pmar1/phb homeobox genes and the evolution of the double-negative gate for endomesoderm specification in echinoderms
pmar1/phb homeobox genes and the evolution of the double-negative gate for endomesoderm specification in echinoderms
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DOI：
10.1242/dev.182139
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发表时间：
2020-01
期刊：
影响因子：
4.6
通讯作者：
A. Yamazaki;Yoshiaki Morino;M. Urata;M. Yamaguchi;T. Minokawa;Ryohei Furukawa;M. Kondo;H. Wada
中科院分区：
文献类型：
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作者：
A. Yamazaki;Yoshiaki Morino;M. Urata;M. Yamaguchi;T. Minokawa;Ryohei Furukawa;M. Kondo;H. Wada
摘要在几种模式动物中，胚胎发育的最早阶段受到谱系特异性基因的调控，如果蝇。海胆(海胆)胚胎发生是由pmar1的合子表达启动的，pmar1是一种配对的同源盒基因，被认为只存在于现代海胆(真海胆)的谱系中。在真棘球类中，Pmar1通过抑制裂解C(HESC)基因的毛发和增强子来促进内胚层的规范。在这里，我们已经确定了基础棘球蛋白(Cidarid)pmar1基因，它也促进内胚层规范，但不是通过抑制hESC来实现的。对相关基因的进一步搜索表明，其他棘皮动物也有与pmar1相关的基因，名为phb。对海星PHB蛋白的功能分析表明，与杀菌素Pmar1类似，它们通过一个未知的抑制物促进内胚层调控基因同源基因的激活，而不是hESC。基于这些结果，我们认为Pmar1可能概括了PHB在棘球蛋白早期多样化过程中的调节功能，并且在真棘球蛋白谱系中，额外的抑制子hESC被置于Pmar1的控制之下。这一案例为理解早期发育过程的差异提供了一个特殊的模型。摘要：发育基因调控网络的进化，包括海胆特有的同源盒基因pmar1，为理解早期发育过程的进化提供了一个特殊的模型。
ABSTRACT In several model animals, the earliest phases of embryogenesis are regulated by lineage-specific genes, such as Drosophila bicoid. Sea urchin (echinoid) embryogenesis is initiated by zygotic expression of pmar1, a paired-class homeobox gene that has been considered to be present only in the lineage of modern urchins (euechinoids). In euechinoids, Pmar1 promotes endomesoderm specification by repressing the hairy and enhancer of split C (hesC) gene. Here, we have identified the basal echinoid (cidaroid) pmar1 gene, which also promotes endomesoderm specification but not by repressing hesC. A further search for related genes demonstrated that other echinoderms have pmar1-related genes named phb. Functional analyses of starfish Phb proteins indicated that, similar to cidaroid Pmar1, they promote activation of endomesoderm regulatory gene orthologs via an unknown repressor that is not HesC. Based on these results, we propose that Pmar1 may have recapitulated the regulatory function of Phb during the early diversification of echinoids and that the additional repressor HesC was placed under the control of Pmar1 in the euechinoid lineage. This case provides an exceptional model for understanding how early developmental processes diverge. Summary: The evolution of the developmental gene regulatory network, including the sea urchin-specific homeobox gene pmar1, provides an exceptional model for understanding how early developmental processes evolved.