Dual regulation of SLC25A39 by AFG3L2 and iron controls mitochondrial glutathione homeostasis.

Organelle transporters define metabolic compartmentalization, and how this metabolite transport process can be modulated is poorly explored. Here, we discovered that human SLC25A39, a mitochondrial transporter critical for mitochondrial glutathione uptake, is a short-lived protein under dual regulation at the protein level. Co-immunoprecipitation mass spectrometry and CRISPR knockout (KO) in mammalian cells identified that mitochondrial m-AAA protease AFG3L2 is responsible for degrading SLC25A39 through the matrix loop 1.

Loss of cis-PTase function in the liver promotes a highly penetrant form of fatty liver disease that rapidly transitions to hepatocellular carcinoma.

Obesity-linked fatty liver is a significant risk factor for hepatocellular carcinoma (HCC); however, the molecular mechanisms underlying the transition from non-alcoholic fatty liver disease (NAFLD) to HCC remains unclear. The present study explores the role of the endoplasmic reticulum (ER)-associated protein NgBR, an essential component of the cis-prenyltransferases (cis-PTase) enzyme, in chronic liver disease. Here we show that genetic depletion of NgBR in hepatocytes of mice (N-LKO) intensifies triacylglycerol (TAG) accumulation, inflammatory responses, ER/oxidative stress, and liver fibrosis, ultimately resulting in HCC development with 100% penetrance after four months on a high-fat diet.

TNFα increases the degradation of pyruvate dehydrogenase kinase 4 by the Lon protease to support proinflammatory genes.

The endothelium is a major target of the proinflammatory cytokine, tumor necrosis factor alpha (TNFα). Exposure of endothelial cells (EC) to proinflammatory stimuli leads to an increase in mitochondrial metabolism; however, the function and regulation of elevated mitochondrial metabolism in EC in response to proinflammatory cytokines remain unclear. Studies using high-resolution metabolomics and C-glucose and C-glutamine labeling flux techniques showed that pyruvate dehydrogenase activity (PDH) and oxidative tricarboxylic acid cycle (TCA) flux are elevated in human umbilical vein ECs in response to overnight (16 h) treatment with TNFα (10 ng/mL).

Progressive myoclonus epilepsies-Residual unsolved cases have marked genetic heterogeneity including dolichol-dependent protein glycosylation pathway genes.

Progressive myoclonus epilepsies (PMEs) comprise a group of clinically and genetically heterogeneous rare diseases. Over 70% of PME cases can now be molecularly solved. Known PME genes encode a variety of proteins, many involved in lysosomal and endosomal function.

Structural elucidation of the -prenyltransferase NgBR/DHDDS complex reveals insights in regulation of protein glycosylation.

prenyltransferase (PTase) catalyzes the rate-limiting step in the synthesis of glycosyl carrier lipids required for protein glycosylation in the lumen of endoplasmic reticulum. Here, we report the crystal structure of the human NgBR/DHDDS complex, which represents an atomic resolution structure for any heterodimeric -PTase. The crystal structure sheds light on how NgBR stabilizes DHDDS through dimerization, participates in the enzyme's active site through its C-terminal -RXG- motif, and how phospholipids markedly stimulate -PTase activity.

Endothelial cell-glucocorticoid receptor interactions and regulation of Wnt signaling.

Vascular inflammation is present in many cardiovascular diseases, and exogenous glucocorticoids have traditionally been used as a therapy to suppress inflammation. However, recent data have shown that endogenous glucocorticoids, acting through the endothelial glucocorticoid receptor, act as negative regulators of inflammation. Here, we performed ChIP for the glucocorticoid receptor, followed by next-generation sequencing in mouse endothelial cells to investigate how the endothelial glucocorticoid receptor regulates vascular inflammation.

Long-Chain Polyprenols Promote Spore Wall Formation in .

Dolichols are isoprenoid lipids of varying length that act as sugar carriers in glycosylation reactions in the endoplasmic reticulum. In , there are two -prenyltransferases that synthesize polyprenol-an essential precursor to dolichol. These enzymes are heterodimers composed of Nus1 and either Rer2 or Srt1.

A conserved C-terminal RG motif in the NgBR subunit of -prenyltransferase is critical for prenyltransferase activity.

-Prenyltransferases (-PTs) constitute a large family of enzymes conserved during evolution and present in all domains of life. In eukaryotes and archaea, -PT is the first enzyme committed to the synthesis of dolichyl phosphate, an obligate lipid carrier in protein glycosylation reactions. The homodimeric bacterial enzyme, undecaprenyl diphosphate synthase, generates 11 isoprene units and has been structurally and mechanistically characterized in great detail.

Ultrahypofractionated CyberKnifeTM based stereotactic radiotherapy versus conventional radiotherapy in patients with prostate cancer - acute toxicity evaluation in two phase II prospective studies.

Our purpose was to compare the acute toxicity of ultrahypofractionated CyberKnifeTM based stereotactic radiotherapy (SBRT Arm) and conventional radiotherapy (EBRT Arm) in prostate cancer patients. Two-hundred-sixteen men with prostate cancer were enrolled in our prospective studies. One-hundred and nine were irradiated using CyberKnife to total dose of 36,25 Gy in 5 fractions.

cis-Prenyltransferase: New Insights into Protein Glycosylation, Rubber Synthesis, and Human Diseases.

cis-Prenyltransferases (cis-PTs) constitute a large family of enzymes conserved during evolution and present in all domains of life. cis-PTs catalyze consecutive condensation reactions of allylic diphosphate acceptor with isopentenyl diphosphate (IPP) in the cis (Z) configuration to generate linear polyprenyl diphosphate. The chain lengths of isoprenoid carbon skeletons vary widely from neryl pyrophosphate (C10) to natural rubber (C>10,000).

NgBR is essential for endothelial cell glycosylation and vascular development.

NgBR is a transmembrane protein identified as a Nogo-B-interacting protein and recently has been shown to be a subunit required for cis-prenyltransferase (cisPTase) activity. To investigate the integrated role of NgBR in vascular development, we have characterized endothelial-specific NgBR knockout embryos. Here, we show that endothelial-specific NgBR knockout results in embryonic lethality due to vascular development defects in yolk sac and embryo proper.

CyberKnife-based prostate cancer patient radioablation - early results of irradiation in 200 patients.

Introduction: Prostrate cancer (PC) is one of the most common malignancies and is frequently treated with an 8-week course of radiotherapy. CyberKnife (CK) based radioablation enables completion of therapy within 5-9 days. The aim of this study is an evaluation of the effectiveness and tolerance of CyberKnife-based radioablation in prostate cancer patients.

Acute toxicity of robotic ultrahypofractionated radiotherapy CyberKnifeTM in prostate cancer patients.

Our purpose was to evaluate the toxicity of CyberKnifeTM based fractionated stereotactic radiotherapy (FSRT) in prostate cancer patients. One-hunred-thirty-two men with low (62) and intermediate (70) prostate cancer were enrolled in our prospective study. Mean age was 69.

Prognostic value and clinical correlations of 18-fluorodeoxyglucose metabolism quantifiers in gastric cancer.

Aim: To investigate the correlations of pre-treatment positron emission tomography-computer tomography (PET-CT) metabolic quantifiers with clinical data of unstratified gastric cancer (GC) patients.

Methods: Forty PET-CT scans utilising 18-fluorodeoxyglucose in patients who received no prior treatment were analysed. Analysis involved measurements of maximum and mean standardised uptake volumes (SUV), coefficient of variation (COV), metabolic tumour volumes and total lesion glycolysis of different thresholds above which the tumor volumes were identified.

Influence of interfraction motion on margins for radiotherapy of gastric cancer.

Objective: The aim of this study was to evaluate interfraction uncertainties using kilovoltage (kV) radiographs for patients with gastric cancer during chemoradiotherapy and to calculate the planning target volume (PTV) margins.

Methods: 1284 measurements of set-up errors were analysed for treated patients. The measurements of craniocaudal (axis y), laterolateral (axis x) and anteroposterior (axis z) shifts in kV radiographs were performed.

Radiotherapy and chemoradiotherapy as a novel option for the treatment of locally advanced inoperable gastric adenocarcinoma: A phase II study.

This phase II trial aimed to evaluate the tolerance and efficacy of radical radiotherapy or chemoradiotherapy in patients with primarily inoperable gastric cancer. The analysis was based on 13 patients with primarily inoperable gastric cancer. A total of 6 (46.

Mutation of Nogo-B receptor, a subunit of cis-prenyltransferase, causes a congenital disorder of glycosylation.

Dolichol is an obligate carrier of glycans for N-linked protein glycosylation, O-mannosylation, and GPI anchor biosynthesis. cis-prenyltransferase (cis-PTase) is the first enzyme committed to the synthesis of dolichol. However, the proteins responsible for mammalian cis-PTase activity have not been delineated.

[Peritoneal dialysis as an alternative in the treatment of patient with heart failure refractory to conventional therapy].

Peritoneal ultrafiltration and dialysis is a feasible therapy in selected patients with heart failure (HF). This method is effective in slow and continuous plasma volume reduction, maintenance of normonatraemia, the removal of cytokines and humoral factors involved in the development and progression of HF and middle-molecule clearance. We present a 26-year-old woman with HF refractory to conventional treatment.

Molecular characterization of the cis-prenyltransferase of Giardia lamblia.

Giardia lamblia, the protist that causes diarrhea, makes an Asn-linked-glycan (N-glycan) precursor that contains just two sugars (GlcNAc(2)) attached by a pyrophosphate linkage to a polyprenol lipid. Because the candidate cis-prenyltransferase of Giardia appears to be more similar to bacterial enzymes than to those of most eukaryotes and because Giardia is missing a candidate dolichol kinase (ortholog to Saccharomyces cerevisiae SEC59 gene product), we wondered how Giardia synthesizes dolichol phosphate (Dol-P), which is used to make N-glycans and glycosylphosphatidylinositol (GPI) anchors. Here we show that cultured Giardia makes an unsaturated polyprenyl pyrophosphate (dehydrodolichol), which contains 11 and 12 isoprene units and is reduced to dolichol.

The YTA7 gene is involved in the regulation of the isoprenoid pathway in the yeast Saccharomyces cerevisiae.

The isoprenoid pathway in yeasts is important not only for sterol biosynthesis but also for the production of nonsterol molecules, deriving from farnesyl diphosphate (FPP), implicated in N-glycosylation and biosynthesis of heme and ubiquinones. FPP formed from mevalonate in a reaction catalyzed by FPP synthase (Erg20p). In order to investigate the regulation of Erg20p in Saccharomyces cerevisiae, we searched for its protein partners using a two-hybrid screen, and identified five interacting proteins, among them Yta7p.

Dolichyl-phosphate-glucose is used to make O-glycans on glycoproteins of Trichomonas vaginalis.

Trichomonas vaginalis, the protist that causes vaginal itching, has a huge genome with numerous gene duplications. Recently we found that Trichomonas has numerous genes encoding putative dolichyl-phosphate-glucose (Dol-P-Glc) synthases (encoded by ALG5 genes) despite the fact that Trichomonas lacks the glycosyltransferases (encoded by ALG6, ALG8, and ALG10 genes) that use Dol-P-Glc to glucosylate dolichyl-PP-linked glycans. In addition, Trichomonas does not have a canonical DPM1 gene, encoding a dolichyl-P-mannose (Dol-P-Man) synthase.

Prenylation of Saccharomyces cerevisiae Chs4p Affects Chitin Synthase III activity and chitin chain length.

Chs4p (Cal2/Csd4/Skt5) was identified as a protein factor physically interacting with Chs3p, the catalytic subunit of chitin synthase III (CSIII), and is indispensable for its enzymatic activity in vivo. Chs4p contains a putative farnesyl attachment site at the C-terminal end (CVIM motif) conserved in Chs4p of Saccharomyces cerevisiae and other fungi. Several previous reports questioned the role of Chs4p prenylation in chitin biosynthesis.

Functional relationships between the Saccharomyces cerevisiae cis-prenyltransferases required for dolichol biosynthesis.

In the yeast Saccharomyces cerevisiae the RER2 and SRT1 genes encode Rer2 and Srt1 proteins with cis-prenyltransferase (cis-PT-ase) activity. Both cis-PT-ases utilize farnesyl diphosphate (FPP) as a starter for polyprenyl diphosphate (dolichol backbone) formation. The products of the Rer2 and Srt1 proteins consist of 14-17 and 18-23 isoprene units, respectively.

Rsp5 ubiquitin ligase affects isoprenoid pathway and cell wall organization in S. cerevisiae.

Dimethylallyl diphosphate, an isomer of isopentenyl diphosphate, is a common substrate of Mod5p, a tRNA modifying enzyme, and the farnesyl diphosphate synthase Erg20p, the key enzyme of the isoprenoid pathway. rsp5 mutants, defective in the Rsp5 ubiquitin-protein ligase, were isolated and characterized as altering the mitochondrial/cytosolic distribution of Mod5p. To understand better how competition for the substrate determines the regulation at the molecular level, we analyzed the effect of the rsp5-13 mutation on Erg20p expression.