Young Teddy, Rowland Jennifer Elizabeth, van de Ven Cesca, Bialecka Monika, Novoa Ana, Carapuco Marta, van Nes Johan, de Graaff Wim, Duluc Isabelle, Freund Jean-Noël, Beck Felix, Mallo Moises, Deschamps Jacqueline
Hubrecht Institute-KNAW and University Medical Center, 3584 CT Utrecht, The Netherlands.
Dev Cell. 2009 Oct;17(4):516-26. doi: 10.1016/j.devcel.2009.08.010.
Hox and Cdx transcription factors regulate embryonic positional identities. Cdx mutant mice display posterior body truncations of the axial skeleton, neuraxis, and caudal urorectal structures. We show that trunk Hox genes stimulate axial extension, as they can largely rescue these Cdx mutant phenotypes. Conversely, posterior (paralog group 13) Hox genes can prematurely arrest posterior axial growth when precociously expressed. Our data suggest that the transition from trunk to tail Hox gene expression successively regulates the construction and termination of axial structures in the mouse embryo. Thus, Hox genes seem to differentially orchestrate posterior expansion of embryonic tissues during axial morphogenesis as an integral part of their function in specifying head-to-tail identity. In addition, we present evidence that Cdx and Hox transcription factors exert these effects by controlling Wnt signaling. Concomitant regulation of Cyp26a1 expression, restraining retinoic acid signaling away from the posterior growth zone, may likewise play a role in timing the trunk-tail transition.
Hox和Cdx转录因子调节胚胎的位置身份。Cdx突变小鼠的轴向骨骼、神经轴和尾部泌尿直肠结构出现后体截断。我们发现，躯干Hox基因可刺激轴向延伸，因为它们在很大程度上能够挽救这些Cdx突变表型。相反，后部（旁系同源基因簇13）Hox基因在过早表达时可过早阻止后部轴向生长。我们的数据表明，从躯干Hox基因表达向尾部Hox基因表达的转变依次调节小鼠胚胎中轴向结构的构建和终止。因此，在轴向形态发生过程中，Hox基因似乎以不同方式协调胚胎组织的后部扩张，这是它们在确定从头到尾身份功能中的一个组成部分。此外，我们提供的证据表明，Cdx和Hox转录因子通过控制Wnt信号传导发挥这些作用。同样，Cyp26a1表达的协同调节，将视黄酸信号传导限制在远离后部生长区的位置，可能在调节躯干-尾部转变的时间方面也发挥作用。
