In Vitro and in Vivo Characterization of Molecular Interactions between Calmodulin, Ezrin/Radixin/Moesin, and L-selectin.
MetadataShow full item record
L-selectin is a cell adhesion molecule that tethers leukocytes to the luminal walls of venules during inflammation and enables them to roll under the force of blood flow. Clustering of L-selectin during rolling is thought to promote outside-in signals that lead to integrin activation and chemokine receptor expression, ultimately contributing to leukocyte arrest. Several studies have underscored the importance of the L-selectin cytoplasmic tail in functionally regulating adhesion and signaling. Interestingly, the L-selectin tail comprises only 17 amino acids, and yet it is thought to bind simultaneously to several proteins. For example, constitutive association of calmodulin (CaM) and ezrin/radixin/moesin (ERM) to L-selectin confers resistance to proteolysis and microvillar positioning, respectively. In this report we found that recombinant purified CaM and ERM bound non-competitively to the same tail of L-selectin. Furthermore, molecular modeling supported the possibility that CaM, L-selectin, and moesin could form a heterotrimeric complex. Finally, using fluorescence lifetime imaging microscopy to measure fluorescence resonance energy transfer, it was shown that CaM, L-selectin, and ERM could interact simultaneously in vivo. Moreover, L-selectin clustering promoted CaM/ERM interaction in cis (i.e. derived from neighboring L-selectin tails). These results highlight a novel intracellular event that occurs as a consequence of L-selectin clustering, which could participate in transducing signals that promote the transition from rolling to arrest.
Version of record
License start date
The Journal of biological chemistry, 2009, 284 (13), pp. 8833 - 8845
Showing items related by title, author, creator and subject.
Mardakheh, FK; Self, A; Marshall, CJDirectional cell migration involves reorientation of the secretory machinery. However, the molecular mechanisms that control this reorientation are not well characterised. Here, we identify a new Rho effector protein, named ...
International Cancer Genome Consortium PedBrain Tumor ProjectPediatric glioblastoma is one of the most common and most deadly brain tumors in childhood. Using an integrative genetic analysis of 53 pediatric glioblastomas and five in vitro model systems, we identified previously ...
Ecdysone-inducible expression of oncogenic Ha-Ras in NIH 3T3 cells leads to transient nuclear localization of activated extracellular signal-regulated kinase regulated by mitogen-activated protein kinase phosphatase-1. Plows, D; Briassouli, P; Owen, C; Zoumpourlis, V; Garrett, MD; Pintzas, A (2002-03)The Ras family of GTP-binding proteins are key transducers of extracellular signals, particularly through the mitogen-activated protein kinase (MAPK) pathway. Constitutively active forms of Ras are found in a variety of ...