Coupling the MAPK Slt2/ERK1 Pathway and IRE1-driven UPR Through Transcription Factor Rlm1/MEF2.

ABSTRACT: Unfolded protein response (UPR) is a conserved cellular strategy that enhances the protein folding capacity of cells under stress conditions. In Saccharomyces cerevisiae, the dual kinase RNase IRE1 initiates the UPR by catalyzing the cytosolic splicing of HAC1 mRNA, a process conserved in humans where IRE1 splices XBP1 mRNA. The spliced HAC1/XBP1 mRNA yields a transcription factor that upregulates the expression of protein-folding enzymes and chaperones, thereby boosting the cell's ability to cope with unfolded proteins. Our study demonstrates that the UPR involves two distinct phases. The early phase operates predominantly through the canonical IRE1 signaling pathway, while the later phase involves additional regulation by the MAP kinase Slt2 or its human ortho

SUBMITTER: Chakraborty A 

PROVIDER: S-EPMC12776503 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature