Transcriptomic analysis of thermally stressed Symbiodinium reveals differential expression of stress and metabolism genes

Chapter 2 of the author’s PhD thesis is published in the journal Frontiers in Plant Science. This study describes the transcriptome response of Symbiodinium sp. (clade F) cultures exposed to thermal stress (four, nineteen and twenty-eight days) at future temperature conditions and is linked with physiological changes observed. Within the differentially expressed genes, transcripts with significance to the stress response of Symbiodinium were detected. The results indicate a shift in metabolism, from carbon fixation to fatty acid catabolism, supported by upregulation of β-oxidation, glyoxylate cycle and gluconeogenic enzymes, this to our knowledge, has not previously been reported in Symbiodinium. The implications of altered metabolic processes from exposure to thermal stress found in this study, on coral – Symbiodinium associations has not been explored. This study provides an important reference for understanding the mechanisms of coral bleaching at future temperature conditions. The Illumina sequenced read data reported in this article have been deposited into the National Center for Biotechnology Information (NCBI) Sequence Read Archive under the accession number SRA467551, which is associated with BioProject number PRJNA342240. The associated analysed data included as appendices of this thesis may be found in the supplementary information of the publication or attached as MS Excel sheets.

作者的博士论文第2章已发表于《Frontiers in Plant Science》（植物科学前沿）期刊。本研究针对未来升温情景下经热胁迫处理（分别为4天、19天与28天）的Symbiodinium sp.（F分支，虫黄藻属）培养物的转录组响应展开分析，并将其与观测到的生理变化建立关联。在差异表达基因中，本研究检测到了与虫黄藻胁迫响应紧密相关的转录本。研究结果表明，虫黄藻的代谢模式发生了从碳固定到脂肪酸分解的转变，该转变伴随β-氧化、乙醛酸循环及糖异生相关酶的上调表达；据我们所知，这一现象此前从未在虫黄藻中被报道过。本研究发现的热胁迫诱导代谢过程改变，其对珊瑚-虫黄藻共生体系的影响尚未得到探索。本研究为理解未来升温情景下的珊瑚白化机制提供了重要参考依据。本文所报道的Illumina测序读段数据已提交至美国国家生物技术信息中心（National Center for Biotechnology Information, NCBI）的序列读段档案库（Sequence Read Archive, SRA），登录编号为SRA467551，关联的生物项目编号为PRJNA342240。本论文附录中收录的相关分析数据，可在该发表文章的补充材料中获取，或以MS Excel表格附件的形式查阅。