Dataset Information

The response of Chlamydomonas reinhardtii to nitrogen deprivation: a systems biology analysis

ABSTRACT:

Drastic alteration in macronutrients causes large changes in gene expression in the photosynthetic unicellular alga Chlamydomonas reinhardtii. Preliminary data suggested that cells follow a biphasic response to this change hinging on the initiation of lipid accumulation, and we hypothesized that drastic repatterning of metabolism also followed this biphasic modality. To test this hypothesis, transcriptomic, proteomic, and metabolite changes that occur under nitrogen (N) deprivation were analyzed. Eight sampling times were selected covering the progressive slowing of growth and induction of oil synthesis between 4 and 6 h after N deprivation. Results of the combined, systems-level investigation indicated that C. reinhardtii cells sense and respond on a large scale within 30 min to a switch to N-deprived conditions turning on a largely gluconeogenic metabolic state, which then transitions to a glycolytic stage between 4 and 6 h after N depletion. This nitrogen-sensing system is transduced to carbon- and nitrogen-responsive pathways, leading to down-regulation of carbon assimilation and chlorophyll biosynthesis, and an increase in nitrogen metabolism and lipid biosynthesis. For example, the expression of nearly all the enzymes for assimilating nitrogen from ammonium, nitrate, nitrite, urea, formamide/acetamide, purines, pyrimidines, polyamines, amino acids and proteins increased significantly. Although arginine biosynthesis enzymes were also rapidly up-regulated, arginine pool size changes and isotopic labeling results indicated no increased flux through this pathway.

Data availability:

The proteomics data have been deposited into the ProteomeXchange Consortium via the PRIDE partner repository with the data set identifier PXD002377.

OTHER RELATED OMICS DATASETS IN: PXD002377

INSTRUMENT(S): Pagasus 4D GC-MS (LECO)

SUBMITTER: Jeong-Jin Park

PROVIDER: MTBLS208 | MetaboLights | 2015-06-29

REPOSITORIES: MetaboLights

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Dataset's files

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			Action	DRS
	MTBLS208	Other
	FILES	Other
	a_MTBLS208_chlamydomonas_primary_metabolites_under_nitrogen_deprivation_metabolite_profiling_mass_spectrometry.txt	Txt
	i_Investigation.txt	Txt
	m_MTBLS208_chlamydomonas_primary_metabolites_under_nitrogen_deprivation_metabolite_profiling_mass_spectrometry_v2_maf.tsv	Tabular

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Publications

The response of Chlamydomonas reinhardtii to nitrogen deprivation: a systems biology analysis.

Park Jeong-Jin JJ Wang Hongxia H Gargouri Mahmoud M Deshpande Rahul R RR Skepper Jeremy N JN Holguin F Omar FO Juergens Matthew T MT Shachar-Hill Yair Y Hicks Leslie M LM Gang David R DR

The Plant journal : for cell and molecular biology 20150201 4

PMID: 25515814

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