Dataset Information

Putative stress sensors WscA and WscB are involved in hypo-osmotic and acidic pH stress tolerance in Aspergillus nidulans.

ABSTRACT: Wsc proteins have been identified in fungi and are believed to be stress sensors in the cell wall integrity (CWI) signaling pathway. In this study, we characterized the sensor orthologs WscA and WscB in Aspergillus nidulans. Using hemagglutinin-tagged WscA and WscB, we showed both Wsc proteins to be N- and O-glycosylated and localized in the cell wall and membrane, implying that they are potential cell surface sensors. The wscA disruptant (?wscA) strain was characterized by reduced colony and conidia formation and a high frequency of swollen hyphae under hypo-osmotic conditions. The deficient phenotype of the ?wscA strain was facilitated by acidification, but not by alkalization or antifungal agents. In contrast, osmotic stabilization restored the normal phenotype in the ?wscA strain. A similar inhibition was observed in the wscB disruptant strain, but to a lesser extent. In addition, a double wscA and wscB disruptant (?wscA ?wscB) strain was viable, but its growth was inhibited to a greater degree, indicating that the functions of the products of these genes are redundant. Transcription of ?-1,3-glucan synthase genes (agsA and agsB) was significantly altered in the wscA disruptant strain, resulting in an increase in the amount of alkali-soluble cell wall glucan compared to that in the wild-type (wt) strain. An increase in mitogen-activated protein kinase (MpkA) phosphorylation was observed as a result of wsc disruption. Moreover, the transient transcriptional upregulation of the agsB gene via MpkA signaling was observed in the ?wscA ?wscB strain to the same degree as in the wt strain. These results indicate that A. nidulans Wsc proteins have a different sensing spectrum and downstream signaling pathway than those in the yeast Saccharomyces cerevisiae and that they play an important role in CWI under hypo-osmotic and acidic pH conditions.

SUBMITTER: Futagami T

PROVIDER: S-EPMC3209062 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Putative stress sensors WscA and WscB are involved in hypo-osmotic and acidic pH stress tolerance in Aspergillus nidulans.

Futagami Taiki T Nakao Seiki S Kido Yayoi Y Oka Takuji T Kajiwara Yasuhiro Y Takashita Hideharu H Omori Toshiro T Furukawa Kensuke K Goto Masatoshi M

Eukaryotic cell 20110916 11

Wsc proteins have been identified in fungi and are believed to be stress sensors in the cell wall integrity (CWI) signaling pathway. In this study, we characterized the sensor orthologs WscA and WscB in Aspergillus nidulans. Using hemagglutinin-tagged WscA and WscB, we showed both Wsc proteins to be N- and O-glycosylated and localized in the cell wall and membrane, implying that they are potential cell surface sensors. The wscA disruptant (ΔwscA) strain was characterized by reduced colony and co ...[more]

PMID: 21926329

Similar Datasets

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.

Dataset Information

Putative stress sensors WscA and WscB are involved in hypo-osmotic and acidic pH stress tolerance in Aspergillus nidulans.

Publications

Putative stress sensors WscA and WscB are involved in hypo-osmotic and acidic pH stress tolerance in Aspergillus nidulans.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets