Levin Nina, Yamakawa Shumpei, Morino Yoshiaki, Wada Hiroshi
Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan.
Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan.
Curr Top Dev Biol. 2022;146:1-24. doi: 10.1016/bs.ctdb.2021.10.001. Epub 2021 Dec 3.
Evolution of gene regulatory networks (GRN) that orchestrate the highly coordinated course of development, is made possible by the network's robust nature for incorporating change without detrimental developmental outcome. It can be considered that the upstream network regulating early development, has immense influence over succeeding pathways thus may be less subjected to evolutionary modification. However, recent studies show incorporation of novel genes in such early developmental pathways such as the echinoderm pmar1 as evidence for drastic change occurring high in the GRN hierarchy. Here we discuss the mechanisms that underlie divergence of early developmental pathways utilizing promising insights from the evolution of echinoderm early mesoderm specification pathway of Pmar1-HesC double negative gate found solely in the euechinoid sea urchin lineage, as well as examples from other groups such as Spiralia and Drosophila.
基因调控网络（GRN）协调着高度协调的发育过程，其稳健的特性使得在不产生有害发育结果的情况下纳入变化成为可能。可以认为，调控早期发育的上游网络对后续途径具有巨大影响，因此可能较少受到进化修饰。然而，最近的研究表明，诸如棘皮动物pmar1等新基因被纳入此类早期发育途径，这证明在GRN层次结构的较高位置发生了剧烈变化。在这里，我们利用仅在真海胆谱系中发现的Pmar1-HesC双负门的棘皮动物早期中胚层特化途径的进化所带来的有前景的见解，以及来自其他类群（如螺旋动物和果蝇）的例子，来讨论早期发育途径分歧背后的机制。
