Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.4.2.8 (hypoxanthine-guanine phosphoribosyltransferase)
 2,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Various "housekeeping" genes are often used as endogenous controls in gene expression experiments. We have cloned from swine, three genes commonly used as endogenous controls in other species and have characterized their relative levels of expression in various porcine tissues and their response to various cell activators. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and beta-actin were readily detected by northern hybridization in various tissues and in alveolar macrophages. The expression of hypoxanthine phosphoribosyltransferase (HPRT) was detected only by northern hybridization of poly-A+ enriched RNA and by reverse transcriptase-polymerase chain reaction (RT-PCR), making it more suitable for highly sensitive detection methods. Expression of GAPDH varied less among tissues than did beta-actin, making it more useful control for comparisons of gene expression between tissues with northern hybridizations. Various treatments of cultured alveolar macrophages differentially affected levels of beta-actin and GAPDH, while HPRT expression was unchanged in alveolar macrophages or spleen cells similarly treated. Therefore, while HPRT can be used as the endogenous control with sensitive detection methods such as RT-PCR, less sensitive detection methods require a more abundant gene such as GAPDH.
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PMID:Regulation of hypoxanthine phosphoribosyltransferase, glyceraldehyde-3-phosphate dehydrogenase and beta-actin mRNA expression in porcine immune cells and tissues. 967 36

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) has long been used as a default reference gene in quantitative mRNA profiling experiments. However, its expression reportedly varies in response to a range of pathophysiological variables (inflammation, oxidative stress, hyperinsulinaemia, hypoxia) which feature prominently in sepsis. We therefore assessed the applicability of using GAPDH as a reference gene for expression studies in sepsis compared to other housekeeping genes (succinate dehydrogenase complex subunit A (SDHA), hypoxanthine phosphoribosyltransferase (HPRT)-1). Severe sepsis resulted in a 42.4-fold increase in median GAPDH expression (P<0.001), whereas median HPRT expression was raised more modestly (2.9-fold; P<0.001), and there was no significant difference in SDHA expression between sepsis and control patients. HPRT was identified by NormFinder to be the most stably expressed single gene. In order to assess the impact of this variability on data interpretation, interleukin (IL)-10 expression was normalised separately to GAPDH and to the geometric mean of HPRT and SDHA. In the former case, there was no significant difference in IL-10 expression between controls and septic patients, whilst in the latter, a significant 8.5-fold increase in median IL-10 expression was noted (P<0.001). GAPDH is thus an unreliable housekeeping gene for normalising gene expression in sepsis which should be replaced by alternative, validated reference genes.
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PMID:Glyceraldehyde-3-phosphate dehydrogenase is an inappropriate housekeeping gene for normalising gene expression in sepsis. 2485 25