Pendeville Hélène, Peers Bernard, Kas Koen, Voz Marianne L
Laboratoire de Biologie Moléculaire et Génie Génétique, Center for Biomedical Integrated Genoproteomics, University of Liège, B6 4000 Liège (Sart-Tilman), Belgium.
Gene Expr Patterns. 2006 Mar;6(3):267-76. doi: 10.1016/j.modgep.2005.08.001. Epub 2005 Dec 27.
PLAG transcription factors play important roles in oncogenesis. To date three members of this subfamily of zinc finger proteins have been identified in humans and mice: PLAG1, PLAGL1 and PLAGL2. In this study, we identified zebrafish orthologs of PLAG1 and PLAGL2 and a novel member of this family, PLAGX. We examined the temporal expression of these three genes by quantitative real time RT-PCR and found that all three genes are maternally provided, expressed at low level during early somitogenesis and, during late somitogenesis and beyond, PLAG expression increases to reach a plateau level around 5 dpf. Whole mount in situ experiments revealed that PLAG1, PLAGL2 and PLAGX display a similar pattern of expression characterized by a low ubiquitous expression overcame by high expression in some restricted compartments such as the ventricular zone of the brain, the pectoral fin buds, the developing pharyngeal arches and the axial vasculature. We show that this pattern resembles the one observed for the proliferative marker PCNA, suggesting that the PLAG genes are expressed more strongly in zones of active proliferation. This hypothesis was proven for the ventricular zone shown to be a highly proliferative zone using the anti-phosphohistone H3 antibody that detects cells in mitosis.
PLAG转录因子在肿瘤发生过程中发挥着重要作用。迄今为止，在人类和小鼠中已鉴定出该锌指蛋白亚家族的三个成员：PLAG1、PLAGL1和PLAGL2。在本研究中，我们鉴定出了PLAG1和PLAGL2的斑马鱼直系同源物以及该家族的一个新成员PLAGX。我们通过定量实时RT-PCR检测了这三个基因的时序表达，发现这三个基因均由母体提供，在早期体节形成期间表达水平较低，而在晚期体节形成及之后，PLAG表达增加，在5 dpf左右达到平台期水平。整体原位实验表明，PLAG1、PLAGL2和PLAGX呈现出相似的表达模式，其特征是在一些特定区域（如脑室区、胸鳍芽、发育中的咽弓和轴向脉管系统）中，低水平的普遍表达被高水平表达所取代。我们发现这种模式与增殖标记物PCNA所观察到的模式相似，这表明PLAG基因在活跃增殖区域表达更强。使用检测有丝分裂细胞的抗磷酸化组蛋白H3抗体，对脑室区这一高度增殖区域进行检测，证实了这一假设。
