牙鲆胚胎阶段pax6、tbx3和rx1基因的表达

Expression of pax6,tbx3 and rx1 genes during embryonic development in flounder(Paralichthys olivaceus)

在眼睛发育过程中,Paired Box 6(pax6)和T-Box Transcription Factor 3(tbx3)界定了视网膜发生区域,Retinal Homeobox Protein 1(rx1)确定了视杯的形成范围。本研究调查了pax6、tbx3和rx1基因是否在左右眼睛发生区域的表达范围存在差异。荧光定量PCR显示,牙鲆pax6、tbx3和rx1基因从受精后20 h开始表达。RNA整体原位杂交检测发现pax6基因在牙鲆胚胎左右眼睛发生区域表达,左侧表达范围较右侧略大,同时pax6在前脑以及神经管处也有表达;tbx3和rx1基因在牙鲆胚胎左右眼睛发生区域表达,左右侧表达范围无明显可见差异。提示我们,胚胎阶段眼睛发育过程中pax6在左右视网膜的表达范围存在的差异,是否可能导致牙鲆仔、稚鱼左右眼眶上和眶下成纤维细胞前体数量上存在差异,并最终导致变态阶段甲状腺激素诱导下的眼睛移动?

During eye development, pax6 and tbx3 define retina fieht, and rxl defines optic cup field. Weinvestigated whether pax6, rxl and tbx3 expressed differently between left and right retinas in Paralichthysolittceu.s. Quantity RT-PCR showed that pax6, tbx3and rxl began to express at 20 hours past frtilization.The whole nlounl RNA in situ hybridization further showed that pax6 expressed mainly in the left and rightretinas, and the expression region of left retina is a little bigger than that in right retina. The signal of tbx3and rxl was seen in the retina and their expressional region showed no visible difference between left and rightretinas. The difference in expression region of pax6 between left and right retinas reminds us whether thereexists a possibility that the difference will cause cell number difference between supraorbital and suboditalareas, which finally causes eye migration through the induction of thyroid hormone during metamorphosis.