In Bovine Heart Na + /Ca 2+  Exchanger Maximal Ca 2+  i  Affinity Requires Simultaneously High pH i  and PtdIns‐4,5‐P2 Binding to the Carrier | Zendy

POSADA VELIA | Zendy; BEAUGÉ LUIS | Zendy; BERBERIÁN GRACIELA | Zendy

Premium

In Bovine Heart Na + /Ca 2+ Exchanger Maximal Ca 2+ i Affinity Requires Simultaneously High pH i and PtdIns‐4,5‐P2 Binding to the Carrier

Author(s) -

POSADA VELIA,

BEAUGÉ LUIS,

BERBERIÁN GRACIELA

Publication year - 2007

Publication title -

annals of the new york academy of sciences

Language(s) - English

Resource type - Journals

SCImago Journal Rank - 1.712

H-Index - 248

eISSN - 1749-6632

pISSN - 0077-8923

DOI - 10.1196/annals.1387.010

Subject(s) - chemistry , intracellular , deprotonation , isotopes of calcium , biophysics , calcium , analytical chemistry (journal) , ion , biochemistry , chromatography , biology , organic chemistry

Na + i ‐dependent Ca 2+ uptake, Na + ‐dependent Ca 2+ release, and PtdIns‐4,5‐P2 binding to Na + /Ca 2+ exchanger (NCX1) as a function of extravesicular (intracellular) [Ca 2+ ] were measured. Alkalinization increases Ca 2+ i affinity and PtdIns‐4,5‐P2 bound to NCX1; these effects are abolished by pretreatment with PtdIns‐PLC and are insensitive to MgATP. Acidification reduces Ca 2+ i affinity. MgATP reverts it only partially despite the fact that the PtdIns‐4,5‐P2 bound to NCX1 reaches the same levels as at pH 7.8. Extravesicular Na + ‐stimulated and Ca 2+ ‐dependent Ca 2+ efflux indicate the Ca 2+ regulatory site is involved. Therefore, to display maximal affinity to Ca 2+ i , PtdIns‐4,5‐P2 binding and deprotonation of NCX1 are simultaneously need.

This content is not available in your region!

Continue researching here.

Having issues? You can contact us here

Accelerating Research