Abstract
The plasma membrane Ca2+ pump is a calmodulin-regulated P-type ATPase that is an essential element in controlling intracellular Ca2+ concentration. Studies on the gene structure of this pump have revealed an alternate splice option that changes the structure of the calmodulin-binding domain. This change in the structure of the enzyme results in a reduced calmodulin affinity. Tests of the enzyme's activity in the presence of a high calmodulin concentration, approximating that found inside living cells, show that this reduced calmodulin affinity causes a reduced apparent affinity of the enzyme for Ca2+. This shift in the Ca2+ activation occurs in a Ca2+ concentration range crucial to cellular function and is probably the physiologically important consequence of the alternate splice.
Original language | English (US) |
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Pages (from-to) | 41-43 |
Number of pages | 3 |
Journal | Journal of Biological Chemistry |
Volume | 269 |
Issue number | 1 |
State | Published - Jan 7 1994 |
ASJC Scopus subject areas
- Biochemistry
- Molecular Biology
- Cell Biology