Moesin Interacts with the Cytoplasmic Region of Intercellular Adhesion Molecule-3 and Is Redistributed to the Uropod of T Lymphocytes during Cell Polarization

• Published in: The Journal of cell biology 1997-09, Vol.138 (6), p.1409-1423
• Main Authors: Serrador, Juan M., Alonso-Lebrero, José L., del Pozo, Miguel A., Furthmayr, Heinz, Schwartz-Albiez, Reinhard, Calvo, Javier, Lozano, Francisco, Sánchez-Madrid, Francisco
• Format: Article
• Language: English
• Subjects: Antigens, CD; Antigens, Differentiation; B lymphocytes; Blood Proteins - analysis; Blotting, Western; Cell Adhesion - physiology; Cell Adhesion Molecules - analysis; Cell Adhesion Molecules - chemistry; Cell Adhesion Molecules - metabolism; Cell interaction; Cell lines; Cell membranes; Cell Movement - physiology; Cell Polarity - physiology; Cells; Cellular biology; Chemokines; Chemokines - pharmacology; Cytoplasm - chemistry; Cytoplasm - metabolism; Cytoskeletal Proteins; Cèl·lules T; Fluorescent antibody techniques; Humans; Hyaluronan Receptors - analysis; Interacció cel·lular; Intercellular Adhesion Molecule-1 - analysis; Lymphocytes; Membrane Proteins - analysis; Microfilament Proteins; Molecules; Phosphoproteins - analysis; Precipitin Tests; Protein Structure, Tertiary; Proteins - analysis; Proteins - metabolism; Receptors; T lymphocytes; T-Lymphocytes - chemistry; T-Lymphocytes - cytology; T-Lymphocytes - drug effects
• ISSN: 0021-9525; 1540-8140
• DOI: 10.1083/jcb.138.6.1409

During activation, T lymphocytes become motile cells, switching from a spherical to a polarized shape. Chemokines and other chemotactic cytokines induce lymphocyte polarization with the formation of a uropod in the rear pole, where the adhesion receptors intercellular adhesion molecule-1 (ICAM-1), ICAM-3, and CD44 redistribute. We have investigated membrane-cytoskeleton interactions that play a key role in the redistribution of adhesion receptors to the uropod. Immunofluorescence analysis showed that the ERM proteins radixin and moesin localized to the uropod of human T lymphoblasts treated with the chemokine RANTES (regulated on activation, normal T cell expressed, and secreted), a polarization-inducing agent; radixin colocalized with arrays of myosin II at the neck of the uropods, whereas moesin decorated the most distal part of the uropod and colocalized with ICAM-1, ICAM-3, and CD44 molecules. Two other cytoskeletal proteins, β-actin and α-tubulin, clustered at the cell leading edge and uropod, respectively, of polarized lymphocytes. Biochemical analysis showed that moesin coimmunoprecipitates with ICAM-3 in T lymphoblasts stimulated with either RANTES or the polarization-inducing anti-ICAM-3 HP2/19 mAb, as well as in the constitutively polarized T cell line HSB-2. In addition, moesin is associated with CD44, but not with ICAM-1, in polarized T lymphocytes. A correlation between the degree of moesin-ICAM-3 interaction and cell polarization was found as determined by immunofluorescence and immunoprecipitation analysis done in parallel. The moesin-ICAM-3 interaction was specifically mediated by the cytoplasmic domain of ICAM-3 as revealed by precipitation of moesin with a GST fusion protein containing the ICAM-3 cytoplasmic tail from metabolically labeled Jurkat T cell lysates. The interaction of moesin with ICAM-3 was greatly diminished when RANTES-stimulated T lymphoblasts were pretreated with the myosin-disrupting drug butanedione monoxime, which prevents lymphocyte polarization. Altogether, these data indicate that moesin interacts with ICAM-3 and CD44 adhesion molecules in uropods of polarized T cells; these data also suggest that these interactions participate in the formation of links between membrane receptors and the cytoskeleton, thereby regulating morphological changes during cell locomotion.