Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.31 (beta-glucuronidase)
 7,680 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Quantitative gene expression protocols require adequate controls to monitor intersample variation. Quantitative approaches to describe relative changes in gene expression use endogenous controls--"housekeeping" genes. Given the low amounts of mRNA in fat cells, RT-PCR is the method of choice, and housekeeping genes are widely used as endogenous controls. However, literature reports suggest changes in gene expression of typical housekeeping genes (e. g. GAPDH, beta-actin, 18S rRNA) upon hormonal stimulation or during adipogenic differentiation. Thus, we tested the influence of 6 hormones and adipogenic differentiation on gene expression levels of 11 commonly used housekeeping genes in primary cultured mature human adipocytes and preadipocytes. Using the TaqMan RT-PCR technique and "Human Endogenous Control Assays" (PE Biosystems), we found several housekeeping genes with at least twice the difference in expression levels between stimulated and unstimulated cells (such as acidic ribosomal protein, beta-actin, beta(2)-microglobulin and beta-glucuronidase). Only GAPDH and transferrin receptor gene expression levels did not change under any of the stimuli tested, thus appeared best suited for gene expression studies in human adipose cells across a wide range of experimental settings.
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PMID:Validation of endogenous controls for gene expression studies in human adipocytes and preadipocytes. 1160 84

Real-time reverse transcription PCR (RT-PCR) is a sensitive and accurate method to monitor gene expression and is often used to profile the expression of putative tumor antigens in the context of immunotherapy. However, this technique consists of several steps, including cell processing, RNA extraction, RNA storage, assessment of RNA concentration, and cDNA synthesis prior to PCR. To compensate for potential variability introduced in this procedure, the expression of housekeeping genes is commonly assessed in parallel with the expression of the gene of interest. In this study, the expression of a variety of housekeeping genes in a panel of 26 different human tumor and embryonal cell lines was assessed using real-time RT-PCR. For some control genes, the variability in expression was significant between different cell lines, despite the equalization of quantities of input RNA. The greatest variability was found for GAPDH. The lowest variability was found for beta-glucuronidase (GUS) and 18S rRNA. While real-time RT-PCR is a powerful tool for gene expression analysis, these results suggest that the choice of control genes to normalize the expression of the gene of interest is critical to the interpretation of experimental results and should be tailored to the nature of the study.
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PMID:Selection of appropriate control genes to assess expression of tumor antigens using real-time RT-PCR. 1474 Apr 90

Selection of appropriate housekeeping genes (HKG) for normalization of quantitative PCR data for genes of interest is critical for interpretation of results. Ideally, copy number of the chosen HKG mRNA will not vary with experimental treatments or physiological state in the tissue studied, which improves accuracy in detecting changes in genes of interest. Because of the liver's dynamic role in metabolism, physiological state or dietary treatments could alter mRNA expression of commonly used HKG. Therefore, the objective of this study was to evaluate stability of mRNA expression for a number of candidate HKG in bovine liver across different physiological and dietary experimental conditions during the periparturient period. A publicly available program (geNorm) was used to evaluate expression stability of 8 HKG (beta-actin, glyceraldehyde 3-phosphate dehydrogenase, beta-glucuronidase, peptidylprolyl isomerase A, polyubiquitin, ribosomal protein S9, ribosomal protein L32, and 18S ribosomal RNA) in 91 liver RNA samples. Screened samples included liver from cows in 3 groups: 1) cows receiving a dietary supplement pre- and postpartum (n = 10); 2) cows with clinical or subclinical ketosis (n = 7); and 3) cows consuming different amounts of energy prepartum (n = 74). In group 3, samples from d -65, -30, -14, 1, 14, 28, and 49 relative to parturition were included to enable characterization of HKG mRNA expression across different physiological states. Initial analyses indicated that mRNA for ribosomal protein S9 (RPS9) was one of the most stably expressed across different experiment types. To determine the best gene, 200 bootstrap replications of the original data set were performed to determine if the ranking of RPS9 was superior to the other 7 genes evaluated. Average ranks and estimated standard errors for the top 3 genes were 1.64 +/- 0.06, 3.27 +/- 0.10, and 3.71 +/- 0.12 for RPS9, GAPDH, and beta-actin, respectively. Ribosomal protein S9 was ranked first 59% of the time and was never ranked lower than fifth. The lowest-ranked gene was polyubiquitin, ranked last 46.5% of the time (average rank = 6.85 +/- 0.10). In this study, physiological state, amount of intake, or dietary treatment influenced the mRNA expression of commonly used HKG in bovine liver. Ideally, expression stability should be tested before collection of data in all experiments; however, we have shown that RPS9 mRNA is stable across several physiological and diet-related experimental conditions for dairy cows, making it a good HKG in liver quantitative PCR experiments.
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PMID:Housekeeping gene expression in bovine liver is affected by physiological state, feed intake, and dietary treatment. 1743 Sep 24