Liu J K, Ghattas I, Liu S, Chen S, Rubenstein J L
Center for Neurobiology and Psychiatry, Department of Psychiatry, University of California at San Francisco, 94143-0984, USA.
Dev Dyn. 1997 Dec;210(4):498-512. doi: 10.1002/(SICI)1097-0177(199712)210:4<498::AID-AJA12>3.0.CO;2-3.
The Dlx gene family encodes homeodomain proteins that are required for forebrain and craniofacial development. Towards elucidating the roles for each of these genes, we have isolated cDNA clones encoding the full-coding sequence for murine Dlx-5 and partial coding sequence for murine Dlx-6. Three different classes of sense Dlx-5 cDNA clones were characterized, two of which lack the homeobox. We also identified an antisense Dlx-6 transcript. Genomic analysis shows that the Dlx-5 and -6 genes are linked. Biochemical analysis using gel shift assays demonstrate that DLX-1, -2 and -5 have very similar DNA-binding properties. The expression of Dlx-1, -2, -5, -6 and antisense Dlx-1 and -6 was studied in the midgestation mouse brain. We found that the Dlx genes are expressed in overlapping patterns at different stages of differentiation within the primordia of the basal ganglia. Dlx-1 and -2 are expressed in the least mature cells (in the ventricular and subventricular zones). Dlx-5 appears to be co-expressed with Dlx-1 and -2 in the SVZ, but is also expressed in the postmitotic cells of the mantle. Dlx-6 expression is strongest in the mantle. Antisense Dlx-1 and -6 have their highest expression in the SVZ. These results suggest that each of these Dlx genes may have a distinct role in different steps of differentiation in the basal ganglia.
Dlx基因家族编码前脑和颅面发育所需的同源结构域蛋白。为了阐明这些基因各自的作用，我们分离了编码小鼠Dlx - 5全编码序列和小鼠Dlx - 6部分编码序列的cDNA克隆。对三种不同类型的有义Dlx - 5 cDNA克隆进行了表征，其中两种缺乏同源框。我们还鉴定出一种反义Dlx - 6转录本。基因组分析表明Dlx - 5和 - 6基因是连锁的。使用凝胶迁移试验的生化分析表明，DLX - 1、- 2和 - 5具有非常相似的DNA结合特性。研究了Dlx - 1、- 2、- 5、- 6以及反义Dlx - 1和 - 6在妊娠中期小鼠脑中的表达。我们发现Dlx基因在基底神经节原基内不同分化阶段以重叠模式表达。Dlx - 1和 - 2在最不成熟的细胞（脑室和室下区）中表达。Dlx - 5似乎与Dlx - 1和 - 2在室下区共表达，但也在套层的有丝分裂后细胞中表达。Dlx - 6在套层中的表达最强。反义Dlx - 1和 - 6在室下区的表达最高。这些结果表明，这些Dlx基因中的每一个可能在基底神经节分化的不同步骤中具有独特的作用。
