Effects of elevated seawater pCO2 on gene expression patterns in the gills of the green crab, Carcinus maenas. Carcinus maenas

In order to promote our understanding of the responses of green crab acid-base regulatory epithelia to high pCO2, Baltic Sea green crabs were exposed to a pCO2 of 400 Pa for 3 and 7 days after which posterior gills 7 and 9 were sampled. Gills were then subsequently screened for differentially expressed gene transcripts using a 4,462-feature microarray developed by Towle et al. 2010. Overall design: For each experimental block (gill7-day3, gill7-day7, gill9-day3, gill9-day7), 6 replicate samples were obtained for control (= 39 Pa) and elevated (= 400 Pa) pCO2 exposed animals. Each microarray slide included 4 technical replicates for each transcript and was hybridized with one control pCO2 (labelled with AlexaFluor555) and one elevated pCO2 cDNA (labelled with AlexaFluor647). Lowess-normalized gene expression was calculated as the log2 of the ratio of the fluorescence intensity of the CO2-treatment cDNA to the fluorescence intensity of the control cDNA (log2 ratio=F635/F532).

为深化对绿蟹酸碱调节上皮组织响应高二氧化碳分压（pCO₂）机制的理解，本研究将波罗的海绿蟹暴露于400 Pa的pCO₂环境中，分别处理3天与7天，随后采集其第7、9对后鳃组织。随后，采用Towle等人2010年开发的搭载4462个探针的微阵列芯片，对鳃组织中的差异表达基因转录本进行筛选。

整体实验设计：针对每个实验单元（gill7-day3、gill7-day7、gill9-day3、gill9-day7），对照组（pCO₂为39 Pa）与高pCO₂（400 Pa）处理组各获取6个生物学重复样本。每张微阵列芯片为每个转录本设置4个技术重复，分别以AlexaFluor555标记对照组pCO₂的cDNA、AlexaFluor647标记高pCO₂处理组的cDNA后进行杂交。采用Lowess标准化法计算基因表达量，具体为CO₂处理组cDNA荧光强度与对照组cDNA荧光强度比值的以2为底的对数（log₂比值=F635/F532）。