HrNodal, the ascidian nodal-related gene, is expressed in the left side of the epidermis, and lies upstream of HrPitx
HrNodal, the ascidian nodal-related gene, is expressed in the left side of the epidermis, and lies upstream of HrPitx
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DOI：
10.1007/s00427-002-0242-3
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发表时间：
2002-10-01
影响因子：
2.4
通讯作者：
Nishida, H
中科院分区：
文献类型：
--
作者：
Morokuma, J;Ueno, M;Nishida, H
脊椎动物的发育过程中，包括中胚层诱导，神经诱导，和左右轴的形成，因为一些脊椎动物相关基因显示在中胚层谱系的左侧表达的基本作用是众所周知的。我们从海鞘Halocynthia roretzi中分离到了第一个非脊椎动物生殖相关基因HrNodal。在卵裂晚期和原肠胚阶段，HrNodal在几种不同的细胞谱系中瞬时和双侧表达。在左侧观察到尾芽期的表达不对称，但出乎意料地仅在胚胎的表皮中。我们还证明了HrNodal与HrPitx的关系，HrPitx是Pitx2基因的Halocynthia同源物。HrNodal过表达导致左侧HrPitch表达的紊乱。我们的研究结果表明，左右规范海鞘胚胎发生过程中涉及的HrNodal基因，和左侧的表达是进化保守的整个脊索动物分支。
The nodal-related genes are well known for their fundamental roles during vertebrate development, including mesoderm induction, neural induction, and left-right axis formation, as several nodal-related genes show left-sided expression in mesodermal lineages. We have isolated the first non-vertebrate nodal-related gene, HrNodal, from the ascidian Halocynthia roretzi. During the late cleavage and gastrula stages, HrNodal is transiently and bilaterally expressed in several different cell lineages. Expression at the tailbud stage is observed asymmetrically in the left side, but unexpectedly only in the epidermis of the embryo. We also demonstrate the relationship of HrNodal with HrPitx, a Halocynthia homologue of the Pitx2 gene. HrNodal overexpression results in the disturbance of left-sided HrPitx expression. Our results demonstrate that left-right specification during ascidian embryogenesis involves the HrNodal gene, and that the left-sidedness of the expression is evolutionarily conserved throughout the chordate clade.