| Project/Area Number |
05670156
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
Pathological medical chemistry
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| Research Institution | Osaka Bioscience Institute |
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Principal Investigator |
WATANABE Kikuko Osaka Bioscience Institute Department of Molecular Behavioral biology, Researcher, 第2研究部, 研究員 (90211672)
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| Co-Investigator(Kenkyū-buntansha) |
SUZUKI Toshiko Osaka Bioscience Institute, Technician, 第2研究部, 研究助手
ENDO Kazuo Kyoto University, 大学院博士課程
HAYAISHI Osamu Osaka Bioscience Institute, Director, 所長 (40025507)
福井 基成 京都大学, 医学部, 医員
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| Project Period (FY) |
1993 – 1995
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| Project Status |
Completed (Fiscal Year 1995)
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| Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1995: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1994: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 1993: ¥800,000 (Direct Cost: ¥800,000)
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| Keywords | prostaglandin (PG) F / PGF synthase / lung / interstitial cell / hypoxia / uterus / プロスタグランジンF / プロスタグランジン / 酵素学 / 遺伝子操作 / 部位特異的変異 / 活性部位 / アルド・ケト還元酵素 / 多機能酵素 |
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| Research Abstract |
Prostaglandin (PG) F synthase is a monomeric protein, consisting of a 322-amino acid polypeptide with a Mr of 36,517 (1). PGF synthase has at least two isozymes of the lung and the liver types, and its primary structure shows high similarity with those of aldose and aldehyde reductases. These enzymes also present dual function which is the reduction of PGD_2 and PGH_2, and may show different biological activities on various tissues. To analyze the structure and biological function of dual function enzymes, we report PGF synthase on enzymatic properties, protein chemistry and immnological properties.
1. The analysis on the structure of PGF synthase.
(a) point mutation (i) "H48L mutant" The enzymatic activity was rapidly inactive for enzyme reaction. (ii) "Y5F mutant" PGD and H reductase activities were hardly detected. (iii) "H117N mutant" PGD reductase activity was not detected, and PGH reductase activity remained to 17%. (b) the role of C-terminal amino acid residues. (i) "deletion of 7
… More
amino acid residues from C-terminus." PGD reductase activity remained to 20% and PGH reductase activity to 80%. (ii) "deletion of 15 amino acid residues from C-terminus." PGD and H reductase activities remained only 5%. ^<55>Tyr seems to be the active site of the reduction of PGD and H,^<117>His may be also localized near its active site, and ^<48>His is related to its active site. Moreover, the result of H117N mutant and that of the deletion of 7 amino acid residues suggest that the binding sites of PGD is different from that of PGH,and that C-terminal amino acid residues need to keep the tertially structure of both active sites.
2. The analysis of functio of PGF synthase
PGF synthase activity shows the highest in lung, and was localized in alveola interstitial cells and nonciliated epithelial cells in lung. Furthermore, by double immunofluorescence staining, anti-PGF synthase antibody labeled for cytoplasmic actin but not for a-smooth muscle actin suggesting that the PGF synthase-positive cells are "contractile interstitial cells (CICs)". These CICs is involved in hypoxic pulmonary vasoconstriction, and PGF synthase may be related to hypoxic pulmonary vasoconstriction.
The expression of PGF synthase in the uterus increased at the late pregnancy at the diestrus. PGF production changes at the estrous cycle and increases at the term of pregnancy accompanied with the expression of uterine PGF synthase. Less
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