Structure of the spectrin-actin binding site of erythrocyte protein 4.1.
The complete primary structure of the functional site of erythrocyte protein 4.1 involved in spectrin-actin associations has been determined. The sequence of this domain, which contains 67 amino acids and has a molecular mass of 8045 daltons, has been obtained by NH2-terminal sequence analysis of an 8-kDa chymotryptic peptide, three endoproteinase lysine C-cleaved peptides and two peptides obtained by Staphylococcus aureus protease V8 cleavage. All peptides including the 8-kDa domain peptide were purified by reverse-phase high performance liquid chromatography. Antibodies against two different synthetic peptides of the 8-kDa domain are able to inhibit the association between protein 4.1, spectrin, and F-actin, corroborating that the 8-kDa domain is responsible for the formation of a ternary complex. A computer search of the 8-kDa sequence with the National Biomedical Research Foundation database did not detect any significant homologies to known sequences. Protein 4.1 is not related to any known proteins and may represent a new protein superfamily.
D000199:Actins / Q000378:metabolism*; D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000906:Antibodies; D001665:Binding Sites; D001798:Blood Proteins / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D003598:Cytoskeletal Proteins; D010450:Endopeptidases / Q000378:metabolism; D006801:Humans; D008565:Membrane Proteins; D008970:Molecular Weight; D009479:Neuropeptides; D012697:Serine Endopeptidases; D013049:Spectrin / Q000378:metabolism*
D000199:Actins; D000596:Amino Acids; D000906:Antibodies; D001798:Blood Proteins; D003598:Cytoskeletal Proteins; D008565:Membrane Proteins; D009479:Neuropeptides; C028841:erythrocyte membrane band 4.1 protein; C120557:erythrocyte membrane protein band 4.1-like 1; D013049:Spectrin; D010450:Endopeptidases; D012697:Serine Endopeptidases; C028344:glutamyl endopeptidase