Search results for " transporters"
showing 10 items of 194 documents
Engineering of sugar transporters for improvement of xylose utilization during high-temperature alcoholic fermentation in Ogataea polymorpha yeast
2020
Abstract Background Xylose transport is one of the bottlenecks in the conversion of lignocellulosic biomass to ethanol. Xylose consumption by the wild-type strains of xylose-utilizing yeasts occurs once glucose is depleted resulting in a long fermentation process and overall slow and incomplete conversion of sugars liberated from lignocellulosic hydrolysates. Therefore, the engineering of endogenous transporters for the facilitation of glucose-xylose co-consumption is an important prerequisite for efficient ethanol production from lignocellulosic hydrolysates. Results In this study, several engineering approaches formerly used for the low-affinity glucose transporters in Saccharomyces cerev…
TAP-polymorphisms in juvenile onset psoriasis and psoriatic arthritis.
1996
Abstract Juvenile onset psoriasis is strongly associated with the HLA-class I genes Cw6 and B57 whereas patients with psoriatic arthritis show an increased frequency of HLA-B27. It is unclear whether additional major histocompatibility genes also increase disease susceptibility. The TAP genes (transporter associated with antigen processing) encode two membrane-spanning proteins that translocate antigenic peptides from the cytoplasm into the endoplasmic reticulum. Comparison of 60 patients with juvenile onset psoriasis, 63 psoriatic arthritis patients, and 101 caucasoid controls revealed an increase of the TAP1 ∗ 0101 allele in the psoriasis group, that could not be explained by linkage to o…
Multixenobiotic resistance efflux activity in Daphnia magna and Lumbriculus variegatus
2014
Multixenobiotic resistance is a phenomenon in which ATP-binding cassette (ABC) family proteins transfer harmful compounds out of cells. Daphnia magna and Lumbriculus variegatus are model species in aquatic ecotoxicology, but the presence and activity of ABC proteins have not been well described in these species. The aim of this work was to study the presence, activity, and inhibition of ABC transport proteins in D. magna and L. variegatus. The presence of abcb1 and abcc transcripts in 8-9-day-old D. magna was investigated by qRT-PCR. The activity of MXR in D. magna and L. variegatus was explored by influx of the fluorescent ABC protein substrates rhodamine B and calcein-AM, with and without…
Antigen-processing machinery breakdown and tumor growth.
2000
Defects in the major histocompatibility complex (MHC) class I antigen-processing machinery (APM) have been described in tumors of different histology. Murine data suggest that defects in the MHC class II APM might also be associated with malignant transformation of human cells. This article describes the pathophysiology of the MHC class I and II APM, reviews APM abnormalities in tumor cells and discusses their role in the escape of tumor cells from in vitro recognition by T cells.
Impact ofABCsingle nucleotide polymorphisms upon the efficacy and toxicity of induction chemotherapy in acute myeloid leukemia
2016
Anthracycline uptake could be affected by efflux pumps of the ABC family. The influence of 7 SNPs of ABC genes was evaluated in 225 adult de novo acute myeloid leukemia (AML) patients. After multivariate logistic regression there were no significant differences in complete remission, though induction death was associated to ABCB1 triple variant haplotype (p = .020). The ABCB1 triple variant haplotype was related to higher nephrotoxicity (p = .016), as well as this haplotype and the variant allele of ABCB1 rs1128503, rs2032582 to hepatotoxicity (p = .001; p = .049; p .001). Furthermore, the variant allele of ABCC1 rs4148350 was related to severe hepatotoxicity (p = .044), and the variant al…
Both cholestatic and steatotic drugs trigger extensive alterations in the mRNA level of biliary transporters in rat hepatocytes: Application to devel…
2016
Disruption of the vectorial bile acid transport in the liver is a key feature of cholestatic drugs, although many causal and mechanistic aspects are still unknown. The aim of the present study was to explore if cholestatic drugs can repress or induce the expression of hepatic transporters. To this end, sandwich-cultured rat hepatocytes were treated with cholestatic and non-cholestatic (steatotic, non-hepatotoxic, etc.) drugs and the mRNA expression of 10 uptake and efflux biliary transporters was measured. Results evidenced that all cholestatic drugs cause extensive alterations in the mRNA expression of most biliary transporters. Surprisingly, nearly all steatotic drugs also affected the ex…
Anti-hyperuricemic and nephroprotective effects of extracts from Chaenomeles sinensis (Thouin) Koehne in hyperuricemic mice
2018
Clinically, Chaenomeles sinensis (Thouin) Koehne (C. sinensis) has been used to treat hyperuricemia and gout. However, the exact mechanism of action is still unknown. In the present study, the ethyl acetate fraction of C. sinensis fruit extract (CSF-E) was separated. Potassium oxonate (PO)-induced hyperuricemic mice and normal mice were administered with CSF-E at 60, 120 and 180 mg kg-1, respectively for 7 days. Serum uric acid, creatinine and BUN levels, liver oxidative damage, and serum and hepatic XOD activities were primarily measured using assay kits. The evaluation of its nephroprotective effects was carried out by renal histopathological analysis. Simultaneously, renal protein levels…
Effect of dietary polyunsaturated fatty acids on the expression of peroxisomal ABC transporters
2008
Abstract Peroxisomal ABC transporters encoded by the ABCD genes are thought to participate in the import of specific fatty acids in the peroxisomal matrix. ABCD1 deficiency is associated with X-linked adrenoleukodystrophy (X-ALD), the most frequent peroxisomal disorder which is characterized by the accumulation of saturated very-long-chain fatty acids (VLCFA). ABCD2 (the closest homolog of ABCD1) and ABCD3 have been shown to have partial functional redundancy with ABCD1; only when overexpressed, they can compensate for VLCFA accumulation. Other lipids, for instance polyunsaturated fatty acids (PUFA), should be possible candidate substrates for the ABCD2 and ABCD3 gene products, ALDRP and PM…
Behavioral Effects of GABAA Receptor Stimulation and GABA-Transporter Inhibition
2000
Abstract The present analysis addressed behavioral changes after treatment with 4.5 mg/kg or 18.5 mg/kg of the GABA-uptake inhibitor tiagabine combined with either the benzodiazepine diazepam (1.5 mg/kg) or the imidazopyridine zolpidem (0.05 mg/kg), the latter two acting differentially on GABA A receptor subtypes. The study included 97 male PVG/OIaHsd rats. A standard open field, an enriched open field, and an elevated plus-maze was used to study rat behavior. Treatment with the low dose of tiagabine alone induced no specific behavioral effects, whereas the high dose had an anxiolytic-like potential. Furthermore, diazepam but not zolpidem displayed anxiolytic-like effects. Combination of ea…
A conserved role for the mitochondrial citrate transporter Sea/SLC25A1 in the maintenance of chromosome integrity.
2009
Histone acetylation plays essential roles in cell cycle progression, DNA repair, gene expression and silencing. Although the knowledge regarding the roles of acetylation of histone lysine residues is rapidly growing, very little is known about the biochemical pathways providing the nucleus with metabolites necessary for physiological chromatin acetylation. Here, we show that mutations in the scheggia (sea)-encoded Sea protein, the Drosophila ortholog of the human mitochondrial citrate carrier Solute carrier 25 A1 (SLC25A1), impair citrate transport from mitochondria to the cytosol. Interestingly, inhibition of sea expression results in extensive chromosome breakage in mitotic cells and indu…