Changes in Genome-Wide Methylation and Gene Expression in Response to Future pCO2 Extremes in the Antarctic Pteropod Limacina helicina antarctica
Changes in Genome-Wide Methylation and Gene Expression in Response to Future pCO2 Extremes in the Antarctic Pteropod Limacina helicina antarctica
复制标题
南极翼足类Limacina helicina anarctica全基因组甲基化和基因表达对未来极端pCO2的响应变化
DOI：
10.3389/fmars.2019.00788
复制
发表时间：
2020-01-22
影响因子：
3.7
通讯作者：
Hofmann, Gretchen E.
中科院分区：
文献类型：
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作者：
Bogan, Samuel N.;Johnson, Kevin M.;Hofmann, Gretchen E.
表观遗传过程，如DNA甲基化的变化可能会促进表型可塑性和物种对环境变化的快速适应。生物体对当前和未来极端气候的表观遗传反应程度可能会影响其适应或适应生态而非进化时间尺度上全球变化的能力。翼足类动物螺是南大洋特有的一种丰富的大型浮游动物，被认为是海洋酸化的领头羊，因为它对碳酸盐化学的变化非常敏感。在这项研究中，我们量化了不同海洋酸化制度下DNA甲基化和基因表达随时间的变化。我们暴露了L。在测量全球DNA甲基化和对来自每个处理的动物的转录组进行测序之前，将南极螺旋藻的pCO（2）水平模拟到目前在南大洋沿海的255 matm pCO（2）的标准、目前530 matm pCO（2）的极端和918 matm pCO（2）的预计极端，持续长达7天。L.在暴露于918 martmpCO（2）1天后，螺旋藻显著降低了DNA甲基化29-56%，6天后DNA甲基化恢复到对照水平。此外，L.与复制当前pCO（2）极端值的培养物相比，暴露于918 martmpCO（2）的螺旋藻表现出明显更多的差异表达。差异表达的转录本主要下调。此外，下调的基因富含基因体甲基化的特征。这些发现支持了DNA甲基化在调节L.南极螺旋藻对未来海洋酸化的影响以及pCO（2）的原位变化在季节性或垂直迁移期间经历。更广泛地说，L。尽管在未来pCO（2）水平上，几乎没有证据表明该物种的代谢补偿或细胞应激反应的恢复，但螺旋藻能够对海洋酸化产生实质性的表观遗传反应。
Epigenetic processes such as variation in DNA methylation may promote phenotypic plasticity and the rapid acclimatization of species to environmental change. The extent to which an organism can mount an epigenetic response to current and future climate extremes may influence its capacity to acclimatize or adapt to global change on ecological rather than evolutionary time scales. The thecosome pteropod Limacina helicina antarctica is an abundant macrozooplankton endemic to the Southern Ocean and is considered a bellwether of ocean acidification as it is highly sensitive to variation in carbonate chemistry. In this study, we quantified variation in DNA methylation and gene expression over time across different ocean acidification regimes. We exposed L. helicina antarctica to pCO(2) levels mimicking present-day norms in the coastal Southern Ocean of 255 matm pCO(2), present-day extremes of 530 matm pCO(2), and projected extremes of 918 matm pCO(2) for up to 7 days before measuring global DNA methylation and sequencing transcriptomes in animals from each treatment across time. L. helicina antarctica significantly reduced DNA methylation by 29-56% after 1 day of exposure to 918 matm pCO(2) before DNA methylation returned to control levels after 6 days. In addition, L. helicina antarctica exposed to 918 matm pCO(2) exhibited drastically more differential expression compared to cultures replicating present-day pCO(2) extremes. Differentially expressed transcripts were predominantly downregulated. Furthermore, downregulated genes were enriched with signatures of gene body methylation. These findings support the potential role of DNA methylation in regulating transcriptomic responses by L. helicina antarctica to future ocean acidification and in situ variation in pCO(2) experienced seasonally or during vertical migration. More broadly, L. helicina antarctica was capable of mounting a substantial epigenetic response to ocean acidification despite little evidence of metabolic compensation or recovery of the cellular stress response in this species at future pCO(2) levels.