Holland R W, García-Fernández J
School of Animal and Microbial Sciences, University of Reading, Whiteknights, UK.
Ontogenez. 1996 Jul-Aug;27(4):273-9.
Homeobox genes comprise a diverse multigene family encoding transcription factors, many of which are key control genes in early development. The roles of several homeobox gene subfamilies have been widely conserved through animal evolution, but there are detailed differences in homeobox gene number, genomic organisation and gene expression between taxa. We have compared Hox and other homebox genes between vertebrates and their closest living relatives, Amphioxus. The results suggest that after evolutionary divergence of these two lineages, homeobox and other genes were duplicated in the lineage leading to vertebrates, but that Amphioxus retained the archetypal homeobox gene organisation. We suggest that prior to vertebrate origins there was an intense phase of gene duplication, followed by recruitment of new developmental control genes to new roles. These genetic changes may have permitted the evolution of novel developmental and anatomical characters, and the origin of vertebrates.
同源框基因构成了一个多样的多基因家族，编码转录因子，其中许多是早期发育中的关键调控基因。几个同源框基因亚家族的作用在动物进化过程中得到了广泛的保留，但不同分类群之间在同源框基因数量、基因组组织和基因表达方面存在细节差异。我们比较了脊椎动物与其现存最亲近的亲属文昌鱼之间的Hox基因和其他同源框基因。结果表明，在这两个谱系发生进化分歧后，同源框基因和其他基因在导致脊椎动物的谱系中发生了复制，但文昌鱼保留了原始的同源框基因组织。我们认为，在脊椎动物起源之前，有一个基因复制的强烈阶段，随后新的发育调控基因被招募到新的角色中。这些基因变化可能促成了新的发育和解剖特征的进化以及脊椎动物的起源。
