82 research outputs found

    RNA Polymerase-Binding and Transcription Initiation Sites Upstream of the Methyl Reductase Operon of Methanococcus vannielii

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    RNA Polymerase, purified from Methanococcus vannielii, was shown by exonuclease III footprinting to bind to a 49-base-pair (bp) region of DNA in the intergenic region upstream of mcrB. Sl nuclease protection experiments demonstrated that transcription Initiation in vivo occurs within this region at 32 or 33 bp 5' to the A T G translation initiation codon of mcrB and 19 or 20 bp 3' to a T A T A box

    A New Look At Some Old Questions In Clinical Electrocardiography

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    Regulation of Human Formyl Peptide Receptor 1 Synthesis: Role of Single Nucleotide Polymorphisms, Transcription Factors, and Inflammatory Mediators

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    The gene encoding the human formyl peptide receptor 1 (FPR1) is heterogeneous, containing numerous single nucleotide polymorphisms (SNPs). Here, we examine the effect of these SNPs on gene transcription and protein translation. We also identify gene promoter sequences and putative FPR1 transcription factors. To test the effect of codon bias and codon pair bias on FPR1 expression, four FPR1 genetic variants were expressed in human myeloid U937 cells fused to a reporter gene encoding firefly luciferase. No significant differences in luciferase activity were detected, suggesting that the translational regulation and protein stability of FPR1 are modulated by factors other than the SNP codon bias and the variant amino acid properties. Deletion and mutagenesis analysis of the FPR1 promoter showed that a CCAAT box is not required for gene transcription. A −88/41 promoter construct resulted in the strongest transcriptional activity, whereas a −72/41 construct showed large reduction in activity. The region between −88 and −72 contains a consensus binding site for the transcription factor PU.1. Mutagenesis of this site caused significant reduction in reporter gene expression. The PU.1 binding was confirmed in vivo by chromatin immunoprecipitation, and the binding to nucleotides −84 to −76 (TTCCTATTT) was confirmed in vitro by an electrophoretic mobility shift assay. Thus, similar to many other myeloid genes, FPR1 promoter activity requires PU.1. Two single nucleotide polymorphisms at −56 and −54 did not significantly affect FPR1 gene expression, despite differences in binding of transcription factor IRF1 in vitro. Inflammatory mediators such as interferon-γ, tumor necrosis factor-α, and lipopolysaccharide did not increase FPR1 promoter activity in myeloid cells, whereas differentiation induced by DMSO and retinoic acid enhanced the activity. This implies that the expression of FPR1 in myeloid cells is developmentally regulated, and that the differentiated cells are equipped for immediate response to microbial infections

    Velocity-resolved reverberation mapping of five bright Seyfert 1 galaxies

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    We present the first results from a reverberation-mapping campaign undertaken during the first half of 2012, with additional data on one AGN (NGC 3227) from a 2014 campaign. Our main goals are (1) to determine the black hole masses from continuum-Hβ reverberation signatures, and (2) to look for velocity-dependent time delays that might be indicators of the gross kinematics of the broad-line region. We successfully measure Hbeta time delays and black hole masses for five AGNs, four of which have previous reverberation mass measurements. The values measured here are in agreement with earlier estimates, though there is some intrinsic scatter beyond the formal measurement errors. We observe velocity dependent Hβ lags in each case, and find that the patterns have changed in the intervening five years for three AGNs that were also observed in 2007.PostprintPeer reviewe

    Distinguishing Voice and Silence at Work: Unique Relationships with Perceived Impact, Psychological Safety, and Burnout

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    Scholars continue to debate whether voice and silence are opposites or distinct constructs. This ambiguity has prevented meaningful theoretical advancements about employees’ voice and silence at work. We draw on the behavioral activation and behavioral inhibition systems perspective to provide a conceptual framework for the independence of voice and silence and explicate how two key antecedents—perceived impact and psychological safety—more strongly relate to voice and silence, respectively. We further differentiate voice and silence by identifying their unique effects on employee burnout. In Study 1, a meta-analysis, we demonstrate that voice and silence are independent (Mρ = -.15) and that perceived impact (psychological safety) relates more strongly to voice (silence) than to silence (voice). We also find that silence has a significantly stronger association with burnout compared to voice. In Study 2, we constructively replicate these findings in an interval-contingent panel study across six months. Taken together, this article shifts the conversation of whether voice and silence are distinct constructs to how they differ and why such differences matter

    Regulating and facilitating : the role of emotional intelligence in maintaining and using positive affect for creativity.

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    Although past research has identified the effects of emotional intelligence on numerous employee outcomes, the relationship between emotional intelligence and creativity has not been well established. We draw upon affective information processing theory to explain how two facets of emotional intelligence — emotion regulation and emotion facilitation — shape employee creativity. Specifically, we propose that emotion regulation ability enables employees to maintain higher positive affect (PA) when faced with unique knowledge processing requirements, while emotion facilitation ability enables employees to use their PA to enhance their creativity. We find support for our hypotheses using a multimethod (ability test, experience sampling, survey) and multisource (archival, self-reported, supervisor-reported) research design of early career managers across a wide range of jobs
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