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Transcriptome profile of Dictyostelium cell during ER-stress

ABSTRACT: The Unfolded Protein Response (UPR) is an adaptive pathway that restores cellular homeostasis after endoplasmic reticulum (ER) stress caused by an impairment of its protein folding capacity. The ER-resident kinase/ribonuclease Ire1 is the only UPR sensor that has been conserved during evolution from yeast to mammals; in these organisms, Ire1 transmits information from the ER to the nucleus trough the non-conventional splicing of Hac1 (yeast)/Xbp1 (metazoans) mRNA. We described the Dictyostelium discoideum ER-stress response and characterized its single bonafide Ire1 orthologue, IreA. We found that tunicamycin (TN) triggers a gene-expression program that increases the protein folding capacity of the ER and that alleviates ER protein load. Further, IreA resulted essential not only for cell-survival after TN-induced ER-stress, but also to accomplish about nearly 40% of the transcriptional changes induced upon a TN treatment. In addition, we described that autophagy is activated in Dictyostelium cells after a TN treatment and that autophagy-defective mutants exhibited increased sensitivity to this drug. The response of Dictyostelium cells to ER-stress involves the combined activation of an IreA-dependent gene expression program and the autophagy pathway.

ORGANISM(S): Dictyostelium discoideum

PROVIDER: GSE104409 | GEO | 2018/04/28

REPOSITORIES: GEO

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