Sequence and domain structure of talin.
Talin is a high-molecular-weight cytoskeletal protein concentrated at regions of cell-substratum contact and, in lymphocytes, at cell-cell contacts. Integrin receptors are involved in the attachment of adherent cells to extracellular matrices and of lymphocytes to other cells. In these situations, talin codistributes with concentrations of integrins in the cell surface membrane. Furthermore, in vitro binding studies suggest that integrins bind to talin, although with low affinity. Talin also binds with high affinity to vinculin, another cytoskeletal protein concentrated at points of cell adhesion. Finally, talin is a substrate for the Ca2(+)-activated protease, calpain II, which is also concentrated at points of cell-substratum contact. To learn more about the structure of talin and its involvement in transmembrane connections between extracellular adhesions and the cytoskeleton, we have cloned and sequenced murine talin. We describe a model for the structure of talin based on this sequence and other data. Homologies between talin and other proteins define a novel family of submembranous cytoskeleton-associated proteins all apparently involved in connections to the plasma membrane.
Rees
D J
DJ
Center for Cancer Research, Massachusetts Institute of Technology, Cambridge 02139.
Ades
S E
SE
Singer
S J
SJ
Hynes
R O
RO
D000595:Amino Acid Sequence; D000818:Animals; D002154:Calpain / Q000378:metabolism; D002645:Chickens; D003001:Cloning, Molecular; D003598:Cytoskeletal Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004247:DNA / Q000235:genetics; D005455:Fluorescent Antibody Technique; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009479:Neuropeptides; D009693:Nucleic Acid Hybridization; D010446:Peptide Fragments / Q000378:metabolism; D010750:Phosphoproteins / Q000378:metabolism; D011487:Protein Conformation; D012689:Sequence Homology, Nucleic Acid; D016608:Talin; D000099149:Ezrin
D002154:Calpain; D003598:Cytoskeletal Proteins; D004247:DNA; D008565:Membrane Proteins; D009479:Neuropeptides; D010446:Peptide Fragments; D010750:Phosphoproteins; D016608:Talin; D000099149:Ezrin; C028841:erythrocyte membrane band 4.1 protein; C120557:erythrocyte membrane protein band 4.1-like 1