The identification and sequence of the actin-binding domain of human red blood cell beta-spectrin. Academic Article uri icon

abstract

  • The junctions of the red blood cell membrane skeleton are formed by interactions between spectrin and actin protofilaments. A spectrin tryptic peptide of 16.5-kDa apparent molecular mass (based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis) which binds to F-actin in cosedimentation experiments has been identified. The peptide has been partially purified by gel filtration, anion-, and cation exchange chromatography. Intact spectrin heterodimer causes half-maximal inhibition of the 16.5-kDa peptide/F-actin interaction at a concentration of 5 microM. Comparison of the two-dimensional iodopeptide maps of the 16.5-kDa peptide with maps of alpha- and beta-spectrin, demonstrate that the peptide is generated from the beta subunit. It shows no significant relationship to the peptide maps of the beta-spectrin domains I-IV. Protein sequencing indicated that this actin-binding domain represents a stretch of amino acids at the N terminus of the beta subunit from alanine 47 probably through lysine 186. The sequence derived molecular weight of this actin-binding domain is 16,290 g/mol. The sequence presented represents the region of greatest homology among the spectrin supergene family (spectrin, dystrophin, alpha-actinin).

published proceedings

  • J Biol Chem

author list (cited authors)

  • Karinch, A. M., Zimmer, W. E., & Goodman, S. R

citation count

  • 109

complete list of authors

  • Karinch, AM||Zimmer, WE||Goodman, SR

publication date

  • July 1990