Chung Sangmi, Sonntag Kai-C, Andersson Therese, Bjorklund Lars M, Park Jae-Joon, Kim Dong-Wook, Kang Un Jung, Isacson Ole, Kim Kwang-Soo
Udall Parkinson's Disease Research Center of Excellence, Neuroregeneration Laboratory, McLean Hospital/Harvard Medical School, Belmont, MA 02478, USA.
Eur J Neurosci. 2002 Nov;16(10):1829-38. doi: 10.1046/j.1460-9568.2002.02255.x.
Nurr1 is a transcription factor critical for the development of midbrain dopaminergic (DA) neurons. This study modified mouse embryonic stem (ES) cells to constitutively express Nurr1 under the elongation factor-1alpha promoter. The Nurr1-expression in ES cells lead to up-regulation of all DA neuronal markers tested, resulting in about a 4- to 5-fold increase in the proportion of DA neurons. In contrast, other neuronal and glial markers were not significantly changed by Nurr1 expression. It was also observed that there was an additional 4-fold increase in the number of DA neurons in Nurr1-expressing clones following treatment with Shh, FGF8 and ascorbic acid. Several lines of evidence suggest that these neurons may represent midbrain DA neuronal phenotypes; firstly, they coexpress midbrain DA markers such as aromatic L-amino acid decarboxylase, calretinin, and dopamine transporter, in addition to tyrosine hydroxylase and secondly, they do not coexpress other neurotransmitters such as GABA or serotonin. Finally, consistent with an increased number of DA neurons, the Nurr1 transduction enhanced the ability of these neurons to produce and release DA in response to membrane depolarization. This study demonstrates an efficient genetic manipulation of ES cells that facilitates differentiation to midbrain DA neurons, and it will serve as a framework of genetic engineering of ES cells by key transcription factor to regulate their cell fate.
Nurr1是一种对中脑多巴胺能（DA）神经元发育至关重要的转录因子。本研究对小鼠胚胎干细胞（ES细胞）进行改造，使其在延伸因子-1α启动子的控制下组成性表达Nurr1。ES细胞中Nurr1的表达导致所有检测的DA神经元标志物上调，使DA神经元的比例增加了约4至5倍。相比之下，其他神经元和神经胶质标志物并未因Nurr1的表达而发生显著变化。还观察到，在用Shh、FGF8和抗坏血酸处理后，表达Nurr1的克隆中DA神经元的数量又增加了4倍。多项证据表明，这些神经元可能代表中脑DA神经元表型；首先，除酪氨酸羟化酶外，它们还共同表达中脑DA标志物，如芳香族L-氨基酸脱羧酶、钙视网膜蛋白和多巴胺转运体，其次，它们不共同表达其他神经递质，如GABA或5-羟色胺。最后，与DA神经元数量增加一致，Nurr1转导增强了这些神经元在膜去极化时产生和释放DA的能力。本研究证明了对ES细胞进行有效的基因操作可促进其向中脑DA神经元分化，它将作为通过关键转录因子对ES细胞进行基因工程以调节其细胞命运的框架。
