Seo H C, Drivenes O, Ellingsen S, Fjose A
Department of Molecular Biology, University of Bergen, HIB-Biobuilding, N-5020, Bergen, Norway.
Gene. 1998 Aug 17;216(1):39-46. doi: 10.1016/s0378-1119(98)00328-x.
Both the Drosophila homeobox gene sine oculis and its murine homologue Six3 have regulatory functions in eye development. In zebrafish, in addition to two previously reported homologues of murine Six3, we have identified a related gene (six7). Although the deduced Six7 protein shares less than 68% sequence identity with the other known zebrafish Six3-like proteins, the embryonic expression patterns have highly conserved features. The six7 transcripts are first detected in involuting axial mesendoderm and, subsequently, in the overlying neurectoderm from which the forebrain and optic primordia develop. Similar to the two other zebrafish Six3 homologues, the expression boundaries of six7 correspond quite closely with the edges of the optic vesicles. Hence, the partially overlapping expression domains of these three six genes probably contribute to anteroposterior specification and in defining the eye primordia.
果蝇同源异型框基因无眼和其小鼠同源物Six3在眼睛发育中均具有调控功能。在斑马鱼中，除了先前报道的两种小鼠Six3同源物外，我们还鉴定出一个相关基因（six7）。尽管推导的Six7蛋白与其他已知的斑马鱼Six3样蛋白的序列同一性不到68%，但其胚胎表达模式具有高度保守的特征。six7转录本首先在卷入的轴向中内胚层中被检测到，随后在上覆的神经外胚层中被检测到，前脑和视原基由此发育而来。与其他两种斑马鱼Six3同源物类似，six7的表达边界与视泡边缘相当紧密地对应。因此，这三个six基因部分重叠的表达域可能有助于前后轴的特化并界定眼原基。
