Pourquié Olivier
Stowers Institute for Medical Research, 1000E 50th Street, Kansas City, MO 64110, USA.
Mech Dev. 2004 Sep;121(9):1069-79. doi: 10.1016/j.mod.2004.05.002.
The vertebrate body is built on a metameric organization which consists of a repetition of functionally equivalent units, each comprising a vertebra, its associated muscles, peripheral nerves and blood vessels. This periodic pattern is established during embryogenesis by the somitogenesis process. Somites are generated in a rhythmic fashion from the presomitic mesoderm and they subsequently differentiate to give rise to the vertebrae and skeletal muscles of the body. Somitogenesis has been very actively studied in the chick embryo since the 19th century and many of the landmark experiments that led to our current understanding of the vertebrate segmentation process have been performed in this organism. Somite formation involves an oscillator, the segmentation clock whose periodic signal is converted into the periodic array of somite boundaries by a spacing mechanism relying on a traveling threshold of FGF signaling regressing in concert with body axis extension.
脊椎动物的身体是基于分节组织构建的，该组织由功能等效的单元重复组成，每个单元包括一块椎骨、其相关的肌肉、外周神经和血管。这种周期性模式在胚胎发育过程中通过体节发生过程建立。体节以有节奏的方式从生皮节中胚层产生，随后分化形成身体的椎骨和骨骼肌。自19世纪以来，鸡胚中的体节发生就得到了非常积极的研究，许多导致我们目前对脊椎动物分节过程理解的里程碑式实验都是在这种生物体中进行的。体节形成涉及一个振荡器，即分节时钟，其周期性信号通过一种间隔机制转化为体节边界的周期性阵列，该机制依赖于与身体轴延伸协同退行的FGF信号的移动阈值。
