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Updated: May 21, 2026
14:16
Analysis of Physiologic E-Selectin-Mediated Leukocyte Rolling on Microvascular Endothelium
Published on: February 11, 2009
Structural insights into calmodulin-regulated L-selectin ectodomain shedding
Jessica L Gifford1, Hiroaki Ishida, Hans J Vogel
1Biochemistry Research Group, Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada.
The Journal of Biological Chemistry
|June 20, 2012
Summary
Calcium-calmodulin binding to L-selectin
Area of Science:
- Molecular biology
- Cellular signaling
- Structural biology
Background:
- L-selectin glycoprotein receptor initiates leukocyte migration.
- Ectodomain shedding of L-selectin is calcium-calmodulin regulated.
Purpose of the Study:
- Determine the molecular mechanism of calcium-calmodulin regulation of L-selectin shedding.
- Elucidate the structure of calcium-calmodulin bound to the L-selectin cytoplasmic tail.
Main Methods:
- Solution structure determination
- Biophysical studies
Main Results:
- The solution structure of calcium-calmodulin bound to the L-selectin cytoplasmic tail and transmembrane domain was determined.
- Calcium and the transmembrane segment are crucial for calmodulin binding.
- Calmodulin binding regulates L-selectin ectodomain shedding in an inside-out manner.
Conclusions:
- Calmodulin acts as a transmembrane signaling partner.
- This interaction provides molecular insight into leukocyte migration regulation.
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