Dynamic distinctions in the Na+/Ca2+ exchanger adopting the inward- and outward-facing conformational states

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388971%3A_____%2F17%3A00477172" target="_blank" >RIV/61388971:_____/17:00477172 - isvavai.cz</a>

Alternative codes found

RIV/00216208:11310/17:10364655

Result on the web

<a href="http://dx.doi.org/10.1074/jbc.M117.787168" target="_blank" >http://dx.doi.org/10.1074/jbc.M117.787168</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1074/jbc.M117.787168" target="_blank" >10.1074/jbc.M117.787168</a>

Result language

angličtina

Original language name

Dynamic distinctions in the Na+/Ca2+ exchanger adopting the inward- and outward-facing conformational states

Original language description

Na+/Ca2+ exchanger (NCX) proteins operate through the alternating access mechanism, where the ion-binding pocket is exposed in succession either to the extracellular or the intracellular face of the membrane. The archaeal NCX_Mj (Methanococcus jannaschiiNCX) system was used to resolve the backbone dynamics in the inward-facing (IF) and outward-facing (OF) states by analyzing purified preparations of apo- and ion-bound forms of NCX_Mj-WT and its mutant, NCX_Mj-5L6-8. First, the exposure of extracellular and cytosolic vestibules to the bulk phase was evaluated as the reactivity of single cysteine mutants to a fluorescent probe, verifying that NCX_Mj-WT and NCX_Mj-5L6-8 preferentially adopt the OF and IF states, respectively. Next, hydrogen-deuterium exchange-mass spectrometry (HDX-MS) was employed to analyze the backbone dynamics profiles in proteins, preferentially adopting the OF (WT) and IF (5L6-8) states either in the presence or absence of ions. Characteristic differences in the backbone dynamics were identified between apo NCX_Mj-WT and NCX_Mj-5L6-8, thereby underscoring specific conformational patterns owned by the OF and IF states. Saturating concentrations of Na+ or Ca2+ specifically modify HDX patterns, revealing that the ion-bound/occluded states are much more stable (rigid) in the OF than in the IF state. Conformational differences observed in the ion-occluded OF and IF states can account for diversifying the ion-release dynamics and apparent affinity (Km) at opposite sides of the membrane, where specific structure-dynamic elements can effectively match the rates of bidirectional ion movements at physiological ion concentrations.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10608 - Biochemistry and molecular biology

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2017

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Journal of Biological Chemistry

ISSN

0021-9258

e-ISSN

—

Volume of the periodical

292

Issue of the periodical within the volume

29

Country of publishing house

US - UNITED STATES

Number of pages

14

Pages from-to

12311-12323

UT code for WoS article

000406053300026

EID of the result in the Scopus database

2-s2.0-85025151225