Please note that we have stopped the regular imports of Gene Expression Omnibus (GEO) data into ArrayExpress. This may not be the latest version of this experiment.
E-GEOD-24366 - Global Changes following N-deprivation in Chlamydomonas: 454 sequencing
Released on 24 September 2010, last updated on 23 December 2017
Chlamydomonas reinhardtii forms lipid droplets rich in triacylglycerols when nutrient-deprived. To begin studying the mechanisms underlying this process, N-deprivation was used to induce triacylglycerol accumulation and changes in developmental programs such as gametogenesis. Comparative global analysis of transcripts under induced and non-induced conditions was applied as a first approach to study molecular changes that promote or accompany triacylglycerol accumulation in cells encountering a new nutrient environment. Towards this goal, high-throughput sequencing technology was employed to generate large numbers of expressed sequence tags of 8 biologically independent libraries (2 454 libraries, 6 Illumina libraries), four for each condition, N-replete and N-deprived, that allowed a statistically sound comparison of expression levels under the two tested conditions. Inferences on metabolism based on transcriptional analysis can only be indirect but were supported in parts by biochemical experiments. N-deprivation led to a marked redirection of metabolism as the carbon source acetate was no longer converted to cell building blocks by the glyoxylate cycle and gluconeogensis, but funneled directly into fatty acid biosynthesis. Protein biosynthesis and photosynthesis were down-regulated and genes of gametogenesis activated. A notable finding was that the genes encoding photosynthetic accessory PSBS proteins of currently unclear function in C. reinhardtii were strongly expressed following N-deprivation, providing a clue to their physiological role. Lipase-encoding genes were found to be some of the most regulated following N-deprivation, suggesting a remodeling of membranes under these conditions. The data provided here represent a rich source for the exploration of the mechanism of oil accumulation in microalgae. Examing N-replete and N-deprived conditions. One biological replicate each condition.
RNA-seq of coding RNA
Guangxi Wu <email@example.com>, Christoph Benning
Changes in transcript abundance in Chlamydomonas reinhardtii following nitrogen deprivation predict diversion of metabolism. Miller R, Wu G, Deshpande RR, Vieler A, Gartner K, Li X, Moellering ER, Zauner S, Cornish AJ, Liu B, Bullard B, Sears BB, Kuo MH, Hegg EL, Shachar-Hill Y, Shiu SH, Benning C. , PMID:20935180