Steroids, essential for mammalian survival, are initiated by cholesterol transport by steroidogenic acute regulatory protein (StAR). Appropriate protein folding is an essential requirement of activity. Endoplasmic reticulum (ER) chaperones assist in folding of cytoplasmic proteins, whereas mitochondrial chaperones fold only mitochondrial proteins. We show that glucose regulatory protein 78 (GRP...

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by abnormal proliferation of synoviocytes, leukocyte infiltration, and angiogenesis. The endoplasmic reticulum (ER) is the site of biosynthesis for all secreted and membrane proteins. The accumulation of unfolded proteins in the ER leads to a condition known as ER stress. Failure of the ER's adaptive capacity results in a...

NPGPx is a member of the glutathione peroxidase (GPx) family; however, it lacks GPx enzymatic activity due to the absence of a critical selenocysteine residue, rendering its function an enigma. Here, we show that NPGPx is a newly identified stress sensor that transmits oxidative stress signals by forming the disulfide bond between its Cys57 and Cys86 residues. This oxidized form of NPGPx binds ...

Abstract Diffuse intrinsic pontine gliomas (DIPGs) are highly lethal pediatric brain tumors. Thus, there is an urgent need for novel therapeutics. While chimeric antigen receptor (CAR) T-cell therapy has the potential to meet this and early phase clinical studies with CAR T cells have shown safety some efficacy, additional needed understand lack of efficacy against DIPGs. The goal study was ide...

Human BiP/GRP78 is involved in the folding and assembly of proteins in the endoplasmic reticulum. The proteins for crystallization in good amount and quality are prerequisites for obtaining ideal crystals. To meet these requirements, different BiP/GRP78 constructs, competent cells, vectors, and concentrations of inducer were tested in order to obtain soluble BiP/GRP78 protein with the highest a...

To reveal the effects of cadmium exposure on the endoplasmic reticulum (ER) stress response, we examined the expression and function of 78-kDa glucose-regulated protein (Grp78) , an ER-resident molecular chaperone, in LLC-PK1 cells. In cells treated with 10 microM cadmium chloride, Grp78 protein levels increased after 6 hr and remained elevated at 24 hr. When cells were incubated with 1-20 micr...

Treatment of several types of cancer such as lung, breast, prostate, and pancreas has shown notable progresses in the past decades. However, after an initial response, tumors eventually became resistant to chemotherapy. This phenomenon, known as chemoresistance, accounts for the death of most cancer patients. Several studies in patients refractory to therapy have revealed the upregulation of th...

Little is known about the extracellular signaling factors that govern mammary stem cell behavior. Here, we identify CRIPTO and its cell-surface receptor GRP78 as regulators of stem cell behavior in isolated fetal and adult mammary epithelial cells. We develop a CRIPTO antagonist that promotes differentiation and reduces self-renewal of mammary stem cell-enriched populations cultured ex vivo. By...

The potential pro-survival role of phosphatidylinositol 3-kinase (PI3K)/Akt during endoplasmic reticulum stress has been well-characterized. However, the detailed mechanisms remain largely unknown. Here, we showed that PI3K/Akt inhibition promoted endoplasmic reticulum stress-induced apoptosis in a glucose-regulated protein 78 (GRP78)-dependent manner. During endoplasmic reticulum stress, high ...

PURPOSE Procollagen I is synthesized and intracellularly degraded in corneal endothelial cells (CEC), whereas type IV and VIII collagens are secreted into Descemet's membrane. In our previous study, we demonstrated that procollagen I synthesized by CEC is improperly folded and that the molecule was largely colocalized with protein disulfide isomerase (PDI) within the endoplasmic reticulum (ER)....