Structure and dynamics of the Na+/Ca2+ exchanger from Drosophila melanogaster

• Grant number: 13/17883-2
• Support Opportunities: Regular Research Grants
• Duration: February 01, 2014 - January 31, 2016
• Field of knowledge: Biological Sciences - Biophysics - Molecular Biophysics
• Principal Investigator: Roberto Kopke Salinas
• Grantee: Roberto Kopke Salinas
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Na+/Ca2+ exchangers (NCX) use the electrochemical gradient from Na+ to extrude Ca2+ from the cells. Besides transporting Na+ and Ca2+, the exchangers are regulated by these ions. Thus, binding of Ca2+ to the two cytosolic calcium-binding domains (CBD1 and CBD2) activates the NCX. The exchanger of Drosophila melanogaster, CALX, displays an anomalous behavior because it is inhibited by calcium binding to CBD1, and the CALX-CBD2 domain does not bind Ca2+. The goal of this proposal is to study how Ca2+ binding to the CBD1 domain inhibits the activity of CALX. We will use Nuclear Magnetic Resonance (NMR) spectroscopy in solution to study the structure and dynamics of CBD1 and CBD2 of CALX in the absence and presence of Ca2+. At the moment, there is no structural or dynamics information about the transmembrane regions of eukaryotic Na+/Ca2+ exchangers. We will pursue the development of a protocol to produce 15N-labeled NMR samples of recombinant constructs corresponding to two transmembrane domains of CALX plus the XIP and the r-loop regions. We will assess the adequacy of these constructs to NMR structural studies by recording 1H-15N correlation spectra. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

SAYEGH, RAPHAEL S. R.; TAMAKI, FABIO K.; MARANA, SANDRO R.; SALINAS, ROBERTO K.; ARANTES, GUILHERME M.. Conformational flexibility of the complete catalytic domain of Cdc25B phosphatases. PROTEINS-STRUCTURE FUNCTION AND BIOINFORMATICS, v. 84, n. 11, p. 1567-1575, NOV 2016. (14/19439-5, 08/55914-9, 13/17883-2, 14/21900-2, 12/00543-1)

OLIVEIRA, LUCIANA COUTINHO; SOUZA, DIORGE PAULO; OKA, GABRIEL UMAJI; LIMA, FILIPE DA SILVA; OLIVEIRA, RONALDO JUNIO; FAVARO, DENIZE CRISTINA; WIENK, HANS; BOELENS, ROLF; FARAH, CHUCK SHAKER; SALINAS, ROBERTO KOPKE. VirB7 and VirB9 Interactions Are Required for the Assembly and Antibacterial Activity of a Type IV Secretion System. Structure, v. 24, n. 10, p. 1707-1718, OCT 4 2016. (13/17883-2, 11/07777-5)

ABIKO, LAYARA AKEMI; VITALE, PHELIPE M.; FAVARO, DENIZE C.; HAUK, PRICILA; LI, DA-WEI; YUAN, JIAQI; BRUSCHWEILER-LI, LEI; SALINAS, ROBERTO K.; BRUSCHWEILER, RAFAEL. Model for the allosteric regulation of the Na+/Ca2+ exchanger NCX. PROTEINS-STRUCTURE FUNCTION AND BIOINFORMATICS, v. 84, n. 5, p. 580-590, MAY 2016. (13/50355-0, 13/17883-2, 11/07777-5)