Department of Biology, University of Pennsylvania, Philadelphia, PA, 19104, USA.
Marine Biology Department, Centre Scientifique de Monaco, 8 Quai Antoine 1(er), MC-98000, Monaco, Monaco.
Biochem Biophys Res Commun. 2020 May 7;525(3):576-580. doi: 10.1016/j.bbrc.2020.02.115. Epub 2020 Feb 27.
Coral calcification is intricately linked to the chemical composition of the fluid in the extracellular calcifying medium (ECM), which is situated between the calcifying cells and the skeleton. Here we demonstrate that the acid-base sensing enzyme soluble adenylyl cyclase (sAC) is expressed in calcifying cells of the coral Stylophora pistillata. Furthermore, pharmacological inhibition of sAC in coral microcolonies resulted in acidification of the ECM as estimated by the pH-sensitive ratiometric indicator SNARF, and decreased calcification rates, as estimated by calcein labeling of crystal growth. These results indicate that sAC activity modulates some of the molecular machinery involved in producing the coral skeleton, which could include ion-transporting proteins and vesicular transport. To our knowledge this is the first study to directly demonstrate biological regulation of the alkaline pH of the coral ECM and its correlation with calcification.
珊瑚钙化与细胞外钙化介质（ECM）中流体的化学成分密切相关，ECM 位于钙化细胞和骨骼之间。在这里，我们证明了酸碱性感应酶可溶性腺苷酸环化酶（sAC）在珊瑚 Stylophora pistillata 的钙化细胞中表达。此外，珊瑚微群体中 sAC 的药理学抑制导致 ECM 酸化，如 pH 敏感比率指示剂 SNARF 所估计的那样，并且钙化率降低，如晶体生长的 calcein 标记所估计的那样。这些结果表明，sAC 活性调节了参与产生珊瑚骨骼的一些分子机制，其中可能包括离子转运蛋白和囊泡运输。据我们所知，这是第一项直接证明珊瑚 ECM 的碱性 pH 值的生物学调节及其与钙化相关的研究。
