Identification of oxygen gas channels involved in gas secretion into the swimbladder

识别参与气体分泌到鱼鳔中的氧气通道

• 批准号: 23657054
• 负责人: KATO Akira
• 金额: $ 2.58万
• 依托单位: Tokyo Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Challenging Exploratory Research
• 财政年份: 2011
• 资助国家: 日本
• 起止时间: 2011 至 无数据
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-23657054/
• 关键词: ガスチャネル; アクアポリン; 鰾; フグゲノム; 乳酸輸送体; グルコース輸送体; ガス腺細胞; 奇網

The gas in the swimbladder of teleost fish is composed primarily of O_2, and the swimbladder volume is regulated by O_2 transfer between the luminal space of the swimbladder and the blood. In the swimbladder, lactic acid generation by anaerobic glycolysis in the gas gland epithelial cells and its recycling through the rete mirabile bundles of countercurrent capillaries are essential for local blood acidification and oxygen liberation from hemoglobin by the "Root effect."To identify genes involved in the local blood acidification, we analyzed the swimbladder of fugu(Takifugu rubripes) by genome database mining, expression analyses, and immunohistochemistry. Gas gland cells contained glycogen, GAPDH, and a gluconeogenesis enzyme FBP1 at high levels, suggesting that a futile cycle consumes ATP and generates heat. In basolateral membrane of gas gland cells, GLUT6 and a cinnamate-insensitive low-affinity/high-conductance lactic acid transporter MCT4b were highly expressed and may mediate glucose uptake and lactic acid secretion, respectively. Acinnamate-sensitive high-affinity lactic acid transporter MCT1b was highly expressed in arterial, but not venous, capillary endothelial cells in rete mirabile and may mediate recycling of lactic acid in rete mirabile. Two aquaporins were expressed in apical membrane of gas gland cells, and may mediate O_2 secretion as gas channels. These results provide new insights for how swimbladder secretes O_2 and inflates under water pressure.

硬骨鱼鳔中的气体主要由O_2组成，鳔体积是通过鳔腔内空间与血液之间的O_2传递来调节的。在鳔中，气腺上皮细胞中无氧糖酵解产生的乳酸及其通过逆流毛细血管的网状奇迹束的再循环对于局部血液酸化和通过“根效应”从血红蛋白中释放氧气至关重要。为了鉴定参与局部血液酸化的基因，我们分析了河​​豚（Takifugu）的鳔。 rubripes）通过基因组数据库挖掘、表达分析和免疫组织化学。气腺细胞含有高水平的糖原、GAPDH 和糖异生酶 FBP1，表明无效循环会消耗 ATP 并产生热量。在气腺细胞的基底外侧膜中，GLUT6 和肉桂酸不敏感的低亲和力/高电导乳酸转运蛋白 MCT4b 高表达，可能分别介导葡萄糖摄取和乳酸分泌。肉桂酸敏感的高亲和力乳酸转运蛋白 MCT1b 在奇迹网的动脉毛细血管内皮细胞中高表达，但在静脉毛细血管内皮细胞中不表达，并且可能介导奇迹网中乳酸的再循环。两种水通道蛋白在气腺细胞顶膜表达，可能作为气体通道介导O_2分泌。这些结果为鳔如何分泌O_2并在水压下膨胀提供了新的见解。

项目成果

Histological demonstration of glucose transporters, fructose-1, 6-bisphosphatase, and glycogen in gas gland cells of the swimbladder : is a metabolic futile cycle operating

鱼鳔气腺细胞中葡萄糖转运蛋白、果糖-1、6-双磷酸酶和糖原的组织学证明：是一个代谢无效循环运行

• DOI: 10.1016/j.bbrc.2011.12.006
• 发表时间: 2012
• 期刊: Biochem Biophys Res Commun
• 作者: Munakata K;Ookata K;Doi H;Baba O;Terashima T;Hirose S;Kato A.
• 通讯作者: Kato A.

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

河豚鳔的气腺细胞正在进行代谢无效循环

• 发表时间: 2011
• 作者: Munakata K;Ookata K;Doi H;Baba O;Terashima T;Hirose S;Kato A.;宗像啓司郎,大方香代子,馬場麻人,土井啓行,広瀬茂久,加藤明
• 通讯作者: 宗像啓司郎,大方香代子,馬場麻人,土井啓行,広瀬茂久,加藤明

海水魚腎臓のCa^<2+>,Mg^<2+>排出を担うイオン輸送体および鰾(うきぶくろ)の酸素ガス充填を担う乳酸輸送体の解析

咸水鱼肾脏中负责Ca^<2+>、Mg^<2+>排泄的离子转运蛋白和鱼泳衣中负责充氧的乳酸转运蛋白的分析

• 发表时间: 2011
• 作者: 加藤明;Islam Zinia;梅澤誉広;御輿真穂;林菜穂子;土井啓行;Min-Hwang Chang;Michael F.Romero;広瀬茂久
• 通讯作者: 広瀬茂久