RNAseq of mouse presomitic mesoderm segments along the anteroposterior embryo axis

Somitogenesis is the segmentation of the developing embryonic body axis into somites and is guided by oscillating genes, which create waves of expression that travel across the presomitic mesoderm (PSM) from posterior to anterior. Upon arrival of a wave at the PSM's anterior end, a new somite is formed. To identify genes that are expressed in a wave-like pattern we dissected the PSM of four different mouse embryos (pre-turned), separated the left and right sides, and divided each into five segments, from posterior to anterior (sampling sites 1 to 5). Each segment was used to construct libraries for high-throughput RNA-sequencing. For one embryo, we also sequenced two somites.体节发生（Somitogenesis）是指发育中的胚胎体轴被分割为体节（somites）的过程，该过程由振荡基因调控。这些振荡基因可产生表达波，沿前体节中胚层（presomitic mesoderm，PSM）从后向前传播。当表达波抵达PSM的前端时，便会形成一个新的体节。为鉴定以波状模式表达的基因，我们解剖了4枚不同的翻转前（pre-turned）小鼠胚胎的PSM组织，将其左右两侧分离，并按从后到前的顺序将每侧均划分为5个区段（采样位点1至5）。每个区段均被用于构建高通量RNA测序文库。针对其中1枚胚胎，我们还对2个体节进行了测序。