A5091904051- RNA and protein synthesis mechanisms
- RNA Research and Splicing
- PI3K/AKT/mTOR signaling in cancer
- Microbial Metabolism and Applications
- RNA modifications and cancer
- Pharmacological Effects of Natural Compounds
- Microbial Natural Products and Biosynthesis
- Viral Infections and Immunology Research
- Ocular Infections and Treatments
- Protein Kinase Regulation and GTPase Signaling
- PARP inhibition in cancer therapy
- Vibrio bacteria research studies
- Ocular Diseases and Behçet’s Syndrome
- Immune Response and Inflammation
- Streptococcal Infections and Treatments
- Ocular Surface and Contact Lens
- Glycosylation and Glycoproteins Research
- Oral microbiology and periodontitis research
- Iron Metabolism and Disorders
- Cancer-related molecular mechanisms research
- Connexins and lens biology
- Bacteriophages and microbial interactions
- DNA and Nucleic Acid Chemistry
- Ion channel regulation and function
- Particle accelerators and beam dynamics
University of Pittsburgh
2012-2022
University of Pittsburgh Medical Center
2012
The 5’terminal oligopyrimidine (5’TOP) motif is a cis-regulatory RNA element located immediately downstream of the 7-methylguanosine [m7G] cap TOP mRNAs, which encode ribosomal proteins and translation factors. In eukaryotes, this coordinates synchronous stoichiometric expression protein components machinery. La-related 1 (LARP1) binds regulating their stability translation. We present crystal structures human LARP1 DM15 region in complex with 5’TOP motif, analog (m7GTP), capped cytidine...
RNA-binding proteins (RBPs) are increasingly identified as post-transcriptional drivers of cancer progression. The RBP LARP1 is an mRNA stability regulator, and elevated expression the protein in hepatocellular lung cancers correlated with adverse prognosis. associates interactome that enriched for oncogenic transcripts. Here we explore role epithelial ovarian cancer, a disease characterized by rapid acquisition resistance to chemotherapy through induction pro-survival signalling. We show,...
Abstract LARP1 is a key repressor of TOP mRNA translation. It binds the m7Gppp cap moiety and adjacent 5′TOP motif mRNAs, thus impeding assembly eIF4F complex on these transcripts. mTORC1 controls translation via LARP1, but details mechanism are unclear. Herein we elucidate by which LARP1’s repression activity. We demonstrate that phosphorylates in vitro vivo, activities efficiently inhibited rapamycin torin1. uncover 26 rapamycin-sensitive phospho-serine -threonine residues distributed 7...
La-related protein 1 (LARP1) regulates the stability of many mRNAs. These include 5′TOPs, mTOR-kinase responsive mRNAs with pyrimidine-rich 5′ UTRs, which encode ribosomal proteins and translation factors. We determined that highly conserved LARP1-specific C-terminal DM15 region human LARP1 directly binds a 5′TOP sequence. The crystal structure this refined to 1.86 Å resolution has three structurally related evolutionarily helix-turn-helix modules within each monomer. motifs resemble HEAT...
Serratia marcescens is a model organism for the study of secondary metabolites. The biologically active pigment prodigiosin (2-methyl-3-pentyl-6-methoxyprodiginine), like many other metabolites, inhibited by growth in glucose-rich medium. Whereas previous studies indicated that this inhibitory effect was pH dependent and did not require cyclic AMP (cAMP), there no information on genes involved mediating phenomenon. Here we used transposon mutagenesis to identify inhibition glucose. Multiple...
Swarming motility and hemolysis are virulence-associated determinants for a wide array of pathogenic bacteria. The broad host-range opportunistic pathogen Serratia marcescens produces serratamolide, small cyclic amino-lipid, that promotes swarming hemolysis. Serratamolide is negatively regulated by the transcription factors HexS CRP. Positive regulators serratamolide production unknown. Similar to antibiotic pigment, prodigiosin, temperature, growth phase, HexS, Because this co-regulation,...
Serratia marcescens is a common contaminant of contact lens cases and lenses. Hemolytic factors S. contribute to the virulence this opportunistic bacterial pathogen. We took advantage an observed hyper-hemolytic phenotype crp mutants investigate mechanisms hemolysis. A genetic screen revealed that swrW necessary for hyper-hemolysis mutants. The gene required biosynthesis biosurfactant serratamolide, previously shown be broad-spectrum antibiotic swarming motility. Multicopy expression or...
Serratia marcescens generates secondary metabolites and secreted enzymes, it causes hospital infections community-acquired ocular infections. Previous studies identified cyclic AMP (cAMP) receptor protein (CRP) as an indirect inhibitor of antimicrobial metabolites. Here, we a putative two-component regulator that suppressed crp mutant phenotypes. Evidence supports the response eepR was directly transcriptionally inhibited by cAMP-CRP. EepR sensor kinase EepS were necessary for biosynthesis...
A case of endophthalmitis following uneventful phacoemulsification and posterior chamber intraocular lens (IOL) implantation in a 77-year-old diabetic man was culture-positive for Enterococcus faecalis. After successful treatment with intravitreal, topical, systemic antibiotic agents, the infection seemed to clear patient achieved corrected visual acuity 20/25. Four months after initial presentation, again developed signs symptoms endophthalmitis, regrowth E The therapy repeated. One month...
Following infection, viruses synthesize nonstructural proteins that mediate viral replication and promote dissemination. Viruses from the family Reoviridae encode are required for formation of progeny viruses. Although different in diverge primary sequence, they functionally homologous appear to facilitate conserved mechanisms dsRNA virus replication. Using vitro cell culture approaches, we found mammalian reovirus protein σNS binds stabilizes RNA is genome synthesis. This work contributes...
The EepR transcription factor positively regulates secondary metabolites and tissue-damaging metalloproteases. To gain insight into mechanisms by which pigment co-regulated factors, genetic suppressor analysis was performed. Suppressor mutations that restored to the non-pigmented ∆eepR mutant mapped hexS ORF. Mutation of also haemolysis, swarming motility protease production eepR mutant. HexS is a known direct negative regulator in Serratia marcescens LysR family an orthologue LrhA. Here, we...
Generation of many useful microbe-derived secondary metabolites, including the red pigment prodigiosin bacterium Serratia marcescens, is inhibited by glucose. In a previous report, genetic approach was used to determine that glucose dehydrogenase activity (GDH) required for inhibiting production and transcription biosynthetic operon (pigA-N). However, factor(s) regulate this process were not characterized. Here we tested hypothesis HexS, LysR-family factor similar LrhA Escherichia coli,...
Abstract The mammalian target of rapamycin complex 1 (mTORC1) controls critical cellular functions such as protein synthesis, lipid metabolism, turnover and ribosome biogenesis through the phosphorylation multiple substrates. In this study, we examined a recently identified mTORC1: La-related (LARP1), member LARP superfamily. Previously, others have shown that LARP1 plays an important role in repressing TOP mRNA translation downstream mTORC1. binds 7-methylguanosine triphosphate (m 7 Gppp)...
Summary Ribosomal defects perturb stem cell differentiation, causing diseases called ribosomopathies. How ribosome levels control differentiation is not fully known. Here, we discovered three RNA helicases are required for biogenesis and Drosophila oogenesis. Loss of these helicases, which named Aramis, Athos Porthos, lead to aberrant stabilization p53, cycle arrest stalled GSC differentiation. Unexpectedly, Aramis efficient translation a cohort mRNAs containing 5’-Terminal-Oligo-Pyrimidine...
Purpose The Serratia marcescens bacterium causes vision-threatening keratitis, life-threatening hospital acquired infections and contaminates contact lens cases. goal of this study was to identify a hemolytic factor produced by keratitis isolates laboratory strains S. marcescens. Methods Hemolysis measured using sheep mouse erythrocytes. mutated with mariner transposon. Hemolysin defective mutants were isolated on blood agar plates. Transposon insertion sites mapped marker rescue sequencing....