Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Changes in membrane lipid composition during Iron depletion and starvation in Chlamydomonas reinhardtii

ABSTRACT: C. reinhardtii cells exposed to abiotic stresses (e.g. iron-, nitrogen-, zinc- or phosphorus-deficiency) accumulate TAGs which are stored in lipid droplets. Here, we report that iron starvation leads to formation of lipids bodies and accumulation of TAGs. This occurs between 12 and 24 h of iron-starvation. C. reinhardtii cells deprived for iron have more saturated FA, due to the loss of functional FA desaturases, which are diiron enzymes. The abundance of a plastid ACP-acyl desaturase (FAB2) is significantly decreased to the same degree as observed for ferredoxin, which is a substrate of the desaturases. The increase in saturated FA (C16:0 and C18:0) is concomitant with the decrease in saturated FA (C16:4, C18:3 or C18:4). This pattern was observed for MGDG, DGTS or DGDG. When we monitored the absolute levels of glycerolipids, MGDG content dropped significantly after only 2 h of iron-starvation. On the other hand, DGTS and DGDG contents gradually decrease until a minimum is reached after 24-48 h of iron-deprivation. RNA-Seq analysis of iron-starved C. reinhardtii cells revealed significant changes in many transcripts coding for enzymes involved in FA metabolism. The mRNA abundances of genes coding for components involved in TAG accumulation (DGAT or MLDP) are increased. A more dramatic increase at the transcript level has been observed for many lipases, suggesting that a major remodeling of lipid membranes occurs during iron-starvation in C. reinhardtii. Sampling of Chlamydomonas CC-4532 (2137) cells cultivated photoheterotrophically (TAP) under iron-starvation condition (0 uM Fe-EDTA). Samples were collected from biological duplicates after washing in TAP medium lacking Fe at 0, 0.5, 1, 2, 4, 8, 12, 24 and 48 hours.

ORGANISM(S): Chlamydomonas reinhardtii

SUBMITTER: Sabeeha Merchant

PROVIDER: E-GEOD-44611 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

Remodeling of membrane lipids in iron-starved Chlamydomonas.

Urzica Eugen I EI Vieler Astrid A Hong-Hermesdorf Anne A Page M Dudley MD Casero David D Gallaher Sean D SD Kropat Janette J Pellegrini Matteo M Benning Christoph C Merchant Sabeeha S SS

The Journal of biological chemistry 20130827 42

Chlamydomonas reinhardtii cells exposed to abiotic stresses (e.g. nitrogen, zinc, or phosphorus deficiency) accumulate triacylglycerols (TAG), which are stored in lipid droplets. Here, we report that iron starvation leads to formation of lipid droplets and accumulation of TAGs. This occurs between 12 and 24 h after the switch to iron-starvation medium. C. reinhardtii cells deprived of iron have more saturated fatty acid (FA), possibly due to the loss of function of FA desaturases, which are iron ...[more]

PMID: 23983122

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Dataset Information

Changes in membrane lipid composition during Iron depletion and starvation in Chlamydomonas reinhardtii

Publications

Remodeling of membrane lipids in iron-starved Chlamydomonas.

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