Download Conformational changes governing dengue virus capsid protein

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23 Congress of the International Union for Biochemistry and Molecular Biology
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44 Annual Meeting of the Brazilian Society for Biochemistry and Molecular Biology
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Foz do Iguaçu, PR, Brazil, August 24 to 28 , 2015
Conformational changes governing dengue virus capsid protein function and its
inhibition by pep14-23
André F. Faustino1, Gabriela M. Guerra1, Roland G. Huber2, Axel Hollmann1, Marco M.
Domingues1, Glauce M. Barbosa3, Francisco J. Enguita1, Peter J. Bond2, Miguel
Castanho1, Andrea T. Da Poian3, Fabio C.L. Almeida3, Ivo C. Martins1, Nuno C.
Santos1
1. Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa,
Lisbon, Portugal; 2. Bioinformatics Institute (BII), Agency for Science, Technology and
Research (A*STAR), Singapore; 3 – Instituto de Bioquímica Médica, Universidade
Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
Introduction: Dengue virus (DENV) infection affects millions of people and is becoming
a major global disease for which there is no specific available treatment. pep14-23 is a
recently designed peptide, based on a conserved segment of DENV capsid (C) protein.
It inhibits the interaction of DENV C with host intracellular lipid droplets (LDs), crucial for
viral replication, as well as with VLDL [Carvalho et al. (2012) J. Virol. 86:2096; Martins
et al. (2012) Biochem. J. 444:405; Faustino et al. (2014) Nanomedicine 10:247].
Objectives: Here we analyzed pep14-23 structure and ability to bind different
phospholipids, relating the information obtained with the full-length DENV C structure
and biological activity.
Materials and Methods: Bioinformatics approaches were combined with biophysical
methods such as circular dichroism, tensiometry, NMR and zeta potential
measurements [Faustino et al. (2015) ACS Chem. Biol. 10:517].
Results and Discussion: We show that pep14-23 acquires α-helical conformation
upon binding to negatively-charged phospholipid membranes, displaying an asymmetric
charge distribution structural arrangement. Structure prediction for the N-terminal
segment reveals four viable homodimer orientations that alternatively shield or expose
the DENV C hydrophobic pocket. Taken together, these findings suggest a new
biological role for the disordered N-terminal region, which may function as an
autoinhibitory domain mediating DENV C interaction with its biological targets.
Conclusions: The results fit with our current understanding of DENV C and pep14-23
structure and function, paving the way for similar approaches to understanding
disordered proteins and improved peptidomimetics drug development strategies against
DENV and related Flavivirus infections [Faustino et al. (2015) ACS Chem. Biol. 10:517;
Faustino et al. (2015) Sci. Rep., in press].
Acknowledgements: Horizon 2020 – RISE (European Union), FCT-MEC (Portugal),
CNPq and FAPERJ (Brazil).
Keywords: Dengue virus; biophysics; bioinformatics.
Brazilian Society for Biochemistry and
Molecular Biology (SBBq)