Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Yeast spore germination: time course

ABSTRACT: The process of Saccharomyces cerevisiae spore germination includes breakage of dormancy, morphological changes and resumption of vegetative growth. We have determined the global transcriptional response during the first two hours of spore germination in response to rich growth medium and glucose alone, and identified possible transcription factors regulating the different transcriptional programs. Saccharomyces cerevisiae Y55 spores subjected to YPD and glucose 2%. Samples are taken in triplicates (except for glucose 0 min were duplicates were taken) in time course series after glucose and nutrient addition. Total of 18 samples. RNA from dormant spores was used as reference RNA for all microarrays.

ORGANISM(S): Saccharomyces cerevisiae

SUBMITTER: Abraham Ericsson

PROVIDER: E-GEOD-29960 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

Time course gene expression profiling of yeast spore germination reveals a network of transcription factors orchestrating the global response.

Geijer Cecilia C Pirkov Ivan I Vongsangnak Wanwipa W Ericsson Abraham A Nielsen Jens J Krantz Marcus M Hohmann Stefan S

BMC genomics 20121015

<h4>Background</h4>Spore germination of the yeast Saccharomyces cerevisiae is a multi-step developmental path on which dormant spores re-enter the mitotic cell cycle and resume vegetative growth. Upon addition of a fermentable carbon source and nutrients, the outer layers of the protective spore wall are locally degraded, the tightly packed spore gains volume and an elongated shape, and eventually the germinating spore re-enters the cell cycle. The regulatory pathways driving this process are st ...[more]

PMID: 23066959

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Project description:Spermatophyte pollen tubes and root hairs have been used as single-cell-type model systems toward understanding the molecular processes underlying polar growth of plant cells. Horsetail (Equisetum arvense L.) is a perennial herb species in Equisetopsida, which creates separately growing spring and summer stems in its life cycle. The mature chlorophyllous spores produced from spring stems can germinate without dormancy. Here we report the cellular features and protein expression patterns in five stages of horsetail spore germination (mature spores, rehydrated spores, double-celled spores, germinated spores, and spores with protonemal cells). Using 2-DE combined with mass spectrometry, 80 proteins were found to be differentially expressed upon spore germination. Among them, proteins involved in photosynthesis, protein turnover, and energy supply were over-represented. Thirteen proteins appeared as isoforms on the gels, indicating the potential importance of post-translational modification. In addition, the dynamic changes of ascorbate peroxidase, peroxiredoxin, and dehydroascorbate reductase implied that reactive oxygen species homeostasis is critical in regulating cell division and tip-growth. The time course of germination and diverse expression patterns of proteins in photosynthesis, energy supply, lipid and amino acid metabolism indicated that heterotrophic and autotrophic metabolism were necessary in light-dependent germination of the spores. Twenty-six proteins were involved in protein synthesis, folding, and degradation, indicating that protein turnover is vital to spore germination and rhizoid tip-growth. Furthermore, the altered abundance of small G protein Ran1, 14-3-3 protein, actin, and Caffeoyl-CoA O-methyltransferase revealed that signaling transduction, vesicle trafficking, cytoskeleton dynamics, and cell wall modulation were critical to cell division and polar growth. These findings provide up-to-date evidences for understanding fern spore asymmetric division and rhizoid polar growth.

Project description:Description Bacillus subtilis forms highly resistant, metabolically inactive spores upon nutrient limitation. These endospores pose challenges to the food and medical sectors. Spores reactivate their metabolism upon contact with germinants through germination and outgrowth, and then develop into vegetative cells. However, the mechanism of the activation of the molecular machinery that triggers spore germination and outgrowth is unclear. To gain further insight into spore germination and outgrowth, the transcriptome and proteome changes during Bacillus subtilis spore conversion to vegetative cells were analyzed. The transcriptome analysis also allowed us to trace the different functional groups of genes expressed during this conversion. For each time-point sampled, the change in the spore proteome was quantitatively monitored relative to the reference proteome of 15N metabolically labelled vegetative cells. Of the quantified proteins, 60 percent are common to vegetative cells and spores, indicating that spores have a minimal set of proteins sufficient for the resumption of metabolism upon completion of germination. The shared proteins thus represent the most basic survival kit for spore-based life. Until the phase transition, defined as the completion of germination, we observed no significant change in the proteome or the transcriptome. Our analysis identified 34 abundant mRNA transcripts in the dormant spores, at least 31 of which were rapidly degraded after the phase transition. We observed 3152 differentially expressed genes, and demonstrated with our mass spectrometry analyses the differential expression of 323 proteins. Our data show that 173 proteins from dormant spores, both proteins unique to spores and proteins shared with vegetative cells, are lost after completion of germination. Further analysis is required to functionally interpret the observed protein loss. The observed diverse timing of the synthesis of different protein sets reveals a putative core-strategy of the revival of life starting from the B. subtilis spore.

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Dataset Information

Yeast spore germination: time course

Publications

Time course gene expression profiling of yeast spore germination reveals a network of transcription factors orchestrating the global response.

Similar Datasets

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