Weiner J A, Chun J
Department of Pharmacology, School of Medicine, University of California, San Diego, La Jolla 92093-0636, USA.
J Comp Neurol. 1997 May 5;381(2):130-42. doi: 10.1002/(sici)1096-9861(19970505)381:2<130::aid-cne2>3.0.co;2-4.
To identify genes associated with early postmitotic cortical neurons, gene fragments were examined for expression in postmitotic, but not proliferative, zones of the embryonic murine cortex. Through this approach, a novel member of the zinc finger gene family, containing 6 C2HC fingers, was isolated and named postmitotic neural gene-1, or png-1. Embryonic png-1 expression was: 1) nervous system-specific; 2) restricted to zones containing postmitotic neurons; and 3) detected in all developing neural structures examined. In the cortex, png-1 expression was first observed on embryonic day 11, correlating temporally and spatially with the known generation of the first cortical neurons. Gradients of png-1 expression throughout the embryonic central nervous system further correlated temporally and spatially with known gradients of neuron production. With development, expression remained restricted to postmitotic zones, including those containing newly-postmitotic neurons. Png-1 was also detected within two days of neural retinoic acid induction in P19 cells, and expression increased with further neuronal differentiation. These data implicate png-1 as one of the earliest molecular markers for postmitotic neuronal regions and suggest a function as a panneural transcription factor associated with neuronal differentiation.
为了鉴定与有丝分裂后早期皮质神经元相关的基因，研究人员检测了基因片段在胚胎小鼠皮质有丝分裂后而非增殖区的表达情况。通过这种方法，分离出了锌指基因家族的一个新成员，它含有6个C2HC锌指结构，并被命名为有丝分裂后神经基因-1（png-1）。胚胎期png-1的表达具有以下特点：1）具有神经系统特异性；2）局限于含有有丝分裂后神经元的区域；3）在所检测的所有发育中的神经结构中均能检测到。在皮质中，png-1的表达最早在胚胎第11天被观察到，在时间和空间上与已知的第一批皮质神经元的产生相关。整个胚胎中枢神经系统中png-1表达的梯度在时间和空间上也与已知的神经元产生梯度相关。随着发育，表达仍局限于有丝分裂后区域，包括含有新有丝分裂后神经元的区域。在P19细胞中，神经视黄酸诱导后两天内也检测到了png-1，并且随着神经元的进一步分化表达增加。这些数据表明png-1是有丝分裂后神经元区域最早的分子标记之一，并提示其作为与神经元分化相关的泛神经转录因子的功能。
