Tannahill D, Wardle F C
Department of Anatomy, University of Cambridge, United Kingdom.
Int J Dev Biol. 1995 Aug;39(4):549-58.
We describe the isolation and analysis in Xenopus of Xrel2, a novel member of the NF-kappa B/Rel protein family that remains to be described in other vertebrates. We show that Xrel2 is expressed throughout development but with higher levels in pre-gastrula embryos. Like other NF-kappa B/Rel proteins, Xrel2 protein is able to bind DNA at a kappa B-Motif. Ectopic expression of Xrel2 disrupts normal morphogenesis at the early gastrula stages suggesting that the NF-kappa B/Rel family have developmental functions at stages earlier than previously thought. We also show that the Xrel2 over-expression phenotype can be rescued by co-expression of I kappa B-alpha and that ectopic expression of I kappa B-alpha or I kappa B-gamma alone has no effect on development. Finally, we show that Xrel2 does not divert animal caps from an ectodermal to a mesodermal cell fate. Overall, these results suggest that the NF-kappa B/Rel family does have key functions in early vertebrate development, however, there is not a simple conservation of the Drosophila dorsal pathway.
我们描述了Xrel2在非洲爪蟾中的分离和分析，Xrel2是NF-κB/Rel蛋白家族的一个新成员，在其他脊椎动物中尚未见报道。我们发现Xrel2在整个发育过程中均有表达，但在原肠胚前期胚胎中的表达水平更高。与其他NF-κB/Rel蛋白一样，Xrel2蛋白能够在κB基序处结合DNA。Xrel2的异位表达会破坏早期原肠胚阶段的正常形态发生，这表明NF-κB/Rel家族在比之前认为的更早阶段就具有发育功能。我们还表明，共表达IκB-α可以挽救Xrel2过表达的表型，而单独异位表达IκB-α或IκB-γ对发育没有影响。最后，我们发现Xrel2不会使动物帽细胞从外胚层细胞命运转变为中胚层细胞命运。总体而言，这些结果表明NF-κB/Rel家族在脊椎动物早期发育中确实具有关键功能，然而，果蝇背侧信号通路并没有简单的保守性。
