A biogenic amine and a neuropeptide act identically: tyramine signals through calcium in Drosophila tubule stellate cells.
A biogenic amine and a neuropeptide act identically: tyramine signals through calcium in Drosophila tubule stellate cells.
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DOI：
10.1098/rspb.2012.2943
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发表时间：
2013-04-22
期刊：
影响因子：
--
通讯作者：
Dow JA
中科院分区：
文献类型：
--
作者：
Cabrero P;Richmond L;Nitabach M;Davies SA;Dow JA
昆虫渗透压调节受到高度复杂的内分泌控制。在果蝇中，果蝇激肽和酪胺均作用于马尔皮基（肾）小管星状细胞以激活氯分流电导，从而增加液体产生速率。已知果蝇激肽通过细胞内钙发挥作用，但酪胺的作用方式尚不清楚。在这里，我们使用转基因编码的 GFP::apoaequorin 翻译融合，靶向 GAL4/UAS 控制下的主细胞或星状细胞，以证明酪胺确实可以提高星状细胞中的钙含量，但不能提高主细胞中的钙含量。此外，细胞内钙信号半最大激活的 EC(50) 酪胺浓度与根据先前发表的酪胺诱导的氯离子通量增加的数据计算得出的浓度相同。此外，在NorpA（一种磷脂酶C）和itpr（肌醇三磷酸受体基因）的突变体中，酪胺向钙的信号传导显着减少，我们之前已经证明该基因对于果蝇激肽信号传导是必需的。因此，酪胺和果蝇激肽信号聚集在磷脂酶 C 上，然后聚集在细胞内钙上；两者都通过 itpr 发出信号来增加氯分流电导。为了测试这个模型，我们共同应用了酪胺和果蝇激肽，结果表明钙信号既不是相加的也不是协同的。因此，这两条信号通路代表了不同组织（神经组织和上皮组织）控制肾功能同一方面的平行、独立机制。
Insect osmoregulation is subject to highly sophisticated endocrine control. In Drosophila, both Drosophila kinin and tyramine act on the Malpighian (renal) tubule stellate cell to activate chloride shunt conductance, and so increase the fluid production rate. Drosophila kinin is known to act through intracellular calcium, but the mode of action of tyramine is not known. Here, we used a transgenically encoded GFP::apoaequorin translational fusion, targeted to either principal or stellate cells under GAL4/UAS control, to demonstrate that tyramine indeed acts to raise calcium in stellate, but not principal cells. Furthermore, the EC(50) tyramine concentration for half-maximal activation of the intracellular calcium signal is the same as that calculated from previously published data on tyramine-induced increase in chloride flux. In addition, tyramine signalling to calcium is markedly reduced in mutants of NorpA (a phospholipase C) and itpr, the inositol trisphosphate receptor gene, which we have previously shown to be necessary for Drosophila kinin signalling. Therefore, tyramine and Drosophila kinin signals converge on phospholipase C, and thence on intracellular calcium; and both act to increase chloride shunt conductance by signalling through itpr. To test this model, we co-applied tyramine and Drosophila kinin, and showed that the calcium signals were neither additive nor synergistic. The two signalling pathways thus represent parallel, independent mechanisms for distinct tissues (nervous and epithelial) to control the same aspect of renal function.
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DOI：
10.1152/ajpregu.00584.2001
发表时间：
2002-05-01
影响因子：
2.8
作者：
Kean, L;Cazenave, W;Dow, JAT
通讯作者：
Dow, JAT
影响因子：
30.5
作者：
Kaneko, Takashi;Yano, Tamaki;Silverman, Neal
通讯作者：
Silverman, Neal
影响因子：
5.5
作者：
Blumenthal, EM
通讯作者：
Blumenthal, EM
影响因子：
3.6
作者：
de Haro, Maria;Al-Ramahi, Ismael;Herrero, Pilar
通讯作者：
Herrero, Pilar
影响因子：
3.7
作者：
Chintapalli VR;Terhzaz S;Wang J;Al Bratty M;Watson DG;Herzyk P;Davies SA;Dow JA
通讯作者：
Dow JA