Multiple noggins in vertebrate genome:: cloning and expression of noggin2 and noggin4 in Xenopus laevis
Multiple noggins in vertebrate genome:: cloning and expression of noggin2 and noggin4 in Xenopus laevis
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DOI：
10.1016/j.modgep.2005.06.007
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发表时间：
2006-01-01
影响因子：
1.2
通讯作者：
Zaraisky, AG
中科院分区：
文献类型：
--
作者：
Eroshkin, FM;Ermakova, GV;Zaraisky, AG
Noggin 是由斯佩曼组织者细胞分泌的神经诱导剂。直到最近，在所有测试的脊椎动物中才发现了一个头蛋白基因。唯一的例外是斑马鱼，其中克隆了两个与 noggin 密切同源的基因，分别称为 noggin1 和 noggin3，以及一个与它们更加不同的基因，noggin2。然而，三个斑马鱼头的发现完全归因于鱼类进化分支中特定的基因组重复。然而，最近发现热带爪蟾还有额外的头蛋白同源物，称为 noggin2 [Fletcher, R.B.、Watson, A.L.、Harland, R.M. （2004）。热带非洲爪蟾 noggin1 和 noggin2 在早期发育中的表达：四足动物中的两个 noggin 基因。基因表达。模式5, 225-230]，表明脊椎动物门中至少有两个独立的头蛋白基因。现在，我们报告了在非洲爪蟾、鸡和河豚等进化遥远的物种中鉴定出两种新的头蛋白同源物。其中一个 noggins 是 Xtropicalis 和斑马鱼 noggin2 的直系同源物，而另一种被命名为 noggin4，之前并不为人所知。在非洲爪蟾胚胎中，noggin2 的表达与热带爪蟾中的对应物非常相似：它从神经板前缘的神经形成开始，然后主要在前脑和背侧后脑中继续。同时，noggin4从原肠胚形成开始就在整个外胚层表达，在预期的前神经外胚层中局部表达最大。后来，它广泛表达于胚胎的背侧，包括神经管、眼睛、耳泡、颅板、鳃弓和体节。这里提供的数据表明脊椎动物门至少包含三个不同的头蛋白基因。 (C) 2005 Elsevier B.V. 保留所有权利。
Noggin is a neural inducer secreted by cells of the Spemann organizer. A single noggin gene was identified until very recently in all tested vertebrates. The only exception was zebrafish, in which two close homologs of noggin, named noggin1 and noggin3, and one gene more diverged from them, noggin2, were cloned. Nevertheless, finding of three zebrafish noggins was attributed exclusively to specific genomic duplications in the fish evolutionary branch. However, very recently it was shown that Xenopus tropicalis have additional noggin homolog, called noggin2 [Fletcher, R.B., Watson, A.L., Harland, R.M. (2004). Expression of Xenopus tropicalis noggin1 and noggin2 in early development: two noggin genes in a tetrapod. Gene Expr. Patterns 5, 225-230], which indicates at least two independent noggin genes in vertebrate phylum. Now we report identification of two novel noggin homologs in each of so evolutionary distant species as Xenopus laevis, chicken and fugu. One of these noggins is ortholog of the X tropicalis and zebrafish noggin2, whereas another, named noggin4, was not known previously. In the X. laevis embryos, the expression of noggin2 very resembles that of its counterpart in X. tropicalis: it begins with neurulation at the anterior margin of the neural plate and, afterward, continues mainly in the forebrain and dorsal hindbrain. At the same time, noggin4 is expressed starting from the beginning of gastrulation, throughout the ectoderm, with a local expression maximum in the prospective anterior neurectoderm. Later, it is widely expressed on the dorsal side of embryo, including neural tube, eyes, otic vesicles, cranial placodes, branchial arches, and somites. The data presented here demonstrate that the vertebrate phylum contains at least three distinct noggin genes. (C) 2005 Elsevier B.V. All rights reserved.