transcriptional regulation
Research Article | Molecular Biology and PhysiologyAtrR Is an Essential Determinant of Azole Resistance in Aspergillus fumigatusAspergillus fumigatus is the major filamentous fungal pathogen in humans. Infections associated with A. fumigatus are often treated with azole drugs, but resistance to these antifungal agents is increasing. Mortality from aspergillosis associated with azole-resistant fungi is extremely high....
Research Article | Molecular Biology and PhysiologyBldC Delays Entry into Development To Produce a Sustained Period of Vegetative Growth in Streptomyces venezuelaeUnderstanding the mechanisms that drive bacterial morphogenesis depends on the dissection of the regulatory networks that underpin the cell biological processes involved. Recently, Streptomyces venezuelae has emerged as an attractive model system for the study of morphological differentiation in Streptomyces. This has led to significant progress in...
Research Article | Molecular Biology and PhysiologyPAS Domain Protein Pas3 Interacts with the Chromatin Modifier Bre1 in Regulating Cryptococcal MorphogenesisFor the ubiquitous environmental pathogen Cryptococcus neoformans, the morphological transition from yeast to filament confers resistance to natural predators like soil amoeba and is an integral differentiation event to produce infectious spores. Interestingly, filamentation is immuno-stimulatory and attenuates cryptococcal virulence in a mammalian host. Consistently...
- Research ArticleDefining the DNA Binding Site Recognized by the Fission Yeast Zn2Cys6 Transcription Factor Pho7 and Its Role in Phosphate Homeostasis
Fungi respond to phosphate starvation by inducing the transcription of a set of phosphate acquisition genes that comprise a phosphate regulon. Pho7, a member of the Zn2Cys6 family of fungal transcription regulators, is the central player in the phosphate starvation response in fission yeast. The present study identifies a 12-nucleotide Pho7 DNA binding motif [5′-TCG(G/C)(A/T)xxTTxAA] in the promoters of phosphate-...
- Editor's Pick Research ArticleAlternative Evolutionary Pathways for Drug-Resistant Small Colony Variant Mutants in Staphylococcus aureus
Small colony variants (SCVs) of Staphylococcus aureus are a significant clinical problem, causing persistent and antibiotic-resistant infections. However, SCVs are unstable and can rapidly evolve growth-compensated mutants. Previous data suggested that growth compensation only occurred with the loss of antibiotic resistance. We have used selection with serial passaging to uncover four distinct pathways of growth compensation...
- Research ArticleA Herpesviral Immediate Early Protein Promotes Transcription Elongation of Viral Transcripts
HSV-1 interacts with many cellular proteins throughout productive infection. Here, we demonstrate the interaction of a viral protein, ICP22, with a subset of cellular proteins known to be involved in transcription elongation. We determined that ICP22 is required to recruit the FACT complex and other transcription elongation factors to viral genomes and that in the absence of ICP22 viral transcription is globally reduced late in...
- Research ArticleViral DNA Replication Orientation and hnRNPs Regulate Transcription of the Human Papillomavirus 18 Late Promoter
It has been known for decades that the activity of viral late promoters is associated with viral DNA replication among almost all DNA viruses. However, the mechanism of how DNA replication activates the viral late promoter and what components of the replication machinery are involved remain largely unknown. In this study, we characterized the P811 promoter region of HPV18 and demonstrated that its activation depends on the...
- Research ArticleQuantitative Kinetic Analyses of Shutting Off a Two-Component System
Activation of TCSs has been extensively studied; however, the kinetics of shutting off TCS pathways is not well characterized. We present comprehensive analyses of the shutoff response for the PhoR-PhoB system that reveal the impact of phosphatase activity on shutoff kinetics. This allows development of a quantitative framework not only to characterize the phosphatase activity in the natural cellular environment but also to understand...