A5038017063- Hepatitis C virus research
- Hepatitis B Virus Studies
- Monoclonal and Polyclonal Antibodies Research
- Liver Disease Diagnosis and Treatment
- HIV/AIDS drug development and treatment
- SARS-CoV-2 and COVID-19 Research
- Histone Deacetylase Inhibitors Research
- Peptidase Inhibition and Analysis
- Viral Infections and Immunology Research
- Chromatin Remodeling and Cancer
- Epigenetics and DNA Methylation
- COVID-19 Clinical Research Studies
- Biochemical and Molecular Research
- Protein purification and stability
- Systemic Lupus Erythematosus Research
- Protein Degradation and Inhibitors
- Animal Virus Infections Studies
- Chemical Synthesis and Analysis
- vaccines and immunoinformatics approaches
- interferon and immune responses
- Influenza Virus Research Studies
- Immunotherapy and Immune Responses
- Liver Diseases and Immunity
- Viral gastroenteritis research and epidemiology
- Genomics and Chromatin Dynamics
University of Milan
1985-2025
Istituto Nazionale Genetica Molecolare
2015-2024
Sapienza University of Rome
2013-2024
Policlinico Umberto I
2024
Ospedale Vito Fazzi
2024
California Institute of Technology
2022
Istituti di Ricovero e Cura a Carattere Scientifico
2021
Ospedale Sacro Cuore Don Calabria
2019
Hospital Universitario Fundación Jiménez Díaz
2016
Institute of Molecular Bioimaging and Physiology
2014
Histone deacetylases (HDACs) are a family of enzymes involved in the regulation gene expression, DNA repair, and stress response. These processes often altered tumors, HDAC inhibitors have had pronounced antitumor activity with promising results clinical trials. Here, we report crystal structure human HDAC8 complex hydroxamic acid inhibitor. Such eukaryotic zinc-dependent has not be described previously. Similar to bacterial HDAC-like protein, folds single alpha/beta domain. The inhibitor...
We report the crystal structure of RNA-dependent RNA polymerase hepatitis C virus, a major human pathogen, to 2.8-A resolution. This enzyme is key target for developing specific antiviral therapy. The catalytic domain contains 531 residues folded in characteristic fingers, palm, and thumb subdomains. fingers subdomain region, "fingertips," that shares same fold with reverse transcriptases. Superposition available structures latter shows from palm fingertips are structurally equivalent. In...
Previous findings have suggested that class IIa histone deacetylases (HDACs) (HDAC4, -5, -7, and -9) are inactive on acetylated substrates, thus differing from I IIb enzymes. Here, we present evidence supporting this view demonstrate HDACs very inefficient enzymes standard substrates. We identified HDAC inhibitors unable to bind recombinant human HDAC4 while showing inhibition in a typical enzymatic assay, suggesting the observed activity rather reflects involvement of endogenous copurified...
Hepatitis C virus (HCV) possesses a positive-sense RNA genome which encodes large polyprotein of 3,010 amino acids. Previous data and sequence analysis have indicated that this is processed by cellular proteases possibly virally encoded serine protease localized in the N-terminal domain nonstructural protein NS3. To characterize molecular aspects HCV biogenesis to clearly identify products derived from genome, we examined expression using vaccinia T7 transient system transfected cells...
The proteolytic cleavages at the NS3-NS4A, NS4A-NS4B, NS4B-NS5A, and NS5A-NS5B junctions of hepatitis C virus (HCV) polyprotein are effected by virus-encoded serine protease contained within NS3. Using transient expression in HeLa cells cDNA fragments that code for regions HCV polyprotein, we studied whether viral functions other than NS3 required processing these sites. We found that, addition to NS3, a C-terminal 33-amino-acid sequence NS4A protein is cleavage NS3-NS4A NS4B-NS5A sites it...
Histone deacetylases (HDACs) regulate chromatin status and gene expression, their inhibition is of significant therapeutic interest. To date, no biological substrate for class IIa HDACs has been identified, only low activity on acetylated lysines demonstrated. Here, we describe inhibitor-bound inhibitor-free structures the histone deacetylase-4 catalytic domain (HDAC4cd) an HDAC4cd active site mutant with enhanced enzymatic toward lysines. The presented, coupled data, provide molecular basis...
Characterization of the immune responses to SARS-CoV-2 reveals a CD8 + T cell subset that likely establishes memory virus.
The development of a tractable small animal model faithfully reproducing human coronavirus disease 2019 pathogenesis would arguably meet pressing need in biomedical research. Thus far, most investigators have used transgenic mice expressing the ACE2 epithelial cells (K18-hACE2 mice) that are intranasally instilled with liquid severe acute respiratory syndrome 2 (SARS-CoV-2) suspension under deep anesthesia. Unfortunately, this experimental approach results disproportionate high central...
Abstract Vaccines have reduced severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) morbidity and mortality, yet emerging variants challenge their effectiveness. The prevailing approach to updating vaccines targets the antibody response, operating under presumption that it is primary defense mechanism following vaccination or infection. This perspective, however, can overlook role of T cells, particularly when levels are low absent. Here we show, through studies in mouse models...
ABSTRACT We report here the results of a systematic high-resolution X-ray crystallographic analysis complexes hepatitis C virus (HCV) RNA polymerase with ribonucleoside triphosphates (rNTPs) and divalent metal ions. An unexpected observation revealed by this study is existence specific rGTP binding site in shallow pocket at molecular surface enzyme, 30 Å away from catalytic site. This previously unidentified pocket, which lies interface between fingers thumb, may be an allosteric regulatory...
The RNA-dependent RNA polymerase (NS5B) of hepatitis C virus (HCV) is essential for the replication viral and thus constitutes a valid target chemotherapeutic intervention HCV infection. In this report, we describe identification 2'-substituted nucleosides as inhibitors replication. 5'-triphosphates 2'-C-methyladenosine 2'-O-methylcytidine are found to inhibit NS5B-catalyzed synthesis in vitro, manner that competitive with substrate nucleoside triphosphate. NS5B able incorporate either...
The urgent need for efficacious drugs to treat chronic hepatitis C virus (HCV) infection requires a concerted effort develop inhibitors specific virally encoded enzymes. We demonstrate that 2′-C-methyl ribonucleosides are efficient chain-terminating of HCV genome replication. Characterization drug-resistant replicons defined single S282T mutation within the active site viral polymerase conferred loss sensitivity structurally related compounds in both replicon and isolated assays. Biochemical...
Abstract The crystal structure of the NS3 protease hepatitis C virus (BK strain) has been determined in space group P6 3 22 to a resolution 2.2 Å. This is bound with 14‐mer peptide representing central region NS4A protein. There are two molecules 1_180 ‐NS4A 21′‐34′ complex per asymmetric unit. Each displays familiar chymotrypsin‐like fold that includes β‐barrel domains and four short α‐helices. catalytic triad (Ser‐139, His‐57, Asp‐81) located crevice between domains. forms an almost...
The nonstructural protein NS3 of the hepatitis C virus (HCV) harbors a serine protease domain that is responsible for most processing events region polyprotein. Its inhibition presently regarded as promising strategy coping with disease caused by HCV. In this work, we show undergoes N-terminal cleavage products substrate peptides corresponding to NS4A-NS4B, NS4B-NS5A, and NS5A-NS5B sites, whereas no observed product intramolecular NS3-NS4A junction. Ki values hexamer inhibitory [Ki(NS4A) =...
ABSTRACT The hepatitis C virus (HCV) nonstructural 3 protein (NS3) contains at least two domains associated with multiple enzymatic activities; a serine protease activity resides in the N-terminal one-third of protein, whereas RNA helicase and RNA-stimulated nucleoside triphosphatase are C-terminal portion. To study possible mutual influence these activities, full-length NS3 polypeptide 67 kDa was expressed as nonfusion Escherichia coli , purified to homogeneity, shown retain all three...
ABSTRACT The RNA-dependent RNA polymerase of hepatitis C virus (HCV) is the catalytic subunit viral amplification machinery and an appealing target for development new therapeutic agents against HCV infection. Nonnucleoside inhibitors based on a benzimidazole scaffold have been recently reported. Compounds this class are efficient replication in cell culture, thus providing attractive candidates further development. Here we report detailed analysis mechanism action selected inhibitors....
Mutations within PCSK9 (proprotein convertase subtilisin/kexin type 9) are associated with dominant forms of familial hyper- and hypocholesterolemia. Although controls low density lipoprotein (LDL) receptor (LDLR) levels post-transcriptionally, several questions concerning its mode action remain unanswered. We show that purified protein added to the medium human endothelial kidney 293, HepG2, Chinese hamster ovary cell lines decreases cellular LDL uptake in a dose-dependent manner. Using...