Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Identification of the calcium-responsive genes dependent on CrzA in the filamentous fungus Aspergillus nidulans

ABSTRACT: Microarray analysis was used to identify the calcium-responsive genes dependent on CrzA in the filamentous fungus Aspergillus nidulans. In order to identify such genes, we conducted the two types of experiment. One was a comparison between wild type with calcium treatment and wild type without calcium treatment. Another was a comparison between wild type with calcium treatment and crzA mutant with calcium treatment. From a comparison between the results of these experiments, we could identify the genes whose expression was induced or repressed in response to calcium in a manner dependent on CrzA. KEY WORD; Aspergillus nidulans, calcium response, crzA Conidia of wild type or crzA mutant strains were incubated at 37C in CD medium for 18h and treated with or without calcium (final concentration; 50 mM) for 15 min. The mycelia were harvested and frozen in liquid nitrogen, ground to a powder, and used for RNA preparation. mRNA was purified and used for hybridization experiments. A total of 2 hybridizations were performed for each microarray experiment described in the summary. The following replicates were carried out: 1. In-slide replicates were carried out for each analyses. 2. Dye swap replicates were carried out for each analyses. The slides were scanned with an Axon GenePix 4000B scanner (Molecular Devices). The resulting TIFF images were imported into GenePix Pro and fluorescent intensity of spots were calculated for each of the Cy3 and Cy5 channels. Global normalization was applied to all analyses. Following normalization, spots whose Cy3 or Cy5 intensity was less than 0 were removed from the data set (the exceptional case was that intensity of the other channel was more than 100). The dye-swap replicates and in-slide replicates were subjected to all analyses. Finally, gene expression ratios (channel 2/channel 1) were calculated for each replicates. Gene expression was considered to be significantly higher or lower whenever the spot intensity changed by at least 2-fold in all four replicates.

ORGANISM(S): Emericella nidulans

SUBMITTER: Daisuke Hagiwara

PROVIDER: E-GEOD-12953 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

Functional analysis of C2H2 zinc finger transcription factor CrzA involved in calcium signaling in Aspergillus nidulans.

Hagiwara Daisuke D Kondo Atsushi A Fujioka Tomonori T Abe Keietsu K

Current genetics 20081111 6

Calcium signaling systems are widely employed in eukaryotes and are implicated in the regulation of diverse biological processes. Calcineurin is an important signaling component, which mediates ion homeostasis and virulence in several fungi. Based on intensive studies conducted on budding yeast, transcription factor Crz1p is thought to be a target of calcineurin. To provide insight into calcium signaling, a Crz1p homolog (CrzA) in a filamentous fungus Aspergillus nidulans was identified and its ...[more]

PMID: 19002465

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Project description:Microarray analysis was used to identify the fludioxonil-responsive genes dependent on SskA, SrrA, HogA, and AtfA in the filamentous fungus Aspergillus nidulans. In order to identify such genes, we conducted the several types of experiment. One was a comparison between wild type treated with fludioxonil and without the treatment (Exp.1). Others were comparison between wild type treated with fludioxonil and each mutant (sskA, Exp.2; srrA, Exp.3; hogA, Exp.4; atfA, Exp.5) treated with fludioxonil. Compared the result of Exp.1 with that of other experiments, we could identify the genes whose expression was induced or repressed in response to fludioxonil in a manner dependent on SskA, SrrA, HogA, or AtfA. KEY WORD; Aspergillus nidulans, fludioxonil, SskA, SrrA, HogA, AtfA Conidia of wild type or each mutant were cultured at 37C in 100ml CD medium containing 2% glucose for 18h and treated with fludioxonil (final concentration; 10 ug/ml) or DMSO (as a solvent control) for 15 min. The mycelia were harvested and frozen in liquid nitrogen, ground to powder, and used for RNA preparation. mRNA was purified and used for hybridization experiments. A total of 2 hybridizations were performed for each microarray experiment described in the summary. The following replicates were carried out: 1. In-slide replicates were carried out for each analysis. 2. Dye swap replicates were carried out for each experiment. The slides were scanned with an Axon GenePix 4000B scanner (Molecular Devices). The resulting TIFF images were imported into GenePix Pro and fluorescent intensity of spots were calculated for each of the Cy3 and Cy5 channels. Global normalization was applied to all analyses. Following normalization, spots whose Cy3 or Cy5 intensity was less than 0 were removed from the data set (the exceptional case was that intensity of the other channel was more than 100). The dye-swap replicates and in-slide replicates were subjected to all analyses. Finally, gene expression ratios (test/reference) were calculated for each replicates. Gene expression was considered to be significantly higher or lower whenever the spot intensity changed by at least 3-fold in all four replicates for each experiment.

Project description:Microarray analysis was used to identify the osmotic stress-responsive genes dependent on HogA and AtfA in the filamentous fungus Aspergillus nidulans. In order to identify such genes, we conducted the several types of experiment. One was a comparison between wild type with and without osmotic shock (Exp.6). Others were comparison between wild type with osmotic shock and each mutant (hogA, Exp.7; atfA, Exp.8) with osmotic shock. Compared the result of Exp.6 with other experiments, we could identify the genes whose expression was induced or repressed in response to osmotic stress in a manner dependent on HogA and AtfA. KEY WORD; Aspergillus nidulans, osmotic stress, HogA, AtfA Conidia of wild type or each mutant were cultured at 37C in 100ml CD medium containing 2% glucose for 18h, and 50 ml of 3 M sorbitol was added (final concentration; 1 M) or equivalent volume of water (as a control) for 15 min. The mycelia were harvested and frozen in liquid nitrogen, ground to powder, and used for RNA preparation. mRNA was purified and used for hybridization experiments. A total of 2 hybridizations were performed for each microarray experiment described in the summary. The following replicates were carried out: 1. In-slide replicates were carried out for each analysis. 2. Dye swap replicates were carried out for each experiment. The slides were scanned with an Axon GenePix 4000B scanner (Molecular Devices). The resulting TIFF images were imported into GenePix Pro and fluorescent intensity of spots were calculated for each of the Cy3 and Cy5 channels. Global normalization was applied to all analyses. Following normalization, spots whose Cy3 or Cy5 intensity was less than 0 were removed from the data set (the exceptional case was that intensity of the other channel was more than 100). The dye-swap replicates and in-slide replicates were subjected to all analyses. Finally, gene expression ratios (channel 2/channel 1) were calculated for each replicates. Gene expression was considered to be significantly higher or lower whenever the spot intensity changed by at least 2-fold in all four replicates for each experiment.

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Dataset Information

Identification of the calcium-responsive genes dependent on CrzA in the filamentous fungus Aspergillus nidulans

Publications

Functional analysis of C2H2 zinc finger transcription factor CrzA involved in calcium signaling in Aspergillus nidulans.

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