ORCID Profile
0000-0001-7289-2093
Current Organisation
Evotec (United Kingdom)
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: Wiley
Date: 02-02-2019
Abstract: Scribble (SCRIB) is an important adaptor protein that controls the establishment and maintenance of apico-basal cell polarity. To better understand how SCRIB controls cell polarity signalling via its PDZ domains, we investigated human SCRIB interactions with adenomatous polyposis coli (APC). We show that SCRIB PDZ1, PDZ2 and PDZ3 are the major interactors with the APC PDZ-binding motif (PBM), whereas SCRIB PDZ4 does not show detectable binding to APC. We then determined the crystal structure of SCRIB PDZ1 domain bound to the APC PBM. Our findings reveal a previously unreported pattern of interactions between the SCRIB PDZ domain region with the C-terminal PDZ binding motif of APC, where SCRIB PDZ1 domain is the highest affinity site.
Publisher: American Society for Microbiology
Date: 15-03-2017
DOI: 10.1128/JVI.02228-16
Abstract: Programmed cell death is a tightly controlled process critical for the removal of damaged or infected cells. Pro- and antiapoptotic proteins of the Bcl-2 family are pivotal mediators of this process. African swine fever virus (ASFV) is a large DNA virus, the only member of the Asfarviridae family, and harbors A179L, a putative Bcl-2 like protein. A179L has been shown to bind to several proapoptotic Bcl-2 proteins however, the hierarchy of binding and the structural basis for apoptosis inhibition are currently not understood. We systematically evaluated the ability of A179L to bind proapoptotic Bcl-2 family members and show that A179L is the first antiapoptotic Bcl-2 protein to bind to all major death-inducing mammalian Bcl-2 proteins. We then defined the structural basis for apoptosis inhibition of A179L by determining the crystal structures of A179L bound to both Bid and Bax BH3 motifs. Our findings provide a mechanistic understanding for the potent antiapoptotic activity of A179L by identifying it as the first panprodeath Bcl-2 binder and serve as a platform for more-detailed investigations into the role of A179L during ASFV infection. IMPORTANCE Numerous viruses have acquired strategies to subvert apoptosis by encoding proteins capable of sequestering proapoptotic host proteins. African swine fever virus (ASFV), a large DNA virus and the only member of the Asfarviridae family, encodes the protein A179L, which functions to prevent apoptosis. We show that A179L is unusual among antiapoptotic Bcl-2 proteins in being able to physically bind to all core death-inducing mammalian Bcl-2 proteins. Currently, little is known regarding the molecular interactions between A179L and the proapoptotic Bcl-2 members. Using the crystal structures of A179L bound to two of the identified proapoptotic Bcl-2 proteins, Bid and Bax, we now provide a three-dimensional (3D) view of how A179L sequesters host proapoptotic proteins, which is crucial for subverting premature host cell apoptosis.
Publisher: Springer Science and Business Media LLC
Date: 12-01-2017
Abstract: Sponges of the porifera family harbor some of the evolutionary most ancient orthologs of the B-cell lymphoma-2 (Bcl-2) family, a protein family critical to regulation of apoptosis. The genome of the sponge Geodia cydonium contains the putative pro-survival Bcl-2 homolog BHP2, which protects sponge tissue as well as mammalian Hek-293 and NIH-3T3 cells against erse apoptotic stimuli. The Lake Baikal demosponge Lubomirskia baicalensis has been shown to encode both putative pro-survival Bcl-2 (LB-Bcl-2) and pro-apoptotic Bcl-2 members (LB-Bak-2), which have been implied in axis formation (branches) in L. baicalensis. However, the molecular mechanism of action of sponge-encoded orthologs of Bcl-2 remains to be clarified. Here, we report that the pro-survival Bcl-2 ortholog BHP2 from G. cydonium is able to bind the BH3 motif of a pro-apoptotic Bcl-2 protein, LB-Bak-2 of the sponge L. baicalensis . Furthermore, we determined the crystal structure of BHP2 bound to LB-Bak-2, which revealed that using a binding groove conserved across all pro-survival Bcl-2 proteins, BHP2 binds multi-motif Bax-like proteins through their BH3-binding regions. However, BHP2 discriminates against BH3-only bearing proteins by blocking access to a hydrophobic pocket that is critical for BH3 motif binding in pro-survival Bcl-2 proteins from higher organisms. This differential binding mode is reflected in a structure-based phylogenetic comparison of BHP2 with other Bcl-2 family members, which revealed that BHP2 does not cluster with either Bcl-2 members of higher organisms or pathogen-encoded homologs, and assumes a discrete position. Our findings suggest that the molecular machinery and mechanisms for executing Bcl-2-mediated apoptosis as observed in mammals are evolutionary ancient, with early regulation of apoptotic machineries closely resembling their modern counterparts in mammals rather than Caenorhabditis elegans or drosophila.
Publisher: Elsevier BV
Date: 10-2018
DOI: 10.1016/J.JHAZMAT.2018.08.005
Abstract: The sorption of five potent endocrine disruptors as representative hydrophobic organic contaminants (HOCs) namely estrone (E1), 17β-estradiol (E2), estriol (E3), 17α-ethynylestradiol (EE2) and bisphenol A (BPA) on functionalized biochar (fBC) was systematically examined, with a particular focus on the importance of π-electron-donor (phenanthrene: PHEN) and π-electron-acceptors (1,3-dinitrobenzene: DNB, p-amino benzoic acid: PABA) on sorption. Experimental results suggested that hydrogen-bond formation and π-π-electron-donor-acceptor (EDA) interactions were the dominant sorption mechanisms. The sorption of HOCs decreased as E1 > E2 > EE2 > E3 > BPA based on the Freundlich and Polanyi-Mane-models. The comparison of adsorption coefficient (K
Publisher: International Union of Crystallography (IUCr)
Date: 31-03-2010
Publisher: Wiley
Date: 22-02-2019
Publisher: Elsevier BV
Date: 04-2018
Publisher: Springer Science and Business Media LLC
Date: 12-03-2015
Abstract: Subversion of host cell apoptosis is an important survival strategy for viruses to ensure their own proliferation and survival. Certain viruses express proteins homologous in sequence, structure and function to mammalian pro-survival B-cell lymphoma 2 (Bcl-2) proteins, which prevent rapid clearance of infected host cells. In vaccinia virus (VV), the virulence factor F1L was shown to be a potent inhibitor of apoptosis that functions primarily be engaging pro-apoptotic Bim. Variola virus (VAR), the causative agent of smallpox, harbors a homolog of F1L of unknown function. We show that VAR F1L is a potent inhibitor of apoptosis, and unlike all other characterized anti-apoptotic Bcl-2 family members lacks affinity for the Bim Bcl-2 homology 3 (BH3) domain. Instead, VAR F1L engages Bid BH3 as well as Bak and Bax BH3 domains. Unlike its VV homolog, variola F1L only protects against Bax-mediated apoptosis in cellular assays. Crystal structures of variola F1L bound to Bid and Bak BH3 domains reveal that variola F1L forms a domain-swapped Bcl-2 fold, which accommodates Bid and Bak BH3 in the canonical Bcl-2-binding groove, in a manner similar to VV F1L. Despite the observed conservation of structure and sequence, variola F1L inhibits apoptosis using a startlingly different mechanism compared with its VV counterpart. Our results suggest that unlike during VV infection, Bim neutralization may not be required during VAR infection. As molecular determinants for the human-specific tropism of VAR remain essentially unknown, identification of a different mechanism of action and utilization of host factors used by a VAR virulence factor compared with its VV homolog suggest that studying VAR directly may be essential to understand its unique tropism.
Publisher: International Union of Crystallography (IUCr)
Date: 28-07-2015
DOI: 10.1107/S1399004715009402
Abstract: Apoptosis is a key innate defence mechanism to eliminate virally infected cells. To counteract premature host-cell apoptosis, poxviruses have evolved numerous molecular strategies, including the use of Bcl-2 proteins, to ensure their own survival. Here, it is reported that the Deerpox virus inhibitor of apoptosis, DPV022, only engages a highly restricted set of death-inducing Bcl-2 proteins, including Bim, Bax and Bak, with modest affinities. Structural analysis reveals that DPV022 adopts a Bcl-2 fold with a dimeric domain-swapped topology and binds pro-death Bcl-2 proteins via two conserved ligand-binding grooves found on opposite sides of the dimer. Structures of DPV022 bound to Bim, Bak and Bax BH3 domains reveal that a partial obstruction of the binding groove is likely to be responsible for the modest affinities of DPV022 for BH3 domains. These findings reveal that domain-swapped dimeric Bcl-2 folds are not unusual and may be found more widely in viruses. Furthermore, the modest affinities of DPV022 for pro-death Bcl-2 proteins suggest that two distinct classes of anti-apoptotic viral Bcl-2 proteins exist: those that are monomeric and tightly bind a range of death-inducing Bcl-2 proteins, and others such as DPV022 that are dimeric and only bind a very limited number of death-inducing Bcl-2 proteins with modest affinities.
Publisher: MDPI AG
Date: 06-10-2017
DOI: 10.3390/V9100290
Publisher: Elsevier BV
Date: 03-2018
Publisher: American Association for the Advancement of Science (AAAS)
Date: 06-07-2018
Abstract: Human β-defensin 2 permeabilizes and kills fungal cells by specifically targeting the important plasma membrane lipid PIP 2 .
Publisher: Oxford University Press (OUP)
Date: 08-02-2020
DOI: 10.1093/NAR/GKAA076
Abstract: SFPQ is a ubiquitous nuclear RNA-binding protein implicated in many aspects of RNA biogenesis. Importantly, nuclear depletion and cytoplasmic accumulation of SFPQ has been linked to neuropathological conditions such as Alzheimer's disease (AD) and amyotrophic lateral sclerosis (ALS). Here, we describe a molecular mechanism by which SFPQ is mislocalized to the cytoplasm. We report an unexpected discovery of the infinite polymerization of SFPQ that is induced by zinc binding to the protein. The crystal structure of human SFPQ in complex with zinc at 1.94 Å resolution reveals intermolecular interactions between SFPQ molecules that are mediated by zinc. As anticipated from the crystal structure, the application of zinc to primary cortical neurons induced the cytoplasmic accumulation and aggregation of SFPQ. Mutagenesis of the three zinc-coordinating histidine residues resulted in a significant reduction in the zinc-binding affinity of SFPQ in solution and the zinc-induced cytoplasmic aggregation of SFPQ in cultured neurons. Taken together, we propose that dysregulation of zinc availability and/or localization in neuronal cells may represent a mechanism for the imbalance in the nucleocytoplasmic distribution of SFPQ, which is an emerging hallmark of neurodegenerative diseases including AD and ALS.
Publisher: Wiley
Date: 30-12-2014
Abstract: The thiol-disulfide oxidoreductase enzyme DsbA catalyzes the formation of disulfide bonds in the periplasm of Gram-negative bacteria. DsbA substrates include proteins involved in bacterial virulence. In the absence of DsbA, many of these proteins do not fold correctly, which renders the bacteria avirulent. Thus DsbA is a critical mediator of virulence and inhibitors may act as antivirulence agents. Biophysical screening has been employed to identify fragments that bind to DsbA from Escherichia coli. Elaboration of one of these fragments produced compounds that inhibit DsbA activity in vitro. In cell-based assays, the compounds inhibit bacterial motility, but have no effect on growth in liquid culture, which is consistent with selective inhibition of DsbA. Crystal structures of inhibitors bound to DsbA indicate that they bind adjacent to the active site. Together, the data suggest that DsbA may be amenable to the development of novel antibacterial compounds that act by inhibiting bacterial virulence.
Publisher: Wiley
Date: 30-07-2019
DOI: 10.1111/FEBS.15002
Abstract: Scribble is a crucial adaptor protein that plays a pivotal role during establishment and control of cell polarity, impacting many physiological processes ranging from cell migration to immunity and organization of tissue architecture. Scribble harbours a leucine-rich repeat domain and four PDZ domains that mediate most of Scribble's interactions with other proteins. It has become increasingly clear that post-translational modifications substantially impact Scribble-ligand interactions, with phosphorylation being a major modulator of binding to Scribble. To better understand how Scribble PDZ domains direct cell polarity signalling and how phosphorylation impacts this process, we investigated human Scribble interactions with MCC (Mutated in Colorectal Cancer). We systematically evaluated the ability of all four in idual Scribble PDZ domains to bind the PDZ-binding motif (PBM) of MCC as well as MCC phosphorylated at the -1 Ser position. We show that Scribble PDZ1 and PDZ3 are the major interactors with MCC, and that modifications to Ser at the -1 position in the MCC PBM only has a minor effect on binding to Scribble PDZ domains. We then examined the structural basis for these observations by determining the crystal structures of Scribble PDZ1 domain bound to both the unphosphorylated MCC PBM as well as phosphorylated MCC. Our structures indicated that phospho-Ser at the -1 position in MCC is not involved in major contacts with Scribble PDZ1, and in conjunction with our affinity measurements suggest that the impact of phosphorylation at the -1 position of MCC must extend beyond a simple modulation of the affinity for Scribble PDZ domains.
Publisher: Elsevier BV
Date: 06-2017
Publisher: Elsevier BV
Date: 07-2016
Publisher: International Union of Crystallography (IUCr)
Date: 14-11-2012
Publisher: Elsevier BV
Date: 04-2009
DOI: 10.1016/J.STR.2009.02.008
Abstract: UvrA proteins are key actors in DNA damage repair and play an essential role in prokaryotic nucleotide excision repair (NER), a pathway that is unique in its ability to remove a broad spectrum of DNA lesions. Understanding the DNA binding and damage recognition activities of the UvrA family is a critical component for establishing the molecular basis of this process. Here we report the structure of the class II UvrA2 from Deinococcus radiodurans in two crystal forms. These structures, coupled with mutational analyses and comparison with the crystal structure of class I UvrA from Bacillus stearothermophilus, suggest a previously unsuspected role for the identified insertion domains of UvrAs in both DNA binding and damage recognition. Taken together, the available information suggests a model for how UvrA interacts with DNA and thus sheds new light on the molecular mechanisms underlying the role of UvrA in the early steps of NER.
Publisher: Springer Science and Business Media LLC
Date: 20-09-2018
DOI: 10.1038/S41419-018-0992-0
Abstract: Bcl-2 family proteins play a crucial role in regulating apoptosis, a process critical for development, eliminating damaged or infected cells, host-pathogen interactions and in disease. Dysregulation of Bcl-2 proteins elicits an expansive cell survival mechanism promoting cell migration, invasion and metastasis. Through a network of intra-family protein–protein interactions Bcl-2 family members regulate the release of cell death factors from mitochondria. NRZ is a novel zebrafish pro-survival Bcl-2 orthologue resident on mitochondria and the endoplasmic reticulum (ER). However, the mechanism of NRZ apoptosis inhibition has not yet been clarified. Here we examined the interactions of NRZ with pro-apoptotic members of the Bcl-2 family using a combination of isothermal calorimetry and mutational analysis of NRZ. We show that NRZ binds almost all zebrafish pro-apoptotic proteins and displays a broad range of affinities. Furthermore, we define the structural basis for apoptosis inhibition of NRZ by solving the crystal structure of both apo -NRZ and a holo form bound to a peptide spanning the binding motif of the pro-apoptotic zBad, a BH3-only protein orthologous to mammalian Bad. The crystal structure of NRZ revealed that it adopts the conserved Bcl-2 like fold observed for other cellular pro-survival Bcl-2 proteins and employs the canonical ligand binding groove to bind Bad BH3 peptide. NRZ engagement of Bad BH3 involves the canonical ionic interaction between NRZ R86 and Bad D104 and an additional ionic interaction between NRZ D79 and Bad R100, and substitution of either NRZ R86 or D79 to Ala reduces the binding to Bad BH3 tenfold or more. Our findings provide a detailed mechanistic understanding for NRZ mediated anti-apoptotic activity in zebrafish by revealing binding to both Bad and Noxa, suggesting that NRZ is likely to occupy a unique mechanistic role in zebrafish apoptosis regulation by acting as a highly promiscuous pro-apoptotic Bcl-2 binder.
Publisher: International Union of Crystallography (IUCr)
Date: 21-05-2019
DOI: 10.1107/S2053230X19006599
Abstract: Splicing factor proline/glutamine-rich (SFPQ) is an essential RNA-binding protein that is implicated in many aspects of nuclear function. The structures of SFPQ and two paralogs, non-POU domain-containing octamer-binding protein and paraspeckle component 1, from the Drosophila behavior human splicing protein family have previously been characterized. The unusual arrangement of the four domains, two RNA-recognition motifs (RRMs), a conserved region termed the NonA araspeckle (NOPS) domain and a C-terminal coiled coil, in the intertwined dimer provides a potentially unique RNA-binding surface. However, the molecular details of how the four RRMs in the dimeric SFPQ interact with RNA remain to be characterized. Here, a new crystal structure of the dimerization domain of human SFPQ in the C -centered orthorhombic space group C 222 1 with one monomer in the asymmetric unit is presented. Comparison of the new crystal structure with the previously reported structure of SFPQ and analysis of the solution small-angle X-scattering data revealed subtle domain movements in the dimerization domain of SFPQ, supporting the concept of multiple conformations of SFPQ in equilibrium in solution. The domain movement of RRM1, in particular, may reflect the complexity of the RNA substrates of SFPQ. Taken together, the crystal and solution structure analyses provide a molecular basis for further investigation into the plasticity of nucleic acid binding by SFPQ in the absence of the structure in complex with its cognate RNA-binding partners.
Location: United Kingdom of Great Britain and Northern Ireland
Location: Portugal
Location: Portugal
No related grants have been discovered for Sofia Caria.