IFIBYNE   05513
INSTITUTO DE FISIOLOGIA, BIOLOGIA MOLECULAR Y NEUROCIENCIAS
Unidad Ejecutora - UE
artículos
Título:
The Saccharomyces cerevisiae YFR041C/ERJ5 gene encoding a novel type I membrane protein with a J domain is required to preserve the folding capacity of the endoplasmic reticulum.
Autor/es:
FAMÁ, M.C.; RADEN, D.; ZACCHI, N.; LEMOS, D.R.; ROBINSON, A.S.; SILBERSTEIN, S.
Revista:
BBA Mol. Cell Research
Editorial:
Elsevier
Referencias:
Año: 2007 p. 232 - 242
Resumen:
YFR041C/ERJ5 was identified in Saccharomyces cerevisiae as a gene regulated by the unfolded protein response pathway (UPR). The openreading frame of the gene has a J domain characteristic of the DnaJ chaperone family of proteins that regulate the activity of Hsp70 chaperones.We determined the expression and topology of Erj5p, a type I membrane protein with a J domain in the lumen of the endoplasmic reticulum (ER)that colocalizes with Kar2p, the major Hsp70 in the yeast ER. We identified synthetic interactions of delta erj5 with mutations in genes involved inprotein folding in the ER (kar2-159, delta scj1delta jem1) and in the induction of the unfolded protein response (delta ire1). Loss of Erj5p in yeast cells withimpaired ER protein folding capacity increased sensitivity to agents that cause ER stress. We identified the ERJ5 mRNA and confirmed thatagents that promote accumulation of misfolded proteins in the ER regulate its abundance. We found that loss of the non-essential ERJ5 gene leadsto a constitutively induced UPR, indicating that ERJ5 is required for maintenance of an optimal folding environment in the yeast ER.