物钟组成.生物钟对于各种生物的生理、认知和行为等具有重要功能，是生物适应环境的决定因素之一.空间环境下的微重力、辐射、光照条件、社会性因素等与地面存在很大差异，这些因素均可能导致节律紊乱，影响生物的生理及环境适应性.因此，对地外生命的研究也应该考虑生物钟因素.对航天员而言，节律紊乱可引起睡眠障碍，并且对骨肌系统、神经系统、心血管系统及内分泌系统等造成不利影响，导致人的认知和工效水平下降.在未来空间生命探索以及航天员健康保障研究中，生物钟是一个不可忽视的重要因素. 

Time in Space:Advances in the Study of Circadian Rhythms under Microgravity

Circadian clocks,derived from long-term evolution,are endogenous mechanisms which endow the organisms to adapt to the daily cycling environment on Earth.At the molecular level,circadian clocks are controlled by a series of clock genes and other clock associated regulators.At the tissue level,circadian systems are composed of master and peripheral clocks.Circadian clocks affect physiology,cognition and behavior of almost all organisms,which dictate their adaptability to the environment.Space environmental factors,e.g.,microgravity,radiation,lighting condition and social factors,dramatically differ from those on the Earth,which may lead to impacts on circadian rhythms.Therefore,circadian clock needs to be considered in the study of space life sciences.Misalignment in circadian rhythms leads to sleep disorder and affects the skeleton-muscular system,neural system,cardio-vascular system,endocrine system,and so on,and decreases the performance of astronauts.Circadian clock will be a critical factor in future space life research and in study of astronaut health and performance.