Molecular Physiology of Sodium-Calcium Exchange

Re: (0740) Functional differences in NCX1 sodium-calcium exchanger splice varints from kidney and brain

Larry Hryshko
lhryshko@sbrc.umanitoba.ca

On Mon Dec 14, Paul J. Bauer wrote
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>Very interesting findings. What do you think is the origin of these regulatory differences you observe? Could it be some a regulatory modification (e.g. phosphorylation) which is possible only in one of the two splice variants?

Hi Paul,

Thanks. We don't really have an answer to your question. Our speculation is that alternative splicing alters the conformational stability of the Na-induced inactive state. We do not think this involves phosphorylation since these data were obtained in excised patches in the absence of phosphorylating agents. However, we have no data to exclude the possibility that differences in basal phosphorylation are involved. Based on the the work of Schulze, Ruknudin, and Lederer (Poster 881), this possibility will be important to investigate.

Tue Dec 15