Comparative analyses of lipidomes and transcriptomes reveal a concerted action of multiple defensive systems against photooxidative stress in Haematococcus pluvialis
© The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.
Veröffentlicht in: | Journal of experimental botany. - 1985. - 65(2014), 15 vom: 20. Aug., Seite 4317-34 |
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1. Verfasser: | |
Weitere Verfasser: | , , , , , , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2014
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Zugriff auf das übergeordnete Werk: | Journal of experimental botany |
Schlagworte: | Comparative Study Journal Article Research Support, Non-U.S. Gov't Astaxanthin high irradiance lipidome photooxidative stress transcriptome triacylglycerol. Xanthophylls mehr... |
Zusammenfassung: | © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology. Haematococcus pluvialis cells predominantly remain in the macrozooid stage under favourable environmental conditions but are rapidly differentiated into haematocysts upon exposure to various environmental stresses. Haematocysts are characterized by massive accumulations of astaxanthin sequestered in cytosolic oil globules. Lipidomic analyses revealed that synthesis of the storage lipid triacylglycerol (TAG) was substantially stimulated under high irradiance. Simultaneously, remodelling of membrane glycerolipids occurred as a result of dramatic reductions in chloroplast membrane glycolipids but remained unchanged or declined slightly in extraplastidic membrane glycerolipids. De novo assembly of transcriptomes revealed the genomic and metabolic features of this unsequenced microalga. Comparative transcriptomic analysis showed that so-called resting cells (haematocysts) may be more active than fast-growing vegetative cells (macrozooids) regarding metabolic pathways and functions. Comparative transcriptomic analyses of astaxanthin biosynthesis suggested that the non-mevalonate pathway mediated the synthesis of isopentenyl diphosphate, as the majority of genes involved in subsequent astaxanthin biosynthesis were substantially up-regulated under high irradiance, with the genes encoding phytoene synthase, phytoene desaturase, and β-carotene hydroxylase identified as the most prominent regulatory components. Accumulation of TAG under high irradiance was attributed to moderate up-regulation of de novo fatty acid biosynthesis at the gene level as well as to moderate elevation of the TAG assembly pathways. Additionally, inferred from transcriptomic differentiation, an increase in reactive oxygen species (ROS) scavenging activity, a decrease in ROS production, and the relaxation of over-reduction of the photosynthetic electron transport chain will work together to protect against photooxidative stress in H. pluvialis under high irradiance |
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Beschreibung: | Date Completed 01.04.2015 Date Revised 21.03.2024 published: Print-Electronic Citation Status MEDLINE |
ISSN: | 1460-2431 |
DOI: | 10.1093/jxb/eru206 |