Allosteric links between the hydrophilic N-terminus and transmembrane core of human Na+/H+ antiporter NHA2
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985823%3A_____%2F22%3A00564736" target="_blank" >RIV/67985823:_____/22:00564736 - isvavai.cz</a>
Result on the web
<a href="https://doi.org/10.1002/pro.4460" target="_blank" >https://doi.org/10.1002/pro.4460</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1002/pro.4460" target="_blank" >10.1002/pro.4460</a>
Alternative languages
Result language
angličtina
Original language name
Allosteric links between the hydrophilic N-terminus and transmembrane core of human Na+/H+ antiporter NHA2
Original language description
The human Na+/H+ antiporter NHA2 (SLC9B2) transports Na+ or Li+ across the plasma membrane in exchange for protons, and is implicated in various pathologies. It is a 537 amino acids protein with an 82 residues long hydrophilic cytoplasmic N-terminus followed by a transmembrane part comprising 14 transmembrane helices. We optimized the functional expression of HsNHA2 in the plasma membrane of a salt-sensitive Saccharomyces cerevisiae strain and characterized in vivo a set of mutated or truncated versions of HsNHA2 in terms of their substrate specificity, transport activity, localization, and protein stability. We identified a highly conserved proline 246, located in the core of the protein, as being crucial for ion selectivity. The replacement of P246 with serine or threonine resulted in antiporters with altered substrate specificity that were not only highly active at acidic pH 4.0 (like the native antiporter), but also at neutral pH. P246T/S versions also exhibited increased resistance to the HsNHA2-specific inhibitor phloretin. We experimentally proved that a putative salt bridge between E215 and R432 is important for antiporter function, but also structural integrity. Truncations of the first 50-70 residues of the N-terminus doubled the transport activity of HsNHA2, while changes in the charge at positions E47, E56, K57, or K58 decreased the antiporter's transport activity. Thus, the hydrophilic N-terminal part of the protein appears to allosterically auto-inhibit cation transport of HsNHA2. Our data also show this in vivo approach to be useful for a rapid screening of SNP's effect on HsNHA2 activity.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10608 - Biochemistry and molecular biology
Result continuities
Project
<a href="/en/project/GA21-08985S" target="_blank" >GA21-08985S: Eukaryotic Na+/H+ antiporters – key elements in their structure determining activity, biogenesis and physiological functions</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Others
Publication year
2022
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Protein Science
ISSN
0961-8368
e-ISSN
1469-896X
Volume of the periodical
31
Issue of the periodical within the volume
12
Country of publishing house
US - UNITED STATES
Number of pages
22
Pages from-to
e4460
UT code for WoS article
000884401200001
EID of the result in the Scopus database
2-s2.0-85143088259