A metabolic futile cycle is operating in gas gland cells of the swimbladder.

Research Project

Project/Area Number	24657085
Research Category	Grant-in-Aid for Challenging Exploratory Research
Allocation Type	Multi-year Fund
Research Field	Functional biochemistry
Research Institution	Tokyo Institute of Technology
Principal Investigator	HIROSE Shigehisa 東京工業大学, 大学院・生命理工学研究科, 教授 (10134199)
Project Period (FY)	2012
Project Status	Completed (Fiscal Year 2012)
Budget Amount *help	¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000) Fiscal Year 2012: ¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000)
Keywords	酵素の調節 / 代謝調節 / ルート効果ヘモグロビン / 解糖系 / 乳酸輸送体 / Fructose bisphosphatase / 空転サイクル / 熱発生 / 対向流血管系 / ガス腺
Research Abstract	H+/monocarboxylate transporters MCT1b and MCT4b were found to be highly expressed in the fugu swimbladder. Immunohistochemical analyses of metabolic enzymes demonstrated that a gluconeogenesis enzyme fructose-1,6-bisphosphatase (Fbp1) and a glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (Gapdh) are highly expressed in gas gland cells. The simultaneous catalyses of glycolysis and gluconeogenesis reactions suggest the presence of a futile cycle in gas gland cells to maintain the levels of ATP low and to generate heat that helps reduce the solubility of O2