Fabiana Carneiro | Universidade Federal do Rio de Janeiro (UFRJ) (original) (raw)

Papers by Fabiana Carneiro

SARS-CoV-2 is the cause of the ongoing COVID-19 pandemic. Here, we investigated the interaction o... more SARS-CoV-2 is the cause of the ongoing COVID-19 pandemic. Here, we investigated the interaction of this new coronavirus with Vero cells using high resolution scanning electron microscopy. Surface morphology, the interior of infected cells and the distribution of viral particles in both environments were observed 2 and 48 hours after infection. We showed areas of viral processing, details of vacuole contents, and viral interactions with the cell surface. Intercellular connections were also approached, and viral particles were adhered to these extensions suggesting direct cell-to-cell transmission of SARS-CoV-2.

Acta Scientific Microbiology

Carneiro and Lucio Ayres Caldas. COVID-19 first cases emerged in Wuhan, China, spreading across o... more Carneiro and Lucio Ayres Caldas. COVID-19 first cases emerged in Wuhan, China, spreading across other countries, culminating in a global pandemic [1]. Regarding the analysis of the clinical characteristics of patients infected with the new coronavirus, although all ages are susceptible, the 12. Giovanetti M., et al. "Molecular Epidemiology of HIV-1 in African Countries: A Comprehensive Overview".

Artificial Organs

Abstract The new coronavirus (2019‐nCoV) or the severe acute respiratory syndrome coronavirus 2 (... more Abstract The new coronavirus (2019‐nCoV) or the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) was officially declared by the World Health Organization (WHO) as a pandemic in March 2020. To date, there are no specific antiviral drugs proven to be effective in treating SARS‐CoV‐2, requiring joint effort from different research fronts to discover the best route of treatment. The first decisions in drug discovery are based on 2D cell culture using high‐throughput screening. In this context, spheroids and organoids emerge as a reliable alternative. Both are scaffold‐free 3D engineered constructs that recapitulate key cellular and molecular events of tissue physiology. Different studies have already shown their advantages as a model for different infectious diseases, including SARS‐CoV‐2 and for drug screening. The use of these 3D engineered tissues as an in vitro model can fill the gap between 2D cell culture and in vivo preclinical assays (animal models) since they could recapitulate the entire viral life cycle. The main objective of this review is to understand spheroid and organoid biology, highlighting their advantages and disadvantages, and how these scaffold‐free engineered tissues can contribute to a better comprehension of viral infection by SARS‐CoV‐2 and to the development of in vitro high‐throughput models for drug screening.

Scientific reports, Jan 28, 2018

The global situation of diseases transmitted by arthropod-borne viruses such as Dengue (DENV), Ye... more The global situation of diseases transmitted by arthropod-borne viruses such as Dengue (DENV), Yellow Fever (YFV), Chikungunya (CHIKV) and Zika (ZIKV) viruses is alarming and treatment of human infection by these arboviruses faces several challenges. The discovery of broad-spectrum antiviral molecules, able to inactivate different groups of viruses, is an interesting approach. The viral envelope is a common structure among arboviruses, being a potential target for antivirals. Porphyrins are amphipathic molecules able to interact with membranes and absorb light, being widely used in photodynamic therapy. Previously, we showed that heme, Co-protoporphyrin IX (CoPPIX) and Sn-protoporphyrin IX (SnPPIX) directly inactivate DENV and YFV infectious particles. Here we demonstrate that the antiviral activity of these porphyrins can be broadened to CHIKV, ZIKV, Mayaro virus, Sindbis virus and Vesicular Stomatitis virus. Porphyrin treatment causes viral envelope protein loss, affecting viral m...

Protein & Peptide Letters, 2009

Membrane fusion is an essential step in the entry of enveloped viruses into their host cells, wha... more Membrane fusion is an essential step in the entry of enveloped viruses into their host cells, what makes it a potentially attractive target for viral inactivation approaches. Fusion is mediated by viral surface glycoproteins that undergo conformational changes triggered by interaction with specific cellular receptors or by the exposition to low pH of endossomal medium. Here we review how several studies on the structural rearrangements of vesicular stomatitis virus (VSV) glycoprotein G during cellular recognition and fusion led us to propose a crucial role of the protonation of His residues for G protein activity. Moreover, we demonstrated that using diethylpyrocarbonate (DEPC), a histidine-modifying compound, it was possible to abolish viral infectivity and pathogenicity in mice, and to elicit neutralizing antibodies that confer protection in these animals against challenge using lethal doses of the virus. The presence of conserved His residues in a wide range of viral fusion proteins and the use of DEPC as a more general means for vaccine development will be also discussed.

Molecular Membrane Biology, 2008

Dengue fever is one of the most widespread tropical diseases in the world. The disease is caused ... more Dengue fever is one of the most widespread tropical diseases in the world. The disease is caused by a virus member of the Flaviviridae family, a group of enveloped positive sense single-stranded RNA viruses. Dengue virus infection is mediated by virus glycoprotein E, which binds to the cell surface. After uptake by endocytosis, this protein induces the fusion between viral envelope and endosomal membrane at the acidic environment of the endosomal compartment. In this work, we evaluated by steady-state and time-resolved fluorescence spectroscopy the interaction between the peptide believed to be the dengue virus fusion peptide and large unilamellar vesicles, studying the extent of partition, fusion capacity and depth of insertion in membranes. The roles of the bilayer composition (neutral and anionic phospholipids), ionic strength and pH of the medium were also studied. Our results indicate that dengue virus fusion peptide has a high affinity to vesicles composed of anionic lipids and that the interaction is mainly electrostatic. Both partition coefficient and fusion index are enhanced by negatively charged phospholipids. The location determined by differential fluorescence quenching using lipophilic probes demonstrated that the peptide is in an intermediate depth in the hemilayers, in-between the bilayer core and its surface. Ultimately, these data provide novel insights on the interaction between dengue virus fusion peptide and its target membranes, namely, the role of oligomerization and specific types of membranes.

Journal of Virology, 2012

Dengue virus (DENV) affects millions of people, causing more than 20,000 deaths annually. No effe... more Dengue virus (DENV) affects millions of people, causing more than 20,000 deaths annually. No effective treatment for the disease caused by DENV infection is currently available, partially due to the lack of knowledge on the basic aspects of the viral life cycle, including the molecular basis of the interaction between viral components and cellular compartments. Here, we characterized the properties of the interaction between the DENV capsid (C) protein and hepatic lipid droplets (LDs), which was recently shown to be essential for the virus replication cycle. Zeta potential analysis revealed a negative surface charge of LDs, with an average surface charge of −19 mV. The titration of LDs with C protein led to an increase of the surface charge, which reached a plateau at +13.7 mV, suggesting that the viral protein-LD interaction exposes the protein cationic surface to the aqueous environment. Atomic force microscopy (AFM)-based force spectroscopy measurements were performed by using C ...

Journal of Virology, 2002

Vesicular stomatitis virus (VSV) infection depends on the fusion of viral and cellular membranes,... more Vesicular stomatitis virus (VSV) infection depends on the fusion of viral and cellular membranes, which is mediated by virus spike glycoprotein G at the acidic environment of the endosomal compartment. VSV G protein does not contain a hydrophobic amino acid sequence similar to the fusion peptides found among other viral glycoproteins, suggesting that membrane recognition occurs through an alternative mechanism. Here we studied the interaction between VSV G protein and liposomes of different phospholipid composition by force spectroscopy, isothermal titration calorimetry (ITC), and fluorescence spectroscopy. Force spectroscopy experiments revealed the requirement for negatively charged phospholipids for VSV binding to membranes, suggesting that this interaction is electrostatic in nature. In addition, ITC experiments showed that VSV binding to liposomes is an enthalpically driven process. Fluorescence data also showed the lack of VSV interaction with the vesicles as well as inhibitio...

Journal of Molecular Biology, 2009

Dengue virus (DV) infection depends on a step of membrane fusion, which occurs in the acidic envi... more Dengue virus (DV) infection depends on a step of membrane fusion, which occurs in the acidic environment of the endosome. This process is mediated by virus surface envelope glycoprotein, in which the loop between residues D98-G112 is considered to be crucial, acting as a fusion peptide. Here, we have characterized functionally and structurally the interaction between the DV fusion peptide and different model membranes by fluorescence and NMR. Its interaction was strongest in dodecylphosphocholine (DPC) micelles and anionic phosphatidylcholine/phosphatidylglycerol vesicles, the only vesicle that was fused by DV fusion peptide. The three-dimensional structure of DV fusion peptide bound to DPC micelles was solved by solution homonuclear NMR with an r.m.s.d. of 0.98 Å. The most striking result obtained from the solution structure was the hydrophobic triad formed by residues W101, L107, and F108, pointing toward the same direction, keeping the segment between G102 and G106 in a loop conformation. The interaction of DV fusion peptide with phosphatidylcholine/phosphatidylglycerol vesicles was also mapped by transfer-nuclear Overhauser enhancement (NOE) experiments, in which the majority of the NOE cross-peaks were from the hydrophobic triad, corroborating the DPCbound structure. Substitution of the residue W101 by an alanine residue completely abolished membrane binding and, thus, fusion by the peptide and its NOE cross-peaks. In conclusion, the 15-residue DV fusion peptide has intrinsic ability to promote membrane fusion, most likely due to the hydrophobic interaction among the residues W101, L107, and F108, which maintains its loop in the correct spatial conformation.

Journal of Biological Chemistry, 2001

Membrane fusion is the key step in the entry of enveloped animal viruses into their host cells. F... more Membrane fusion is the key step in the entry of enveloped animal viruses into their host cells. Fusion of vesicular stomatitis virus with membranes occurs at acidic pH and is mediated by its envelope glycoprotein, the G protein. To study the structural transitions induced by acidic pH on G protein, we have extracted the protein from purified virus by incubation with nonionic detergent. At pH 6.0, purified G protein was able to mediate fusion of either phospholipid vesicles or Vero cells in culture. Intrinsic fluorescence studies revealed that changes in the environment of Trp residues occurred as pH decreases. In the absence of lipidic membranes, acidification led to G protein aggregation, whereas protein-protein interactions were substituted by protein-lipid interactions in the presence of liposomes. 1,1-Bis(4-aniline-5-naphthalene sulfonate) (bis-ANS) binding was utilized to probe the degree of exposure of hydrophobic regions of G protein during acidification. Bis-ANS binding was maximal at pH 6.2, suggesting that a hydrophobic segment is exposed to the medium at this pH. At pH 6.0, a dramatic decrease in bis-ANS binding was observed, probably due to loss of tridimensional structure during the conformational rearrangement. This hypothesis was confirmed by circular dichroism analysis at different pH values, which showed a great decrease in ␣-helix content at pH values close to 6.0, suggesting that a reorganization of G protein secondary structure occurs during the fusion reaction. Our results indicate that G protein undergoes dramatic structural changes at acidic pH and acquires a conformational state able to interact with the target membrane.

Journal of Biological Chemistry, 2003

European Biophysics Journal, 2006

Brazilian Journal of Medical and Biological Research, 2005

Enveloped viruses always gain entry into the cytoplasm by fusion of their lipid envelope with a c... more Enveloped viruses always gain entry into the cytoplasm by fusion of their lipid envelope with a cell membrane. Some enveloped viruses fuse directly with the host cell plasma membrane after virus binding to the cell receptor. Other enveloped viruses enter the cells by the endocytic pathway, and fusion depends on the acidification of the endosomal compartment. In both cases, virus-induced membrane fusion is triggered by conformational changes in viral envelope glycoproteins. Two different classes of viral fusion proteins have been described on the basis of their molecular architecture. Several structural data permitted the elucidation of the mechanisms of membrane fusion mediated by class I and class II fusion proteins. In this article, we review a number of results obtained by our laboratory and by others that suggest that the mechanisms involved in rhabdovirus fusion are different from those used by the two well-studied classes of viral glycoproteins. We focus our discussion on the electrostatic nature of virus binding and interaction with membranes, especially through phosphatidylserine, and on the reversibility of the conformational changes of the rhabdovirus glycoprotein involved in fusion. Taken together, these data suggest the existence of a third class of fusion proteins and support the idea that new insights should emerge from studies of membrane fusion mediated by the G protein of rhabdoviruses. In particular, the elucidation of the three-dimensional structure of the G protein or even of the fusion peptide at different pH's might provide valuable information for understanding the fusion mechanism of this new class of fusion proteins.

Biophysical Journal, 2011

Biophysical Journal, 2013

Biochemical Journal, 2012

Dengue is the major arthropod-borne human viral disease, for which no vaccine or specific treatme... more Dengue is the major arthropod-borne human viral disease, for which no vaccine or specific treatment is available. We used NMR, zeta potential measurements and atomic force microscopy to study the structural features of the interaction between dengue virus C (capsid) protein and LDs (lipid droplets), organelles crucial for infectious particle formation. C protein-binding sites to LD were mapped, revealing a new function for a conserved segment in the N-terminal disordered region and indicating that conformational selection is involved in recognition. The results suggest that the positively charged N-terminal region of C protein prompts the interaction with negatively charged LDs, after which a conformational rearrangement enables the access of the central hydrophobic patch to the LD surface. Taken together, the results allowed the design of a peptide with inhibitory activity of C protein–LD binding, paving the way for new drug development approaches against dengue.