Integrins
are cell adhesion molecules that are also bi-directional signalling
molecules, that is they signal from the out side to the inside of cells,
and vice versa (Calderwwod et al,
2000). Integrins bind a number of
cytoskeletal proteins, some of which are actin-binding proteins (see
table 1), and some integrin types bind actin itself (Kieffer
et al, 1995).
| Integrin-binding Protein |
Function |
References |
| actin |
microfilaments |
Kieffer
et al, 1995;
Calderwood et al, 2000 |
| a-actinin |
Actin
bundling protein |
Pavalko
et al, 1991;
Otey et
al, 1993 |
| Focal
contact Adhesion kinase |
Signalling
kinase |
|
| Paxillin |
|
|
| Plectin |
A
giant actin and intermediate filament binding protein. |
Geerts
et al, 1999 |
| Talin |
An
actin-binding protein, and a component of the focal contact. |
Calderwood et al,
2002 |
| RACK1 |
Connects PKCe
to integrin b chain |
Besson et al, 2002 |
| Table
1 Integrin binding proteins |
References:-
Besson, A., Wilson, T. L. &
Yong, V. W. (2002) The anchoring protein RACK1 links protein kinase Ce
to integrin b
chains. Requirement for adhesion and motility. J.Biol.Chem. 277,
22073-22084.
Calderwood, D. A., Shattil, S. J. &
Ginsberg, M. H. (2000) Integrins and actin filaments: Reciprocal
regulation of cell adhesion and signaling., J.Biol.Chem. 275,
22607-22610.
Calderwood, D. A., Yan, B., de Pereda,
J. M., Alvarez, B. G., Fujioka, Y., Liddington, R. C. & Ginsberg, M.
H. (2002) The phosphotyrosine binding-like domain of talin activates
integrins. J.Biol.Chem. 277, 21749-21758.
Defilippi, P., Venturino, M., Gulino, D.,
Duperray, A., Boquet, P., Fiorentini, C., Volpe, G., Palmieri, M.,
Silengo, L. & Tarone, G. (1997) Dissection of pathways implicated in
integrin-mediated actin cytoskeleton assembly. J.Biol.Chem. 272,
21726-21734.
Geerts, D., Fontao, L., Nievers, M. J.,
Schaapveld, R. Q. J., Purkis, P. E., Wheeler, G. N., Lane, E. B., Leig,
I. M. & Sonnenberg, A. (1999) Binding of integrin a6b4
to plectin prevents plectin association with F-actin but does not
interfere with intermediate filament binding. J.Cell Biol. 147,
417-434.
Jones, S. L., Wang, J., Turck, C. W. &
Brown, E. J. (1998) A role for actin-bundling protein L-plastin in the
regulation of leukocyte integrin function. Proc.Nat.Acad.Sci. USA.
95, 9331-9336.
Kieffer, J. D., Plopper, G., Ingber, D. E.,
Hartwig, J. H. & Kupper, T. S. (1995) Direct binding of F actin to
the cytoplasmic domain of the a2
intergrin chain in vitro. Biochem.Biophys.Res.Comm. 217,
466-474.
Laukaitis, C. M., Webb, D. J., Donais, K. &
Horwitz, A. F. (2001) Differential dynamics of a5
integrin, paxillin, and a-actinin
during formation and disassembly of adhesions in migrating cells., J.
Cell Biol. 153, 1427-1440.
Löfgren, R., Ng-Sikorski, J., Sjölander, A.
& Andersson, T. (1993) b2-integrin engagement triggers actin
polymerization and phosphatidylinositol trisphosphate formation in
non-adherent human neutrophils, J.Cell Biol. 123, 1597-1605.
Lub, M., van Kooyk, Y., van Vliet, S. J. &
Figdor, C. G. (1997) Dual role of the actin cytoskleton in regulating
cell adhesion mediated by the integrin lymphocyte function-associated
molecule-1, Mol.Biol.Cell. 8, 341-351.
Ng-Sikorski, J., Lindén, L., Eierman, D.,
Franzen, L., Molony, L. & Andersson, T. (1996) Engagement of L-selectin
impairs the actin polymerizing capacity of b2-integrins on neutrophils, J.Cell
Sci. 109, 2361-2369.
Obergfell, A., Judd, B. A., del Pozo, M. A.,
Schwartz, M. A., Koretzky, G. A. & Shattil, S. J. (2001) The
molecular adapter SLP-76 relays signals from platelet integrin aIIbb3
to the actin cytoskeleton., J.Biol.Chem. 276, 5916-5923.
Otey, C.
A., Vasquez, G. B., Burridge, K. & Erickson, B. W. (1993) Mapping of
the a-actinin
binding site with the b1
integrin cytoplasmic domain, J. Biol. Chem. 268, 21193-21197.
Pavalko, F. M., Otey, C. A., Simon, K. O. &
Burridge, K. (1991) Alpha-actinin: a direct link between actin and
integrins, Biochem. Soc. Trans. 19, 1065-1069.
Toshima, J., Toshima, J. Y., Amano, T., Yang,
N., Narumiya, S. & Mizuno, K. (2001) Cofilin phospholrylation by
protein kinase testicular protein kinase 1 and its role in
integrin-mediated actin reorganization and focal adhesion formation. Mol.
Biol. of the Cell. 12, 1131-1145.
Toshima, J., Toshima, J. Y. & Mizuno, K.
(2000) Cofilin phosphorylation by protein kinase TESK1 and its role in
integrin-mediated actin remodeling, Molecular Biology of the Cell. 11,
915.
Wang, J., Chen, H. & Brown, E. J. (2001) L-plastin
peptide activation of avb3-mediated
adhesion requires integrin conformational change and actin filament
disassembly., J.Biol.Chem. 276, 14474-14481. |
