Abstract

Talin is a 215-kDa cytoskeletal protein implicated in linking actin filaments to the plasma membrane. We show here that chicken gizzard talin is galactosylated by incubation with UDP-[3H]galactose and galactosyl-transferase. The labeled carbohydrate moiety is removed by beta-elimination and comigrates with Gal beta 1-4GlcNAcitol, indicating that talin belongs to a recently discovered class of cytosolic proteins carrying N-acetylglucosamine (GlcNAc) O-linked to serine or threonine (Holt, G. D., and Hart, G. W. (1986) J. Biol. Chem. 261, 8049-8057). Two glycosylated sequences were identified in the tail domain of talin: ANQAIQMAXQNLVDPAXTQ and GILANQLTNDYGQLAQQ, corresponding to amino acids 1470-1488 and 1883-1899, respectively, of the mouse talin amino acid sequence (Rees, D. J. G., Ades, S. E., Singer, S. J., and Hynes, R. O. (1990) Nature 347, 685-689). The putative glycosylation sites are PAXTQ and QLTND. At most 6% of chicken gizzard talin and 3% of porcine stomach talin are galactosylated by galactosyltransferase. Furthermore, human platelet talin is not labeled at all by the procedure, indicating that it may not be glycosylated.

Highlights

  • Talin is a 215-kDa cytoskeletal protein implicated been found recently

  • Labeling of Chicken Gizzard Talin by UDP-PHJGalactose and Galactosyltransferase-In order to demonstrate glycosylation of chicken gizzard talin, the protein was labeled with tritiated UDP-galactose as described under“Experimental Procedures.”

  • This indicates that the accepting sugar is GlcNAc 0-linked to thperotein, a conclusion corroborated by the finding that treatment with endoglycosidase F does not remove the labeled carbohydrate

Read more

Summary

Introduction

Talin is a 215-kDa cytoskeletal protein implicated been found recently. Despite earlier reports 270 kDa (Rees et al, 1990).It occurs in many different tissues fragment of talin was labeled with [3H]galactose according to the and tissueculture cells at sites where actin filaments are method of Holt et al (1987a).

Results
Conclusion
Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call