Positive charge modifications alter the ability of XIP to inhibit the plasma membrane calcium pump
- 1 September 1996
- journal article
- research article
- Published by American Physiological Society in American Journal of Physiology-Cell Physiology
- Vol. 271 (3), C736-C741
- https://doi.org/10.1152/ajpcell.1996.271.3.c736
Abstract
Exchange inhibitory peptide (XIP; RRLLFYKYVYKRYRAGKQRG) is the shortest peptide that inhibits the plasma membrane Ca pump at high Ca (A. Enyedi, T. Vorherr, P. James, D. J. McCormick, A. G. Filoteo, E. Carafoli, and J. T. Penniston, J. Biol. Chem. 264: 12313-12321, 1989). Sulfosuccinimidyl acetate (SNA)-modified XIP does not inhibit the Ca pump; SNA neutralizes the positive charge on Lys at positions 7, 11, and 17. Peptide 2CK-XIP (RRLLFYRYVYRCYCAGRQKG) inhibits the pump, but the iodoacetamido-modified peptide does not inhibit. Three peptide analogues, in which 7, 11, and 17 were Ala, Cys, or Lys, inhibited about as well as XIP. SNA modification of these analogues (each with 1 Lys) did not inhibit. SNA modification of 2CK-XIP results in a peptide that does not inhibit; thus position 19 is important. Our results suggest that it is critical that position 19 be positively charged, that positions 7, 11, and 17 are important contact points between XIP and the Ca pump (with at least one positively charged), and that, whereas it is not essential that residues 12 and 14 be positive, they cannot be negative.Keywords
This publication has 9 references indexed in Scilit:
- Use of Cysteine Replacements and Chemical Modification to Alter XIP, the Autoinhibitory Region of the Na‐Ca ExchangerAnnals of the New York Academy of Sciences, 1996
- Modifications of XIP, the Autoinhibitory Region of the Na‐Ca Exchanger, Alter Its Ability to Inhibit the Na‐Ca Exchanger in Bovine Sarcolemmal VesiclesaAnnals of the New York Academy of Sciences, 1996
- Acetylation with succinimidyl acetate affects both the catalytic site and the regulation of the erythrocyte Ca2+ pumpBiochemical Journal, 1994
- The calmodulin‐binding site of the plasma membrane Ca2+ pump interacts with the transduction domain of the enzymeProtein Science, 1992
- The Calcium Pump of the Surface Membrane and of the Sarcoplasmic ReticulumAnnual Review of Physiology, 1989
- [23] Na+,K+-pump stoichiometry and coupling in inside-out vesicles from red blood cell membranesMethods in Enzymology, 1989
- Molecular properties of the red cell calcium pump: I. Effects of calmodulin, proteolytic digestion and drugs on the kinetics of active calcium uptake in inside-out red cell membrane vesiclesCell Calcium, 1980
- Characteristics and regulation of active calcium transport in inside-out red cell membrane vesiclesBiochimica et Biophysica Acta (BBA) - Biomembranes, 1980
- ATPase and phosphatase activities from human red cell membranes: I. The effects of N-ethylmaleimideThe Journal of Membrane Biology, 1977