title: Tyrosine phosphorylation of Crk-associated substrate lymphocyte-type is a critical element in TCR- and beta 1 integrin-induced T lymphocyte migration.
abstract: Crk-associated substrate (Cas) lymphocyte-type (Cas-L) is a 105-kDa cytoplasmic protein consisting of Src homology-3 domain and multiple YXXP motifs (substrate domain). Our previous studies showed that Cas-L is tyrosine-phosphorylated following the ligation of TCR and beta 1 integrins in T lymphocytes. Here we show that Cas-L is involved in T cell motility following the ligation of TCR and beta 1 integrin. Peripheral T lymphocytes showed a marked increase of migration on fibronectin (FN) after the ligation of TCR. In contrast, the migrating Jurkat cells, in which Cas-L was marginally expressed, were less than one-tenth in number on the same condition. Transfection of wild-type Cas-L into Jurkat cells resulted in restoring CD3 plus FN-induced cell migration. Furthermore, following the ligation of beta 1 integrin alone, the Cas-L transfectants significantly migrated better than the vector control. Mutational analysis of Cas-L revealed that the substrate domain is required for both FN- and CD3-induced tyrosine phosphorylation of Cas-L and cell migration caused by FN alone and CD3 plus FN. In contrast, the Src homology-3 domain is required only for the FN-induced tyrosine phosphorylation of Cas-L and cell migration, but not for CD3-induced tyrosine phosphorylation or CD3 plus FN-induced cell migration. These data strongly suggest that Cas-L is a key molecule in T cell migration induced by the ligation of CD3 and beta 1 integrins and that tyrosine phosphorylation of Cas-L is essential for T cell migration.
authors.affiliation: Division of Tumor Immunology, Dana-Farber Cancer Institute, Department of Medicine, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Ohashi
authors.forename: S
authors.initials: S
authors.lastname: Iwata
authors.forename: K
authors.initials: K
authors.lastname: Kamiguchi
authors.forename: C
authors.initials: C
authors.lastname: Morimoto
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D015703:Antigens, CD / Q000276:immunology; D017252:CD3 Complex / Q000502:physiology; D002464:Cell Migration Inhibition; D002465:Cell Movement / Q000276:immunology*; D005353:Fibronectins / Q000378:metabolism; D006801:Humans; D039041:Integrin alpha4beta1; D039482:Integrin alpha5; D019012:Integrin beta1 / Q000502:physiology*; D016023:Integrins / Q000502:physiology; D019169:Jurkat Cells; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics; D011948:Receptors, Antigen, T-Cell / Q000502:physiology*; D017469:Receptors, Fibronectin / Q000502:physiology; D016201:Receptors, Lymphocyte Homing / Q000502:physiology; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism*; D014162:Transfection; D014443:Tyrosine / Q000378:metabolism*
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D017252:CD3 Complex; D005353:Fibronectins; D039041:Integrin alpha4beta1; D039482:Integrin alpha5; D019012:Integrin beta1; D016023:Integrins; C099942:NEDD9 protein, human; D010750:Phosphoproteins; D016271:Proto-Oncogene Proteins c-myc; D011948:Receptors, Antigen, T-Cell; D017469:Receptors, Fibronectin; D016201:Receptors, Lymphocyte Homing; D014443:Tyrosine