Search results for "1307 Cell Biology"
showing 10 items of 19 documents
Induction of the peroxisome proliferator activated receptor by fenofibrate in rat liver
1992
AbstractThe process of peroxisome proliferation in rodent liver by hypolipidemic compounds and related substances has recently been shown to be receptor-madiated. In the present study, we have examined the effect of oral administration of the strong peroxisome proliferator fenofibrate on the hepatic expression level of the peroxisome proliferator activated receptor (PPAR) in rats. Immunoblots of rat liver cytosols and nuclear extracs using antibodies raised against recombinant PPAR/β-galactosidase fusion proteins revealed a pronounced increase in the amount of PPAR protein in response to fenofibrate treatment. This induction could also be confirmed at the level or RNA by Northern blotting. …
The membrane anchor of microsomal epoxide hydrolase from human, rat, and rabbit displays an unexpected membrane topology.
1997
The microsomal epoxide hydrolase (mEH) and cytochrome P450s catalyze the sequential formation of carcinogenic metabolites. According to one algorithm for predicting the membrane topology of proteins, the human, the rabbit, and the rat mEH should adopt a type II topology. The type II topology is also predicted by a recently established neuronal network which is trained to recognize signal peptides with very high accuracy. In contrast to these predictions we find, based on N-glycosylation analysis in a cell-free and in a cellular system, that the membrane anchor of human, rat, and rabbit mEH displays a type I topology. This result is correctly predicted by the positive inside rule in which ne…
Does dietary salt induce autoimmunity?
2013
Two recent publications suggest that dietary salt may polarize TH17 cells and therefore increase the risk of developing autoimmune disease. Where low salt diets can readily be tested for their therapeutic effects in autoimmune disease, more work is needed to connect dietary salts with the development of immunopathology.
Isolation and characterization of a cDNA encoding rat liver cytosolic epoxide hydrolase and its functional expression in Escherichia coli.
1993
A cDNA of 1992 base pairs encoding the complete rat liver cytosolic epoxide hydrolase has been isolated using a polymerase chain reaction-derived DNA fragment (Arand, M., Knehr, M., Thomas, H., Zeller, H. D., and Oesch, F. (1991) FEBS Lett. 294, 19-22) known to represent the 3'-end of the cytosolic epoxide hydrolase mRNA. Sequence analysis revealed an open reading frame of 1662 nucleotides corresponding to 554 amino acids (M(r) = 62,268). The DNA sequence obtained did not display significant homology to the sequences of microsomal epoxide hydrolase or leukotriene A4 hydrolase or to any other DNA included in the EMBL Data Bank (release 32). On Northern blotting of rat liver RNA, a single mRN…
An impaired peroxisomal targeting sequence leading to an unusual bicompartmental distribution of cytosolic epoxide hydrolase
1991
AbstractTo gain an understanding of the mechanism by which the subcellular distribution of cytosolic epoxide hydrolase (cEH) is directed, we have analyzed the carboxy terminal region of rat liver cEH by means of cDNA cloning to define the structure of its possible peroxisomal targeting sequence (PTS). Purified cEH was subjected to peptide analysis following endoproteinase Glu-C digestion and HPLC-separation of the fragments. The obtained sequence information was used to perform PCR experiments resulting in the isolation of a 680 bp cDNA clone encoding the carboxy terminus of cEH. The deduced amino acid sequence displays a terminal tripeptide Ser-Lys-Ile which is highly homologous to the PTS…
Degradation of phosphatidylethanol counteracts the apparent phospholipase D-mediated formation in heart and other organs.
2003
Phosphatidylalcohols, such as phosphatidylethanol (PEth), are formed from phosphatidylcholine in the presence of a primary alcohol (e.g., ethanol). This 'transphosphatidylation' reaction is used as specific phospholipase D (PLD) assay. Accumulation of PEth in tissues is recognized as a reliable measure of PLD activity, as PEth is allegedly metabolically stable. The general validity of this assumption was reinvestigated in isolated rat heart, small intestine and brain slices. The half-times of 3H-PEth degradation (labelled with 3H-myristic acid and preformed by ethanol exposure for 30 min) were about 1 h in heart and small intestine, but 17 h in brain. As the formation of PEth is superimpose…
Myoglobin, expressed in brown adipose tissue of mice, regulates the content and activity of mitochondria and lipid droplets
2021
Abstract The identification of novel physiological regulators that stimulate energy expenditure through brown adipose tissue (BAT) activity in substrate catalysis is of utmost importance to understand and treat metabolic diseases. Myoglobin (MB), known to store or transport oxygen in heart and skeletal muscles, has recently been found to bind fatty acids with physiological constants in its oxygenated form (i.e., MBO2). Here, we investigated the in vivo effect of MB expression on BAT activity. In particular, we studied mitochondrial function and lipid metabolism as essential determinants of energy expenditure in this tissue. We show in a MB-null (MBko) mouse model that MB expression in BAT i…
NMR Investigation of Structures of G-Protein Coupled Receptor Folding Intermediates
2016
Folding of G-protein coupled receptors (GPCRs) according to the two-stage model (Popot, J. L., and Engelman, D. M. (1990) Biochemistry 29, 4031-4037) is postulated to proceed in 2 steps: partitioning of the polypeptide into the membrane followed by diffusion until native contacts are formed. Herein we investigate conformational preferences of fragments of the yeast Ste2p receptor using NMR. Constructs comprising the first, the first two, and the first three transmembrane (TM) segments, as well as a construct comprising TM1-TM2 covalently linked to TM7 were examined. We observed that the isolated TM1 does not form a stable helix nor does it integrate well into the micelle. TM1 is significant…
Colorimetric quantitation of trace amounts of sodium lauryl sulfate in the presence of nucleic acids and proteins
1992
A fast and sensitive procedure for the colorimetric detection of sodium lauryl sulfate (SDS) is presented. The assay is based upon the formation of a chloroform-extractable ion pair between lauryl sulfate and methylene blue that is quantified spectrophotometrically with an estimated detection limit of 150 ng of SDS. The method is suitable for the monitoring of contaminating traces of SDS in protein or nucleic acid samples that have the potential to interfere with enzymatic manipulations such as proteolytic digest, restriction analysis, or reverse transcription. Since the procedure is extremely simple and no special equipment is required it is accessible to every researcher concerned with SD…
Sequence of a novel cytochrome CYP2B cDNA coding for a protein which is expressed in a sebaceous gland, but not in the liver
1992
The major phenobarbital-inducible rat hepatic cytochromes P-450, CYP2B1 and CYP2B2, are the paradigmatic members of a cytochrome P-450 gene subfamily that contains at least seven additional members. Specific oligonucleotide probes for these genomic members of the CYP2B subfamily were used to assess their tissue-specific expression. In Northern-blot analysis a probe specific to gene 4 (which is designated now as CYP2B12) hybridized to a single mRNA present in the preputial gland, an organ which is used as a model for sebaceous glands, but did not hybridize to mRNA isolated from the liver or from five other tissues of untreated or Aroclor 1254-treated rats. The cDNA sequence for the CYP2B12 R…