Modification of expression and cis-regulation of Hoxc8 in the evolution of diverged axial morphology
Modification of expression and cis-regulation of Hoxc8 in the evolution of diverged axial morphology
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DOI：
10.1073/pnas.95.5.2355
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发表时间：
1998-03-03
影响因子：
11.1
通讯作者：
Ruddle, FH
中科院分区：
文献类型：
--
作者：
Belting, HG;Shashikant, CS;Ruddle, FH
脊椎动物物种之间 Hox 基因表达的差异与轴向形态的差异有关。为了检验这种关系，我们比较了鸡和小鼠中 Hoxc8 的表达和转录调控。在这两个物种中，轴旁中胚层和神经管中 Hoxc8 的表达分别与中胸和臂的特征相关。在胚胎发生过程中，与小鼠相比，鸡中 Hoxc8 的激活存在时间延迟。近轴中胚层中的 Hoxc8 表达位于后轴水平，与小鼠 Hoxc8 表达相比，延伸的区域更小。这一发现与鸡的胸部区域比小鼠更短是一致的。此外，鸡 Hoxc8 早期增强子与小鼠对应物仅在几个特定核苷酸上有所不同，在转基因小鼠胚胎中将报告基因表达导向更靠后的区域。这些发现与轴向形态的多样化是通过改变发育控制基因的顺式调节。
Differential Hox gene expression between vertebrate species has been implicated in the divergence of axial morphology, To examine this relationship, we have compared expression and transcriptional regulation of Hoxc8 in chicken and mouse, In both species, expression of Hoxc8 in the paraxial mesoderm and neural tube is associated with midthoracic and brachial identities, respectively, During embryogenesis, there is a temporal delay in the activation of Hoxc8 in chicken compared with mouse, As a result, chicken Hoxc8 expression in the paraxial mesoderm is at a posterior axial level, extending over a smaller domain compared with mouse Hoxc8 expression, This finding is consistent with a shorter thoracic region in chicken compared with mouse, In addition, the chicken Hoxc8 early enhancer, differing from its mouse counterpart in only a few specific nucleotides, directs a reporter gene expression to a more posterior domain in transgenic mouse embryos, These findings are consistent with the concept that the diversification of axial morphology has been achieved through changes in cis-regulation of developmental control genes.