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来自无形的形式:胚胎那令人敬畏的力量

Form from the Formless: The Awesome Power of the Embryo
课程网址: http://videolectures.net/mitworld_sive_embryo/  
主讲教师: Hazel Sive
开课单位: 麻省理工学院
开课时间: 2013-04-19
课程语种: 英语
中文简介:
一个细胞是如何变成一个复杂的有机体的?这个问题的魅力和挑战,Hazel Sive说,“每天把我从床上赶下来,让我工作很长时间,并让我对来到这里感到兴奋。”Sive的Whitehead实验室调查胚胎发育过程,寻找细胞如何组织和形成组织和器官的线索。一个胚胎不仅必须决定要生长什么样的细胞,还必须将它们沿三维精确排列。当胚胎发育时,细胞互相发出信号移动到特定的位置,或者调节蛋白发出命令,让细胞以某种方式排列自己。Sive对大脑结构的进化特别感兴趣。斑马鱼是她的模特。这条鱼细小透明的胚胎使她能够“无创性地直视大脑”。Sive播放了一段视频,显示了大脑是如何从一片细胞中形成的,这些细胞首先卷成一根管子。然后,出现了三个与关键神经功能相对应的不同区域。如果负责这种早期大脑结构模式的基因出了问题,斑马鱼胚胎可能会出现一个脑腔,这个脑腔太大或太小,不允许神经组织进行复杂的折叠。这个早期的过程在所有的大脑中都以同样的方式发生,不管是斑马鱼还是人类,sive说。因此,对突变斑马鱼大脑和在异常发育中起作用的基因的研究揭示了人类的大脑功能异常,包括自闭症和智力低下。
课程简介: How does a single cell become a complex organism? The fascination and challenge of this question, says Hazel Sive, “drives me out of bed each day, makes me work long hours and keeps me excited about coming here.” Sive’s Whitehead lab investigates developing embryos for clues about how cells organize and form tissues and organs. Not only must an embryo determine what kinds of cells to grow, it must also place them in precise patterns, along three dimensions. As the embryo develops, cells signal to each other to move to a specific position, or a regulatory protein sends a command for a cell to align itself in a certain way. Sive’s particularly interested in the evolution of brain structure. Zebrafish serve as her model. The tiny, transparent embryos of this fish enable her to “look directly into the brain in a noninvasive way.” Sive plays a video showing how a brain forms from a sheet of cells that first rolls up into a tube. Then, three distinct areas emerge that correspond to key neural functions. If a gene responsible for this patterning of early brain structure goes awry, then the zebra fish embryo may emerge with a brain cavity that’s too big or too small to permit the intricate folding of neural tissue. This early process transpires the same way in all brains, whether zebrafish or human, says Sive. So study of mutant zebra fish brains and the genes that play a role in abnormal development shed light on brain malfunction in humans, including autism and mental retardation.
关 键 词: 单一的细胞; 胚胎形成; 调节蛋白; 脑结构; 神经组织
课程来源: 视频讲座课
最后编审: 2020-06-02:liqy
阅读次数: 41