Structure and function of the transcription factor AREC3

1.从小鼠骨骼肌基因文库中克隆了三种编码AREC3/Six4蛋白的基因。序列分析表明，AREC3是一个新的六人基因家族成员，具有同源结构域和六个结构域作为保守结构域。这两个结构域都是特异DNA结合所必需的，潜在的反式激活结构域位于C末端。成肌细胞系C2C12在分化过程中，胞浆内有AREC3蛋白的产生。在大鼠出生后的视网膜形成过程中，基因产物的表达模式发生了巨大的变化。这些观察结果表明该基因参与了发育和分化过程。其他6个家族成员SIX2、Six3和Six5的cDNAs是从小鼠视网膜cDNA文库中分离得到的。原位杂交结果表明这些基因在视网膜中均有表达。同源结构域和六结构域是一个特异的dna结合域，其dna结合特异性在…中是保守的。更多SIX2、Six4和Six5.3。用免疫组织化学方法分析AREC3蛋白在新生大鼠视网膜和成年大鼠脑内的分布。在PND(出生后第1天)，AREC3位于神经节细胞的胞核，在PND4，除PND1外，蛋白表达在内核层，在PND7，表达在内核层的外细胞。PND13在神经节细胞中的表达由胞核移至胞浆，外段和内段均有表达。PND20后，未观察到核内分布。在大鼠脑内，AREC3蛋白主要分布在海马区和梨状皮质的胞核中，其mRNA主要分布在胞浆中。在小鼠胚胎中，从E9.5期开始在神经元细胞核中检测到AREC3蛋白。结果表明，AREC3在神经元和视网膜的分化和发育过程中起重要作用。较少

1. Three species of cDNA encoding AREC3/Six4 protein has been cloned from mouse skeletal muscle cDNA library. Sequence analysis revealed that the AREC3 is a member of new gene family of Six which has homeodomain and sixdomain as conserved domains. Both of the domains are necessary for specific DNA binding, and potential transactivation domain resides in the C terminal portion. During the differentiation of myoblast cell line C2C12, the productio of AREC3 protein is induced in the cytoplasm. During postnatal retina formation in rat, the expression pattern of the gene product varies dramatically. These observations suggest that the gene is involved in development and differentiation process.2. Other members of Six family genes, Six2, Six3 and Six5 cDNAs were isolated from mouse retina cDNA library. These genes were shown to be expressed in retina by in situ hybridization. Homeodomain and sixdomain function as a specific DNA binding domain, and the DNA binding specificity was conserved am … More ong Six2, Six4 and Six5.3. The distribution of AREC3 protein was analyzed by immunohistochemistry in newborn the rat retina and in the adult rat brain. In PND (postnatal day)1, the AREC3 resided in the nucleus of ganglion cells, in PND4, in addition to PND1, the protein was expressed in the inner nuclear layr and in PND7, the expression was observed in outer cells of the inner nuclear layr. In PND13, the expression was moved from the nucleus to the cytoplasm in ganglion cells, and the protein was expressed in outer segment and inner segment. After PND20, no distribution in the nucleus was observed. In rat brain, AREC3 protein was observed in the cell nucleus in hippocampus and in the piriform cortex and the mRNA was observed in the cytoplasm.4. In the mouse embryo, the AREC3 protein was detected in the nucleus of neuronal cells from stage E9.5. The production peaks at E10.5 to E11.5 and then gradually declined to undetectable level at E14.5These results indicates that the AREC3 plays an important role in differentiation and development of neuron and retina. Less