tailieunhanh - Báo cáo khoa học: Genomic structure, promoter analysis and functional mutation

Aquaporin adipose (AQPap), which we identi®ed from human adipose tissue, is a glycerol channel in adipocyte [Kishida et al. (2000) J. Biol. , 20896±20902]. In the current study, we determined the genomic structure of the human AQPap gene, and identi®ed three AQPap-like genes that resembled ( 95%)AQPap, with little expression in human tissues. | Eur. J. Biochem. 269 1814-1826 2002 FEBS 2002 doi Human aquaporin adipose AQPap gene Genomic structure promoter analysis and functional mutation Hidehiko Kondo1 Iichiro Shimomura1 Ken Kishida1 Hiroshi Kuriyama1 Yasunaka Makino2 Hitoshi Nishizawa1 Morihiro Matsuda1 Norikazu Maeda1 Hiroyuki Nagaretani1 Shinji Kihara1 Yoshihisa Kurachi2 Tadashi Nakamura1 Tohru Funahashi1 and Yuji Matsuzawa1 1 Department of Internal Medicine and Molecular Science Graduate School of Medicine Department of Pharmacology II and 2Graduate School of Medicine Osaka University Yamadaoka Suita Japan Aquaporin adipose AQPap which we identihed from human adipose tissue is a glycerol channel in adipocyte Kishida et al. 2000 J. Biol. Chem. 275 20896-20902 . In the current study we determined the genomic structure of the human AQPap gene and identihed three AQPap-like genes that resembled w 95 AQPap with little expression in human tissues. The AQPap promoter contained a putative peroxisome proliferator response element PPRE at -46 to -62 and a putative insulin response element IRE at -542 -536. Deletion of the PPRE abolished the pioglita-zone-mediated induction of AQPap promoter activity in 3T3-L1 adipocytes. Deletion and single base pair substitution analysis of the IRE abolished the insulin-mediated suppression of the human AQPap gene. Analysis of AQPap sequence in human subjects revealed three missense mutations R12C V59L and G264V and two silent mutations A103A and G250G . The cRNA injection of the missense mutants into Xenopus oocytes revealed the absence of the activity to transport glycerol and water in the AQPap-G264V protein. In the subject homozygous for AQPap-G264V exercise-induced increase in plasma glycerol was not observed in spite of the increased plasma noradrenaline. We suggest that AQPap is responsible for the increase of plasma glycerol during exercise in humans. Keywords mutation aquaporin adipose genome glycerol channel promoter. In response to .