Taira M, Iizasa T, Yamada K, Shimada H, Tatibana M
Department of Biochemistry, Chiba University School of Medicine, Japan.
Biochim Biophys Acta. 1989 Mar 1;1007(2):203-8. doi: 10.1016/0167-4781(89)90040-7.
Cloning of cDNA coding for rat phosphoribosyl pyrophosphate (PPRibP) synthetase (EC 2.7.6.1) revealed two distinct types of subunit, referred to as PRS I and PRS II (Taira et al. (1987) J. Biol. Chem. 262, 14867-14870). Tissue-specific expression of PRS I and PRS II genes (designated PRPS1 and PRPS2, respectively), was shown for 16 rat organs, using Northern blot analysis. The 2.3 kb PRPS1 mRNA level was high in the brain and adrenal gland, whereas the 3.7 kb PRPS2 mRNA level prevailed in the lung and spleen. Both genes were highly expressed in the thymus, adipose tissue and testis. In other mammals (mouse, calf and human), these two types of mRNA were also detected in various tissues and cell lines. Thus, the expression of each gene is regulated in a tissue-specific manner and there may be functional differences between catalytic and/or regulatory properties of subunits PRS I and II of this enzyme. In the testis, an additional PRPS1-related transcript of 1.4 kb was noted in rats, mice and humans. This transcript may belong to a group of testis-specific gene expressions or functions.
编码大鼠磷酸核糖焦磷酸（PPRibP）合成酶（EC 2.7.6.1）的cDNA克隆揭示了两种不同类型的亚基，分别称为PRS I和PRS II（Taira等人（1987年）《生物化学杂志》262卷，14867 - 14870页）。使用Northern印迹分析，显示了16种大鼠器官中PRS I和PRS II基因（分别命名为PRPS1和PRPS2）的组织特异性表达。2.3 kb的PRPS1 mRNA水平在脑和肾上腺中较高，而3.7 kb的PRPS2 mRNA水平在肺和脾中占主导。这两个基因在胸腺、脂肪组织和睾丸中均高度表达。在其他哺乳动物（小鼠、小牛和人类）中，这两种类型的mRNA也在各种组织和细胞系中被检测到。因此，每个基因的表达以组织特异性方式受到调节，并且该酶的亚基PRS I和II在催化和/或调节特性之间可能存在功能差异。在睾丸中，在大鼠、小鼠和人类中均发现了一个额外的1.4 kb的与PRPS1相关的转录本。该转录本可能属于一组睾丸特异性基因表达或功能。
