Dabernat S, Larou M, Massé K, Hökfelt T, Mayer G, Daniel J Y, Landry M
Laboratoire de Biologie de la Différenciation et du Développement, Université Bordeaux 2, 146, rue Léo Saignat, 33 076, Bordeaux Cedex,
Brain Res Mol Brain Res. 1999 Jan 8;63(2):351-65. doi: 10.1016/s0169-328x(98)00300-3.
Nm23 has been identified as a gene family encoding different isoforms of the nucleoside diphosphate kinase. This protein is a key enzyme in the control of cellular concentrations of nucleoside triphosphates. Moreover, it has been shown to play important roles in various cellular functions such as differentiation and metastasis. In the present study, a second cDNA for nucleoside diphosphate kinase A (Nm23-M1) was isolated from a cDNA library of mouse embryonic stem cells. This clone encodes the same putative 152 aminoacids long protein as an already published cDNA but is longer in both its 5' and 3' untranslated regions. Tissue and cellular distribution of nm23-M1 mRNA was investigated by using Northern blot analysis and in situ hybridization. Nm23-M1 transcripts were found to be widely distributed throughout the mouse central nervous system with prominent expression in several restricted areas. No differences were noticed between the distribution of long and short transcripts. Furthermore, a similar pattern of expression was described in the central nervous system for nm23-M2 mRNA, encoding a second isoform of the nucleoside diphosphate kinase. However, the transcript of this isoform displayed a wider distribution and was expressed in all organs analysed by northern blotting. The possible involvement of nm23-M1 in differentiation of mouse nervous system is further discussed.
Nm23已被鉴定为一个基因家族，编码核苷二磷酸激酶的不同亚型。该蛋白是控制细胞内核苷三磷酸浓度的关键酶。此外，它已被证明在诸如分化和转移等各种细胞功能中发挥重要作用。在本研究中，从小鼠胚胎干细胞的cDNA文库中分离出核苷二磷酸激酶A（Nm23-M1）的第二个cDNA。该克隆编码的假定蛋白质与已发表的cDNA编码的蛋白质相同，长度均为152个氨基酸，但在其5'和3'非翻译区更长。通过Northern印迹分析和原位杂交研究了nm23-M1 mRNA的组织和细胞分布。发现Nm23-M1转录本广泛分布于整个小鼠中枢神经系统，在几个特定区域有显著表达。长转录本和短转录本的分布之间未发现差异。此外，在中枢神经系统中，编码核苷二磷酸激酶第二种亚型的nm23-M2 mRNA也呈现出类似的表达模式。然而，该亚型的转录本分布更广泛，通过Northern印迹分析在所有分析的器官中均有表达。进一步讨论了nm23-M1在小鼠神经系统分化中的可能作用。
