By 2100, global warming is predicted to significantly reduce the capacity of marine primary producers for long-chain polyunsaturated fatty acid (LC-PUFA) synthesis. Primary consumers such as harpacticoid copepods (Crustacea) might mitigate the resulting adverse effects on the food web by increased LC-PUFA bioconversion. Here, we present a high-quality de novo transcriptome assembly of the copepod Platychelipus littoralis , exposed to changes in both temperature (+3°C) and dietary LC-PUFA availability. Using this transcriptome, we detected multiple transcripts putatively coding for LC-PUFA-bioconverting front-end fatty acid (FA) desaturases and elongases, and performed phylogenetic analyses to identify their relationship with sequences of other (crustacean) taxa. While temperature affected the absolute FA concentrations in copepods, LC-PUFA levels remained unaltered even when copepods were fed an LC-PUFA-deficient diet. While this suggests plasticity of LC-PUFA bioconversion within P. littoralis , none of the putative front-end desaturase or elongase transcripts was differentially expressed under the applied treatments. Nevertheless, the transcriptome presented here provides a sound basis for future ecophysiological research on harpacticoid copepods. This article is part of the theme issue ‘The next horizons for lipids as ‘trophic biomarkers’: evidence and significance of consumer modification of dietary fatty acids'.

中文翻译：

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变化环境中 harpacticoid 桡足类的脂肪酸生物转化：转录组学方法

到 2100 年，全球变暖预计将显着降低海洋初级生产者合成长链多不饱和脂肪酸 (LC-PUFA) 的能力。主要消费者，如 harpacticoid 桡足类动物（甲壳纲动物），可能会通过增加 LC-PUFA 生物转化来减轻对食物网造成的不利影响。在这里，我们展示了桡足类的高质量从头转录组组装滨鸭，暴露于温度 (+3°C) 和膳食 LC-PUFA 可用性的变化。使用该转录组，我们检测到了可能编码 LC-PUFA 生物转化前端脂肪酸 (FA) 去饱和酶和延伸酶的多个转录本，并进行了系统发育分析，以确定它们与其他（甲壳类）类群序列的关系。虽然温度影响桡足类的绝对 FA 浓度，但即使给桡足类喂食缺乏 LC-PUFA 的饮食，LC-PUFA 水平也保持不变。虽然这表明 LC-PUFA 生物转化的可塑性北滨松，在所应用的处理下，假定的前端去饱和酶或延伸酶转录物均未差异表达。尽管如此，这里提出的转录组为今后对 harpacticoid 桡足类动物的生态生理学研究提供了良好的基础。本文是主题“脂质作为‘营养生物标志物’的下一个前景：消费者改变膳食脂肪酸的证据和意义”的一部分。