Endoplasmic Reticulum Redox State Is Not Perturbed by Pharmacological or Pathological Endoplasmic Reticulum Stress in Live Pancreatic β-Cell...
We monitored ER redox together with transcriptional output of the Unfolded Protein Response (UPR) in INS-1 insulinoma cells stably expressing eroGFP (ER-redox-sensor) and mCherry protein driven by a GRP78 promoter (UPR-sensor). Live cell imaging, flow cytometry and biochemical characterization were...
Transcriptional response to deletion of the phosphatidylserine decarboxylase Psd1p in the yeast Saccharomyces cerevisiae.
We performed a DNA microarray analysis with a ∆psd1 deletion mutant. This approach revealed that 54 yeast genes were significantly up-regulated in the absence of PSD1 compared to wild type. Surprisingly, marked down-regulation of genes was not observed. A number of different cellular processes in di...
The phosphatidylethanolamine level of yeast mitochondria is affected by the mitochondrial components Oxa1p and Yme1p.
We report that deletion of OXA1 encoding an inner mitochondrial membrane protein translocase markedly affects the mitochondrial phosphatidylethanolamine level. In an oxa1Delta mutant, cellular and mitochondrial levels of phosphatidylethanolamine were lowered similar to a mutant with PSD1 deleted, an...
Action of protein disulfide isomerase on proinsulin exit from endoplasmic reticulum of pancreatic β-cells.
We have examined the effect of PDI knockdown (PDI-KD) in β-cells. The data establish that upon PDI-KD, oxidation of proinsulin to form native disulfide bonds is unimpaired and in fact enhanced. This is accompanied by improved proinsulin exit from the ER and increased total insulin secretion, with no...
Phosphatidylserine decarboxylases, key enzymes of lipid metabolism.
I PSDs include enzymes of eukaryotic mitochondria and bacterial origin which contain the amino acid sequence LGST as a characteristic motif. Type II PSDs are found in the endomembrane system of eukaryotes and contain a typical GGST motif. These characteristic motifs are considered as autocatalytic c...
A glucagon-like Peptide-1 analog reverses the molecular pathology and cardiac dysfunction of a mouse model of obesity.
We examine the cardiac effects of the glucagon-like peptide-1 analog liraglutide in a model of obesity, independent of changes in body weight. C57Bl6 mice were placed on a 45% high-fat diet (HFD) or a regular chow diet. Mice on HFD developed 46±2% and 60±2% greater body weight relative to regular ch...
A yeast mutant deleted ofGPH1bears defects in phospholipid metabolism
Chemistry and Physics of Lipids 164:S45 (2011)
SDF2L1 interacts with the ER-associated degradation machinery and retards the degradation of mutant proinsulin in pancreatic β-cells.
We show that SDF2L1 protein levels are increased in response to ER stress-inducing compounds, but not other cell stressors that we tested in insulinoma cell lines. SDF2L1 protein levels were also induced by expression of misfolded proinsulin in insulinoma cells and in islets from diabetic mice. Immu...
Phosphatidylethanolamine synthesized by four different pathways is supplied to the plasma membrane of the yeast Saccharomyces cerevisiae.
We examined the contribution of the four different pathways of phosphatidylethanolamine (PE) synthesis in the yeast Saccharomyces cerevisiae to the supply of this phospholipid to the plasma membrane. These pathways of PE formation are decarboxylation of phosphatidylserine (PS) by (i) phosphatidylser...
Phosphatidylethanolamine synthesized by three different pathways is supplied to the plasma membrane of the yeast Saccharomyces cerevisiae
Chemistry and Physics of Lipids 149:S53 (2007)