Shandala Tetyana, Takizawa Kazunaga, Saint Robert
Centre for the Molecular Genetics of Development, Adelaide University, Adelaide SA 5005, Australia.
Development. 2003 Apr;130(8):1505-13. doi: 10.1242/dev.00377.
The Drosophila dead ringer (dri, also known as retained, retn) gene encodes a nuclear protein with a conserved DNA-binding domain termed the ARID (AT-rich interaction domain). We show here that dri is expressed in a subset of longitudinal glia in the Drosophila embryonic central nervous system and that dri forms part of the transcriptional regulatory cascade required for normal development of these cells. Analysis of mutant embryos revealed a role for dri in formation of the normal embryonic CNS. Longitudinal glia arise normally in dri mutant embryos, but they fail to migrate to their final destinations. Disruption of the spatial organization of the dri-expressing longitudinal glia accounts for the mild defects in axon fasciculation observed in the mutant embryos. Consistent with the late phenotypes observed, expression of the glial cells missing (gcm) and reversed polarity (repo) genes was found to be normal in dri mutant embryos. However, from stage 15 of embryogenesis, expression of locomotion defects (loco) and prospero (pros) was found to be missing in a subset of LG. This suggests that loco and pros are targets of DRI transcriptional activation in some LG. We conclude that dri is an important regulator of the late development of longitudinal glia.
果蝇失音基因（dri，也称为保留基因，retn）编码一种核蛋白，该蛋白具有一个保守的DNA结合结构域，称为ARID（富含AT的相互作用结构域）。我们在此表明，dri在果蝇胚胎中枢神经系统的一部分纵向神经胶质细胞中表达，并且dri是这些细胞正常发育所需的转录调节级联反应的一部分。对突变胚胎的分析揭示了dri在正常胚胎中枢神经系统形成中的作用。纵向神经胶质细胞在dri突变胚胎中正常产生，但它们无法迁移到最终目的地。表达dri的纵向神经胶质细胞空间组织的破坏导致了在突变胚胎中观察到的轴突成束的轻微缺陷。与观察到的晚期表型一致，在dri突变胚胎中发现神经胶质细胞缺失（gcm）和极性反转（repo）基因的表达正常。然而，从胚胎发育的第15阶段开始，在一部分纵向神经胶质细胞中发现运动缺陷（loco）和prospero（pros）基因的表达缺失。这表明loco和pros是DRI在某些纵向神经胶质细胞中转录激活的靶标。我们得出结论，dri是纵向神经胶质细胞晚期发育的重要调节因子。
