Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.6 (RNA polymerase)
 34,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Real-time PCR is a highly sensitive, relatively easy to perform assay for quantifying mRNA abundance. However, there are several complexities built into the assay that can affect data interpretation. Most notably, the selection of an appropriate internal control for normalization is essential for expression data interpretation. In this study we investigated the suitability of seven commonly used genes [18S ribosomal RNA (18S), alpha tubulin (TUBA), beta actin (ACTB), beta-2 microglobulin (B2M), embryonic elongation factor-1 alpha (EEF1A), glyceraldehyde phosphate dehydrogenase (GAPDH), and RNA polymerase II polypeptide B (POLR2B)] as potential quantitative references for normalizing real-time PCR data generated in the study of channel catfish physiology. Gene expression and stability were evaluated among 15 channel catfish tissues and within physiologically-relevant tissues in response to experimental manipulation (i.e. LHRH injection, fasting, and acute stress). Expression of the seven candidate reference genes varied across all tissue types tested, indicating that none of the genes could suitably serve as reference genes for cross tissue comparisons. Experimentally altering the physiological state of the fish differentially affected expression of the various reference genes depending on experimental design and tissue type, with 18S unaffected by the experimental treatment in all tissues examined. For example, the selection of a differentially expressed gene, GAPDH, as opposed to 18S, to normalize hepatic growth hormone receptor during fasting resulted in misinterpretation of the data. These results reveal the importance of providing comprehensive details of reference gene validation when publishing real-time PCR results, with this manuscript serving as a basic guideline for reference gene selection in channel catfish research.
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PMID:Stability of reference genes for real-time PCR analyses in channel catfish (Ictalurus punctatus) tissues under varying physiological conditions. 1869 90

RNA polymerase II (RNAPII), the 12-subunit enzyme that synthesizes all mRNAs and several non-coding RNAs in eukaryotes, plays a central role in cell function. Although multiple proteins are known to regulate the activity of RNAPII during transcription, little is known about the machinery that controls the fate of the enzyme before or after transcription. We used systematic protein affinity purification coupled to mass spectrometry (AP-MS) to characterize the high resolution network of protein interactions of RNAPII in the soluble fraction of human cell extracts. Our analysis revealed that many components of this network participate in RNAPII biogenesis. We show here that RNAPII-associated protein 4 (RPAP4/GPN1) shuttles between the nucleus and the cytoplasm and regulates nuclear import of POLR2A/RPB1 and POLR2B/RPB2, the two largest subunits of RNAPII. RPAP4/GPN1 is a member of a newly discovered GTPase family that contains a unique and highly conserved GPN loop motif that we show is essential, in conjunction with its GTP-binding motifs, for nuclear localization of POLR2A/RPB1 in a process that also requires microtubule assembly. A model for RNAPII biogenesis is presented.
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PMID:The protein interaction network of the human transcription machinery reveals a role for the conserved GTPase RPAP4/GPN1 and microtubule assembly in nuclear import and biogenesis of RNA polymerase II. 2085 44