Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.48 (transcriptase)
 9,479 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study was designed to quantitate cardiac mRNA levels encoding components of the local renin-angiotensin system during the development of volume overload-induced cardiac hypertrophy. Changes in cardiac renin mRNA levels were measured in relation to renin activity in the left ventricle (LV) and in plasma after acute passive stretch of the heart caused by an aortovenocaval shunt in the rat. A quantitative reverse-transcriptase polymerase chain reaction method with competitive internal standards was used to measure mRNA levels in total RNA derived from cardiac tissues after shunt. Seven days after shunt surgery, LV weight was increased by 23%. Renin activities were elevated four- and twofold in plasma and LV, respectively. LV angiotensinogen mRNAs were not significantly increased by shunt surgery; they were twofold higher than phosphoglycerate kinase mRNA from the housekeeping gene PGK-1. By day 7, LV levels for renin mRNA were significantly increased from well below 0.25% to approximately 1% of PGK-1 mRNA. Identity between renin polymerase chain reaction products from kidney and heart cDNAs and absence of "reninlike" amplification products were supported by Southern blotting. Volume overload caused increased expression of the renin gene in the stretched myocardium. This finding is consistent with the concept of a myocardial renin-angiotensin system that can be activated by locally produced renin and contributes to the hypertrophy of cardiac muscle.
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PMID:Stretch-mediated activation of cardiac renin gene. 794 10

The tertiary structure in the 3'-untranslated region (3'-UTR) of Bamboo mosaic virus (BaMV) RNA is known to be involved in minus-strand RNA synthesis. Proteins found in the RNA-dependent RNA polymerase (RdRp) fraction of BaMV-infected leaves interact with the radio labeled 3'-UTR probe in electrophoretic mobility shift assays (EMSA). Results derived from the ultraviolet (UV) cross-linking competition assays suggested that two cellular factors, p43 and p51, interact specifically with the 3'-UTR of BaMV RNA. p43 and p51 associate with the poly(A) tail and the pseudoknot of the BaMV 3'-UTR, respectively. p51-containing extracts specifically down-regulated minus-strand RNA synthesis when added to in vitro RdRp assays. LC/MS/MS sequencing indicates that p43 is a chloroplast phosphoglycerate kinase (PGK). When the chloroplast PKG levels were knocked down in plants, using virus-induced gene silencing system, the accumulation level of BaMV coat protein was also reduced.
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PMID:Chloroplast phosphoglycerate kinase, a gluconeogenetic enzyme, is required for efficient accumulation of Bamboo mosaic virus. 1716 94

Gene expression changes are used with increasing frequency to assess the effects of exposure to environmental agents. Housekeeping (Hk) genes are essential in these analyses as internal controls for normalizing expression levels evaluated with Real-Time PCR (RT-PCR). Ideal Hk genes are constitutively expressed, do not respond to external stimuli and exhibit little or no sample-to-sample or run-to-run variation. Previous studies indicate that some commonly used Hk genes including glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and beta-actin have differential expression in various cell lines. Here we examine the expression of 11 Hk genes in four normal human lymphoblastoid cell lines and one T-cell leukemia (Jurkat) cell line following exposure to graded doses of ionizing radiation or to varying ratio concentrations of phytohemagglutinin (PHA) and phorbol myristate acetate (PMA). PHA and PMA are known to have synergistic effects on the expression of some genes and have very different effects from those of radiation. There has been no systematic study performed to ascertain the best control genes for radiation and/or PHA/PMA exposures in lymphoblastoid cells. Using a two-step reverse-transcriptase RT-PCR protocol we show that following radiation doses ranging from 0 to 400 cGy, 18S rRNA, acidic ribosomal protein, beta-actin, cyclophilin, GAPDH, phosphoglycerokinase, beta-2 microglobulin (B2M), beta-glucuronidase, hypoxanthine phosphoribosyltransferase and transferrin receptor showed no significant variation in expression in normal lymphoblastoid cells. In contrast, only 18S rRNA levels were unchanged in Jurkat cells. After PHA/PMA treatment of the same normal cell lines, B2M showed no significant variation and 18S rRNA, GAPDH and transcription binding protein (TBP) were minimally responsive, whereas in Jurkat cells all these genes were unresponsive. While our results suggest that the utility of a particular Hk gene should be determined for each experimental condition, 18S rRNA and B2M appear to be excellent candidates for use as internal controls in RT-PCR in human lymphoblastoid cells because they have the most constant levels of expression across cell lines following exposure to ionizing radiation as well as to PHA/PMA.
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PMID:Evaluation and validation of housekeeping genes in response to ionizing radiation and chemical exposure for normalizing RNA expression in real-time PCR. 1790 13

The intricate interactions between viruses and hosts include exploitation of host cells for viral replication by using many cellular resources, metabolites and energy. Tomato bushy stunt virus (TBSV), similar to other (+)RNA viruses, induces major changes in infected cells that lead to the formation of large replication compartments consisting of aggregated peroxisomal and ER membranes. Yet, it is not known how TBSV obtains the energy to fuel these energy-consuming processes. In the current work, the authors discovered that TBSV co-opts the glycolytic ATP-generating Pgk1 phosphoglycerate kinase to facilitate the assembly of new viral replicase complexes. The recruitment of Pgk1 into the viral replication compartment is through direct interaction with the viral replication proteins. Altogether, we provide evidence that the ATP generated locally within the replication compartment by the co-opted Pgk1 is used to fuel the ATP-requirement of the co-opted heat shock protein 70 (Hsp70) chaperone, which is essential for the assembly of new viral replicase complexes and the activation of functional viral RNA-dependent RNA polymerase. The advantage of direct recruitment of Pgk1 into the virus replication compartment could be that the virus replicase assembly does not need to intensively compete with cellular processes for access to ATP. In addition, local production of ATP within the replication compartment could greatly facilitate the efficiency of Hsp70-driven replicase assembly by providing high ATP concentration within the replication compartment.
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PMID:Co-opting ATP-generating glycolytic enzyme PGK1 phosphoglycerate kinase facilitates the assembly of viral replicase complexes. 2905 39