Showing papers by "Fumihiko Urano published in 2004"

Compartment-specific perturbation of protein handling activates genes encoding mitochondrial chaperones

Abstract: Protein folding in the mitochondria is assisted by nuclear-encoded compartment-specific chaperones but regulation of the expression of their encoding genes is poorly understood. We found that the mitochondrial matrix HSP70 and HSP60 chaperones, encoded by the Caenorhabditis elegans hsp-6 and hsp-60 genes, were selectively activated by perturbations that impair assembly of multi-subunit mitochondrial complexes or by RNAi of genes encoding mitochondrial chaperones or proteases, which lead to defective protein folding and processing in the organelle. hsp-6 and hsp-60 induction was specific to perturbed mitochondrial protein handling, as neither heat-shock nor endoplasmic reticulum stress nor manipulations that impair mitochondrial steps in intermediary metabolism or ATP synthesis activated the mitochondrial chaperone genes. These observations support the existence of a mitochondrial unfolded protein response that couples mitochondrial chaperone gene expression to changes in the protein handling environment in the organelle.

Methods For Diagnosing And Treating Endoplasmic Reticulum (er) Stress Diseases

Abstract: The present invention provides methods and reagents to quantify endoplasmic reticulum stress (ER stress) levels, and methods and compounds for treating ER stress disorders such as diabetes. Methods for quantifying ER stress in mammalian cells are exemplified.