Interaction of calmodulin with L-selectin at the membrane interface: implication on the regulation of L-selectin shedding.

ABSTRACT: The calmodulin (CaM) hypothesis of ectodomain shedding stipulates that CaM, an intracellular Ca²⁺-dependent regulatory protein, associates with the cytoplasmic domain of L-selectin to regulate ectodomain shedding of L-selectin on the other side of the plasma membrane. To understand the underlying molecular mechanism, we have characterized the interactions of CaM with two peptides derived from human L-selectin. The peptide ARR18 corresponds to the entire cytoplasmic domain of L-selectin (residues Ala317-Tyr334 in the mature protein), and CLS corresponds to residues Lys280-Tyr334, which contains the entire transmembrane and cytoplasmic domains of l-selectin. Monitoring the interaction by fluorescence spectroscopy and other biophysical techniques, we found that CaM can bind to ARR18 in aqueou

SUBMITTER: Deng W 

PROVIDER: S-EPMC3143253 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature