n-3 PUFA biosynthesis by the copepod Apocyclops royi documented using fatty acid profile analysis and gene expression analysis

Biology Open

Lars Hestbjerg Hansen¹  Benni Winding Hansen²  Tue Sparholt Jørgensen²  John Mortensen²  Per Meyer Jepsen²  Bolette Lykke Holm Nielsen²  Louise Gøtterup² 

[1] Aarhus University, Department of Environmental Science, Roskilde DK-4000, Denmark;Roskilde University, Department of Science and Environment, Roskilde DK-4000, Denmark;

关键词: Copepod;    DHA;    Biosynthesis;    Gene expression;    Transcriptome;   

DOI  :  10.1242/bio.038331

来源: DOAJ

【 摘 要 】

The cyclopoid copepod Apocyclops royi (Lindberg 1940) is one of two dominant mesozooplankton species in brackish Taiwanese aquaculture ponds. Periodically low n-3 polyunsaturated fatty acid (PUFA) content in seston could potentially be a limiting factor for zooplankton diversity. Apocyclops royi’s potential ability to biosynthesize n-3 PUFA was investigated through a short-term feeding experiment on four species of microalgae. Furthermore, we analyzed the expression of genes encoding putative fatty acid elongase (ELO) and desaturase (FAD) enzymes in A. royi on long-term diets of the PUFA-poor Dunaliella tertiolecta and the PUFA-rich Isochrysis galbana. The copepods exhibited high contents of docosahexaenoic acid (DHA, C22:6n-3) (>20% of total fatty acid) even when DHA-starved for two generations, and no significant differences were found in absolute DHA content between treatments. Transcripts correlating to the four enzymes Elovl4, Elovl5, Fad Δ5 and Fad Δ6 in the n-3 PUFA biosynthetic pathway were identified. Gene expression analysis revealed a significantly higher expression of two desaturases similar to Fad Δ6 in copepods fed PUFA-lacking algae compared to copepods fed algae with high PUFA content. These findings suggest a highly active n-3 PUFA biosynthesis and capability of DHA production in A. royi when fed low-PUFA diets.

【 授权许可】

Unknown