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Transcriptomic and lipidomic analysis reveal the mechanism of phosphorus-induced lipid class remodeling in Nannochloropsis sp. PJ12

ABSTRACT: Phytoplankton lipids, such as microalgae lipids, are important compounds of increasing interest in bioenergy, food, pharmacy, aquaculture and ecology for their high molecular diversity. There is a taxonomically diverse lipid response under P stress with unresolved questions related to the diversified mechanism behind the lipid responses. A marine microalgae with high EPA content was isolated, named Nannochloropsis sp. PJ12. We reveal a mechanism of phosphorus-induced lipid class remodeling in Nannochloropsis sp. PJ12 based on highly corresponding transcriptome and lipidome data. Phosphorus- deprivation leads to the rapid reduction of phospholipids (PL) and synthesis of the betaine lipids (BL). Phosphorus-complement recovers the content of PL and BL to the original level. The changes are mediated mainly by a glycerophosphoryldiester phosphodiesterases on the transcriptome level. To adapt to low phospholipids, the transcription levels of gene encoding P transporter were upregulated. When Nannochloropsis sp. PJ12 was once again under phosphorus-complement, some of gene encoding P transporter continue to increase on the transcription levels. The novel phospholipid-remodeling scheme opens new avenues for metabolic engineering of lipid composition in algae.

ORGANISM(S): Nannochloropsis sp.

PROVIDER: GSE124501 | GEO | 2021/12/20

REPOSITORIES: GEO

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