Schneebauer Gabriel, Mauracher David, Fiechtner Birgit, Pelster Bernd
Institute of Zoology, Leopold-Franzens-Universität Innsbruck, Technikerstr.25, 6020, Innsbruck, Austria.
Center for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria.
Fish Physiol Biochem. 2018 Apr;44(2):599-613. doi: 10.1007/s10695-017-0456-y. Epub 2018 Jan 11.
The rate of glucose metabolism has been shown to be correlated to glucose uptake in swimbladder gas gland cells. Therefore, it is assumed that in the European eel silvering, i.e., the preparation of the eel for the spawning migration to the Sargasso Sea, coincides with an enhanced capacity for glucose uptake. To test this hypothesis expression of all known glucose transport proteins has been assessed at the transcript level in yellow and in silver eels, and we also included Anguillicola crassus infected swimbladders. Glucose uptake by rete mirabile endothelial cells could be crucial for the countercurrent exchange capacity of the rete. Therefore, this tissue was also included in our analysis. The results revealed expression of ten different members of the slc2 family of glucose transporters, of four slc5 family members, and of kiaa1919 in gas gland tissue. Glucose transporters of the slc2 family were expressed at very high level, and slc2a1b made up about 80% of all slc2 family members, irrespective of the developmental state or the infection status of the eel. Overall, the slc5 family contributed to only about 8% of all detected glucose transport transcripts in gas gland tissue, and the slc2 family to more than 85%. In rete capillaries, the contribution of sodium-dependent glucose transporters was significantly higher, leaving only 66% for the slc2 family of glucose transporters. Neither silvering nor the infection status had a significant effect on the expression of glucose transporters in swimbladder gas gland tissue, suggesting that glucose metabolism of eel gas gland cells may not be related to transcriptional changes of glucose transport proteins.
已表明鳔气腺细胞中的葡萄糖代谢速率与葡萄糖摄取相关。因此，据推测，欧洲鳗鲡的银化现象，即鳗鲡为向马尾藻海进行产卵洄游所做的准备，与葡萄糖摄取能力增强相吻合。为了验证这一假设，我们在转录水平评估了黄鳗和银鳗中所有已知葡萄糖转运蛋白的表达情况，并且我们还纳入了感染粗厚鳗鲡线虫的鳔。奇网内皮细胞对葡萄糖的摄取对于奇网的逆流交换能力可能至关重要。因此，该组织也被纳入我们的分析。结果显示，在气腺组织中，葡萄糖转运蛋白的slc2家族有十个不同成员、slc5家族有四个成员以及kiaa1919有表达。slc2家族的葡萄糖转运蛋白表达水平非常高，且无论鳗鲡的发育状态或感染状况如何，slc2a1b约占所有slc2家族成员的80%。总体而言，在气腺组织中，slc5家族仅占所有检测到的葡萄糖转运转录本的约8%，而slc2家族则超过85%。在 rete 毛细血管中，钠依赖性葡萄糖转运蛋白的贡献显著更高，葡萄糖转运蛋白的slc2家族仅占66%。银化现象和感染状况对鳔气腺组织中葡萄糖转运蛋白的表达均无显著影响，这表明鳗鲡气腺细胞的葡萄糖代谢可能与葡萄糖转运蛋白的转录变化无关。
