Iglesias Ollé Laura, Perruchoud Chrystelle, Sanchez Paul Gerald Layague, Vogg Matthias Christian, Galliot Brigitte
Department of Genetics and Evolution, Institute of Genetics and Genomics (iGE3), Faculty of Sciences, University of Geneva, 30 Quai Ernest Ansermet, 1205 Geneva, Switzerland.
Biomedicines. 2024 Jun 8;12(6):1274. doi: 10.3390/biomedicines12061274.
head formation depends on an organizing center in which Wnt/β-catenin signaling, that plays an inductive role, positively regulates and , with Sp5 limiting expression and Zic4 triggering tentacle formation. Using transgenic lines in which the promoter drives eGFP expression in either the epidermis or gastrodermis, we show that promoter activity is differentially regulated in each epithelial layer. In intact animals, epidermal GFP activity is strong apically and weak along the body column, while in the gastrodermis, it is maximal in the tentacle ring region and maintained at a high level along the upper body column. During apical regeneration, :GFP is activated early in the gastrodermis and later in the epidermis. Alsterpaullone treatment induces a shift in apical expression towards the body column where it forms transient circular figures in the epidermis. Upon (RNAi), GFP activity is down-regulated in the epidermis while bud-like structures expressing GFP in the gastrodermis develop. (RNAi) reveals a negative autoregulation in the epidermis, but not in the gastrodermis. These differential regulations in the epidermis and gastrodermis highlight the distinct architectures of the network in the hypostome, tentacle base and body column of intact animals, as well as in the buds and apical and basal regenerating tips.
头部形成依赖于一个组织中心，在该中心中起诱导作用的Wnt/β-连环蛋白信号通路正向调节 ，并且Sp5限制 的表达，而Zic4触发触手形成。利用转基因品系，其中 启动子驱动表皮或胃皮层中eGFP的表达，我们发现 启动子活性在每个上皮层中受到不同的调节。在完整动物中，表皮GFP活性在顶端较强，沿体柱较弱，而在胃皮层中，它在触手环区域最大，并沿上体柱保持在高水平。在顶端再生过程中， :GFP在胃皮层中早期被激活，在表皮中晚期被激活。Alsterpaullone处理诱导顶端 表达向体柱转移，在表皮中形成短暂的圆形图案。在（RNAi）处理后，表皮中的GFP活性下调，而胃皮层中表达GFP的芽状结构发育。（RNAi）揭示了表皮中的负 自调节，但在胃皮层中没有。表皮和胃皮层中的这些差异调节突出了完整动物的口下叶、触手基部和体柱以及芽和顶端及基部再生尖端中 网络的不同结构。
