|Budget Amount *help
¥2,600,000 (Direct Cost : ¥2,600,000)
Fiscal Year 1999 : ¥1,200,000 (Direct Cost : ¥1,200,000)
Fiscal Year 1998 : ¥1,400,000 (Direct Cost : ¥1,400,000)
Nucleotide pyrophosphatase/phosphodiesterase I is an ecto-enzyme catalyzing a hydrolysis of extracellular ATP, and consists of a three homologous molecules, namely, PC-1, PD-Iα/autotaxin, and PD-Iβ/gp130ィイD1RB14-6ィエD1/B10. We have proposed the nomenclature for these molecules, E-NPP1, -2, and -3, respectively. We have previously reported that E-NPP2 is expressed in neuroblastoma tissues, and its expression level is related to the clinical stage of the patients. We have now shown that E-NPP3 is expressed in glioma cells. We also analyzed the promoter activity of the E-NPP3 gene and determined the region required for cell-type specific transcription of this gene. The mouse carrying a mutation in the E-NPP1 gene shows a phenotype resembling human disease, the ossification of the longitudinal ligament of the spine, indicating that E-NPP1 is involved in the regulation of bone formation. We showed that both E-NPP1 and -3 are expressed in chondrocytes at different subcellular localization. E-NPP1 is mostly localized in the plasma membrane whereas E-NPP3 is localized in the Golji body as well as plasma membrane. Both molecules increased a production of adenosine and pyrophosphate in chondrocytes.