Abstract：
Sperm-specific cation channel (CatSper), sperm-specific Na + /H + exchanger (sNHE), and soluble adenylyl cyclase (sAC) are necessary in the signaling pathways to control sperm motility in many animals, whereas some animals have lost some or all of them. In the present study, we examined CatSper-uninvolved signaling for vigorous undulation of the undulating membrane that is attached to the sperm tail and gives thrust for forward motility in the internally fertilizing newt Cynops pyrrhogaster. Reverse-transcription PCR failed to detect sNHE in the newt sperm. However, the pH of sperm cytoplasm was raised under a high extracellular pH equivalent to that of egg jelly, where sperm motility is initiated by sperm motility-initiating substance (SMIS). Carbonic anhydrase XII/ XVI and SLC4A4/8 were suggested to be present in the sperm, and transported bicarbonates raised the intracellular pH. In egg jelly extract that contained SMIS, the anion transporter inhibitor DIDS weakened the undulation of the undulating membrane, while bicarbonates enhanced it. The cyclic AMP concentration was found to increase in sperm cytoplasm in the egg-jelly extract. An inhibitor of sAC (KH7) weakened the undulation of the undulating membrane, and dibutyryl cyclic AMP blocked the inhibitory effect. Inhibitor of transmembrane AC (DDA) limitedly affected the undulation. The undulation was weakened by an inhibitor of protein kinase A (H89), and by an inhibitor of transient receptor potential (TRP) channels (RN1747). Our results support the conclusions that the high pH of the egg jelly triggers a signaling pathway through sAC, PKA, and TRP channels, and coacts with SMIS to induce forward sperm motility.
摘要：
精子特异性阳离子通道（CatSper），精子特异性Na+/H+交换剂（sNHE），和可溶性腺苷酸环化酶（sAC）是必需的信号通路，以控制许多动物的精子运动，而有些动物失去了部分或全部。在本研究中,我们检查了CatSper未参与的信号，以观察附着在精子尾巴上的起伏膜的剧烈起伏，并为内部受精的newCynopspyrhogaster提供了向前运动的推力。逆转录PCR未能在new精子中检测到sNHE。然而,精子细胞浆的pH值升高到与蛋冻相当的高细胞外pH值，其中精子运动是由精子运动启动物质（SMIS）启动的。建议碳酸酐酶XII/XVI和SLC4A4/8存在于精子中，运输的碳酸氢盐提高了细胞内的pH值。在含有SMIS的蛋冻提取物中，阴离子转运蛋白抑制剂DIDS削弱了起伏膜的起伏，而碳酸氢盐增强了它。发现卵果冻提取物中的精子细胞质中的循环AMP浓度增加。sAC（KH7）的抑制剂削弱了起伏膜的起伏，二丁酰基环AMP阻断了抑制作用。跨膜AC（DDA）抑制剂有限地影响了起伏。蛋白激酶A（H89）的抑制剂削弱了起伏，和瞬时受体电位（TRP）通道（RN1747）的抑制剂。我们的结果支持以下结论：蛋冻的高pH值通过sAC触发信号通路，PKA,和TRP频道，并与SMIS共同诱导前向精子运动。
