CO_(2)升高对风信子鹿角珊瑚(Acropora hyacinthus)钙化速率和 基因表达的影响

Effects of ocean acidification on the calcification and gene expression in coral Acropora hyacinthus

本文以风信子鹿角珊瑚(Acropora hyacinthus)为研究对象,以三亚珊瑚礁海域自然海水培养的珊瑚样本为对照组,模拟本世纪末海水酸化状况,并开展珊瑚模拟培养试验。以此探究海水酸化对A.hyacinthus钙化和基因表达的影响。在酸化胁迫下,A.hyacinthus净钙化速率显著下降,基因表达受到显著影响,其中有机物运输、阴离子运输、化学应激等通路上调,动物器官发育、脂质转运、细胞生物合成、细胞表面受体信号等通路下调。与钙化相关的基因中,碳酸酐酶和溶质运载蛋白下调,但是Ca^(2+)-ATP酶和钙离子运输相关的基因上调。结果表明,高CO_(2)影响了A.hyacinthus的钙化和多个生物过程的基因表达,海水酸化可能通过抑制珊瑚碳酸酐酶等基因表达,减少HCO–3运输,最终降低钙化速率。

We studied the responses of coral Acropora hyacinthus to the increase of CO_(2),with a simulated experiment in which corals were cultured in natural seawater as the control group with pCO2 of 565μatm and in high CO_(2) treatment with pCO_(2) of 1135μatm.The effects of seawater acidification on the calcification and gene expression were investigated.The results showed that under acidification stress,the calcification rate of A.hyacinthus significantly decreased,and the gene expression was greatly affected.As the pathways of organic matter transport,anion transport,chemical stress were up-regulated,and animal organ development,lipid transport,cell biosynthesis,cell surface receptor signal and other pathways were down-regulated.Among the calcification related genes,carbonic anhydrase was down-regulated,and Ca^(2+)-ATPase and calcium ion transport related genes were up-regulated.This experiment showed that high CO_(2 )significantly affected the calcification and gene expression of A.hyacinthus,in which the decrease of calcification-was mainly due to the down-regulation of carbonic anhydrase resulting in the decrease of HCO_(3)^(-).