Turner E E, Jenne K J, Rosenfeld M G
Howard Hughes Medical Institute, Eukaryotic Regulatory Biology Program, University of California, San Diego.
Neuron. 1994 Jan;12(1):205-18. doi: 10.1016/0896-6273(94)90164-3.
The identification and molecular characterization of Brn-3.2 has revealed a family of Brn-3-related mammalian POU proteins that share homology with the C. elegans developmental regulator Unc-86 and extended similarity with the Drosophila neurodevelopmental gene I-POU, which defines a novel POU-IV box. Brn-3.2 exhibits DNA binding properties similar to those of Brn-3.0, but its expression is uniquely regulated by retinoic acid in teratocarcinoma and neuroblastoma cells. In the developing PNS and retina, the expression pattern of Brn-3.2 is similar to that of Brn-3.0. In the caudal CNS (spinal cord, hindbrain, and midbrain) Brn-3.2 and Brn-3.0 are initially coexpressed, but diverge later in development. Rostral to the midbrain, Brn-3.2 and Brn-3.0 exhibit nonoverlapping patterns of expression, suggesting divergence of gene function in more recently evolved structures. Our analysis suggests that in the CNS Brn-3.2 is selectively expressed in postmitotic neurons, implying a role in specifying terminally differentiated neuronal phenotypes.
Brn-3.2的鉴定和分子特征揭示了一个与Brn-3相关的哺乳动物POU蛋白家族，它们与秀丽隐杆线虫发育调节因子Unc-86具有同源性，并且与果蝇神经发育基因I-POU具有广泛的相似性，后者定义了一个新的POU-IV框。Brn-3.2表现出与Brn-3.0相似的DNA结合特性，但其表达在畸胎瘤和神经母细胞瘤细胞中受到视黄酸的独特调控。在发育中的周围神经系统和视网膜中，Brn-3.2的表达模式与Brn-3.0相似。在尾部中枢神经系统（脊髓、后脑和中脑）中，Brn-3.2和Brn-3.0最初共同表达，但在发育后期出现差异。在中脑前方，Brn-3.2和Brn-3.0表现出不重叠的表达模式，这表明在最近进化的结构中基因功能存在差异。我们的分析表明，在中枢神经系统中，Brn-3.2在有丝分裂后的神经元中选择性表达，这意味着它在确定终末分化的神经元表型中发挥作用。
