The zoospores of the thraustochytrid Aurantiochytrium limacinum: Transcriptional reprogramming and lipid metabolism associated to their specific functions

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representing cells containing about twice as much DNA as the cells forming the first peak (Fig. 1C).  Table 2). In addition, many transcripts encoding 179 the signaling transduction route were up-regulated, e.g. 14 Ras GTPases as well as several proteins 180 linked to the cAMP signaling pathway (present in the G protein item in Fig. 2A; Supplementary Table   181 2).  Genes involved in nitrogen and amino acid metabolisms were highly differentially expressed (Fig. 2D).

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About 20 genes involved in nitrate and ammonium transport and nitrogen assimilation (such as

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Furthermore, in oomycetes a very peculiar GPCR system evolved (Meijer and Govers, 2006  appear eight hours after transfer in P medium (Fig. 4E). Assuming that zoosporogenesis is induced 396 soon after the transfer, zoospore formation and release appear slower in thraustochytrids than in 397 oomycetes, suggesting that different processes could be involved.  Table 5).

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For the gene differential expression experiment along a six day-growth, a six-day-old culture grown 495 on R was inoculated in 50 mL of either R or P fresh culture media at an initial cell concentration of 496 5×10 5 cells·mL -1 . 1.5 mL were gathered by centrifugation at the following time points day 1 (D1), day 497 2 (D2), day 4 (D4), and day 6 (D6). RNA was extracted and reverse transcribed as described above. To reduce variability, a six-day old R-grown culture was inoculated at 5×10 5 cells·mL -1 in 50 mL of P 506 medium to induce zoospore formation. After 24 hours, 200 µL of the culture were spread onto a 1 % 507 agar-R plate. One of the single colonies was picked and cultivated in R medium for six days. Cells 508 were inoculated in triplicate into 50 mL of either fresh R or fresh P media at a concentration of 5×10 5 509 cells·mL -1 . R and P cultures were harvested at time points 15 hours and 24 hours, corresponding to 510 the production peaks of mononucleated non-motile cells and zoospores, respectively (Dellero et al.,

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Electrode was first calibrated using media saturated with either air or argon for the 100 % and the 0 520 %, respectively. Oxygen consumption was directly monitored in 1 mL of culture medium.           were chosen as representatives of FA synthesis. Acad1 (acyl-CoA dehydrogenase, β-oxidation in mitochondria) and Acox1 (acyl-CoA oxidase, β-oxidation in peroxisomes) were chosen for FA degradation.