alpha-Actinin interacts specifically with model membranes containing glycerides and fatty acids.
A method was developed to identify specific protein-lipid interactions of complex lipid mixtures and to assess their effect upon the arrangement of such complexes in monolayers at an air-water interface. Its application to striated muscle alpha-actinin revealed that just two lipids selectively interact with alpha-actinin. One molecule of glyceride and one molecule of fatty acid were found to be associated in a constant stoichiometry with one molecule of the alpha-actinin dimer. In the presence of both glycerides and fatty acids unexpectedly rigid monolayer areas formed. This lipid specificity could be confirmed by brief protease digestion of alpha-actinin liposome mixtures followed by peptide analysis; the peptide patterns of alpha-actinin depended on the presence or absence of only these two lipids. Possible implications of these findings are discussed in the context of Z-line formation.
D000185:Actinin / Q000378:metabolism*; D000818:Animals; D001665:Binding Sites; D002474:Cell-Free System; D005227:Fatty Acids / Q000378:metabolism*; D005989:Glycerides / Q000378:metabolism*; D008081:Liposomes / Q000378:metabolism; D008563:Membrane Lipids / Q000378:metabolism*; D008722:Methods; D008854:Microscopy, Electron; D009124:Muscle Proteins / Q000378:metabolism*; D011485:Protein Binding
D005227:Fatty Acids; D005989:Glycerides; D008081:Liposomes; D008563:Membrane Lipids; D009124:Muscle Proteins; D000185:Actinin