表題番号:2020R-051 日付:2021/03/22
研究課題新規ペントースリン酸経路で働くグルコン酸キナーゼのマウスにおける発現解析
研究者所属(当時) 資格 氏名
(代表者) 人間科学学術院 人間科学部 講師 近藤 嘉高
研究成果概要

Pentose phosphate pathway (PPP) produce NADPH which is utilized for fatty acid synthesis, cholesterol synthesis, and steroid biosynthesis, and redox maintenance, and ribose 5-phosphate which is necessary for synthesis of nucleic acid. It is known that alternative pathway of PPP from glucose to 6-phosphogluconate exists in bacteria, however, it remains unclear in animals. In our previous study, SMP30/gluconolactonase (GNL) hydrolyzed glucono 1,5-lactone to gluconate, and gluconokinase (GNK) catalyzed phosphorylation of gluconate to 6-phosphogluconate in human and mouse. To reveal tissue distribution of GNK in mouse, we measured gene expression levels of GNK, and compared with those of SMP30/GNL, glucose 6-phosphate dehydrogenase (G6PD), and 6-phosphogluconolactonase (6PGL).

Six C57BL/6J male mice were dissected at 8 weeks of age, and 20 kinds of tissues were collected. Gene expression levels of GNK, SMP30/GNL, G6PD, and 6PGL were quantified by using real-time PCR. GNK, SMP30/GNL, G6PD and 6PGL genes were ubiquitously expressed in almost all tissues. GNK gene was highly expressed in liver, kidney, duodenum, and brown fat. Gene expression of SMP30/GNL was most abundant in liver, subsequently in kidney, duodenum, and adrenal gland. G6PD gene was highly expressed in epididymal fat, brown fat, adrenal gland, and testis. 6PGL gene showed higher expression in brown fat and testis.

Overall, tissue distribution of GNK gene expression showed similarity to that of SMP30/GNL, which is distinct from those of G6PD and 6PGL. These results suggest that GNK and SMP30/GNL could cooperatively functions in alternative PPP.