Signalling of excretory transport proteins in the kidney

人和动物接触到许多环境毒素（重金属、杀虫剂），这些毒素也会影响新陈代谢和蛋白质的运输。我们最近的研究表明，abc出口泵（p -糖蛋白、Bcrp、Mrp2、Mrp4等）的功能和表达也发生了改变。模型鳉鱼（Fundulus heteroclitus）在近端肾小管中表达这些转运蛋白，与人类的转运蛋白非常相似。我们研究了这些转运体的功能和信号级联，例如镉和汞盐的影响。这些盐导致转运蛋白功能降低。初步实验表明，锌盐具有完全相反的作用——增加了鳉鱼小管中ABC转运蛋白的功能。在这里，我们想澄清信号级联。最初的研究表明，最初的Ca2+流入小管细胞，通过内皮素受体B、no合成酶、蛋白激酶C、鞘氨醇激酶、鞘氨醇激酶受体、磷脂酰亚脂-3激酶、Akt触发信号级联，直到mTOR。通过abc转运体的特定荧光底物的动力学实验和该信号通路单一组分的调节剂（激动剂（拮抗剂、抑制剂））的使用，我们旨在验证我们的假设。这些实验将于2016年夏季在美国缅因州的Mount Desert Island生物实验室进行，为期4周。此外，我们计划通过Western-Blot和PCR来研究，是否长期暴露在小管中Zn²+也会导致转运蛋白的表达增加。

Man and Animal are exposed to many environmental toxins (heavy metals, pesticides), which also influence metabolism and transport proteins. Our recent studies show that also ABC-exportpumps (P-Glycoprotein, Bcrp, Mrp2, Mrp4,) are modified in their function and expression. The model spezies Killifish (Fundulus heteroclitus) expresses in proximal kidney tubules these transporters, which are very similar to those found in man. We studied function and Signalling cascades of these transporters, e.g. influence of Cadmium- and Mercury- salts. These salts resulted in a reduced transporter function. Preliminary experiments show that Zinc-salts have exactly the opposite effect - increased function of ABC transporters in Killifish tubules. Here , we want to clarify the signalling cascade. First studies suggest and initial Ca2+ influx into tubular cells, triggering a signal cascade via the Endothelinrezeptor B, NO-Synthase, Proteinkinase C, Sphingosinkinase, Sphingosinkinasereceptor, Phosphatidylinositid-3-Kinase, Akt, until mTOR. By kinetic experiments with specific fluorescent substrates of the ABC-transporters and use of modulators of the single components of this signalling pathway (agonists(antagonists, inhibitors) we aim to verify our assumptions. These experiments will be performed in summer 2016 during 4 weeks at the Mount Desert Island Biological Laboratory, Maine, USA. Furtheron, it is planned by Western-Blot and PCR to study , geprüft werden, whether long term Zn²+-Exposition of the tubuli also results in an increased expression of the transporters.