Optochemical dissection of T-box gene-dependent medial floor plate development.
Optochemical dissection of T-box gene-dependent medial floor plate development.
复制标题
T-box基因依赖性内侧底板发育的光化学解剖。
DOI：
10.1021/cb5010178
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发表时间：
2015-06-19
影响因子：
4
通讯作者：
Chen JK
中科院分区：
文献类型：
--
作者：
Payumo AY;Walker WJ;McQuade LE;Yamazoe S;Chen JK
除了在中胚层发育中发挥细胞自主作用外，斑马鱼T-box转录因子no tail a （ntla）和spadetail （spt/tbx16）也是内侧底板（MFP）形成所必需的。在缺乏Ntla和Spt功能的斑马鱼胚胎中，后部MFP细胞完全缺失，遗传镶嵌分析表明，这两个T-box基因以非细胞自主的方式促进MFP的发育。基于这些观察，有人提出Ntla/ spt依赖的中胚层来源的信号是诱导后部而不是前部MFP细胞所必需的。为了研究Ntla和Spt调控MFP发育的机制，我们使用了光激活的笼形morpholinos （cMOs）通过时空控制来沉默这些T-box基因。我们发现，在早期原肠胚形成过程中，后部MFP的形成需要Ntla或Spt的活性，特别是在表观代谢和体细胞发生过程中向中线聚集的侧缘细胞。在没有Ntla和Spt功能的情况下，保持节点信号相关的MFP规范；然而，ntla中线细胞；SPT变形体表现出异常的形态发生运动，导致其前侧定位错误。我们的研究结果表明，Ntla和Spt对MFP沿前后轴的诱导没有差异；相反，T-box基因在边缘来源的细胞中起到冗余作用，促进MFP祖细胞的后伸。
In addition to their cell-autonomous roles in mesoderm development, the zebrafish T-box transcription factors no tail a (ntla) and spadetail (spt/tbx16) are required for medial floor plate (MFP) formation. Posterior MFP cells are completely absent in zebrafish embryos lacking both Ntla and Spt function, and genetic mosaic analyses have shown that the two T-box genes promote MFP development in a non-cell-autonomous manner. Based on these observations, it has been proposed that Ntla/Spt-dependent mesoderm-derived signals are required for the induction of posterior but not anterior MFP cells. To investigate the mechanisms by which Ntla and Spt regulate MFP development, we have used photoactivatable caged morpholinos (cMOs) to silence these T-box genes with spatiotemporal control. We find that posterior MFP formation requires Ntla or Spt activity during early gastrulation, specifically in lateral margin-derived cells that converge toward the midline during epiboly and somitogenesis. Nodal signaling-dependent MFP specification is maintained in the absence of Ntla and Spt function; however midline cells in ntla;spt morphants exhibit aberrant morphogenetic movements, resulting in their anterior mislocalization. Our findings indicate that Ntla and Spt do not differentially regulate MFP induction along the anterior-posterior axis; rather, the T-box genes act redundantly within margin-derived cells to promote the posterior extension of MFP progenitors.