J. Delon et al., Exclusion of CD43 from the immunological synapse is mediated by phosphorylation-regulated relocation of the cytoskeletal adaptor moesin, IMMUNITY, 15(5), 2001, pp. 691-701
Formation of the immunological synapse requires TOR signal-dependent protei
n redistribution. However, the specific molecular mechanisms controlling pr
otein relocation are not well defined. Moesin is a widely expressed phospho
-protein that links many transmembrane molecules to the cortical actin cyto
skeleton. Here, we demonstrate that TCR-induced exclusion of the large sial
oprotein CD43 from the synapse is an active event mediated by its reversibl
e binding to moesin. Our results also reveal that relocalization of moesin
is associated with changes in the phosphorylation status of this cytoskelet
al adaptor protein. Finally, these findings raise the possibility that the
change in moesin localization resulting from TCR engagement modifies the ov
erall topology of the lymphocyte membrane and facilitates molecular interac
tions at the site of presenting cell contact.