title: Purification and characterization of an alpha-actinin-like protein from porcine kidney.
abstract: An alpha-actinin-like protein was partially purified from the Triton-insoluble cytoskeleton of porcine kidney by 0.6 M MgCl2 treatment, ammonium sulfate fractionation, DEAE-cellulose chromatography and hydroxyapatite chromatography. Apparent purity of the kidney protein was approximately 90% by quantitative densitometry of Coomassie-stained polyacrylamide gels. The kidney alpha-actinin-like protein is very similar to muscle alpha-actinins by the following criteria: (1) both kidney protein and muscle alpha-actinins bind to F-actin at a similar ratio; (2) both proteins demonstrate no difference in the actomyosin turbidity assay and the ATPase assay for alpha-actinin activity; (3) both native proteins contain a large core of identical molecular weight resistant to trypsin; (4) on two-dimensional gels, both kidney protein and muscle alpha-actinins have similar isoelectric points of 5.9-6.1. However, kidney alpha-actinin-like protein is not identical in every respect with muscle alpha-actinins. Electrophoretic mobility of the kidney protein is slightly greater than that of chicken gizzard alpha-actinin and is identical to that of a component of chicken skeletal muscle alpha-actinin. One-dimensional peptide mappings of the kidney protein and muscle alpha-actinins were significantly different from each other. The interaction between kidney alpha-actinin-like protein and F-actin is sensitive to Ca2+. Similar Ca2+-sensitivity was observed with other non-muscle cell alpha-actinins.
mesh_terms: D000185:Actinin / Q000302:isolation & purification* / Q000378:metabolism; D000199:Actins / Q000378:metabolism; D000205:Actomyosin / Q000378:metabolism; D000251:Adenosine Triphosphatases / Q000378:metabolism; D000818:Animals; D004591:Electrophoresis, Polyacrylamide Gel; D007668:Kidney / Q000032:analysis*; D008970:Molecular Weight; D009124:Muscle Proteins / Q000302:isolation & purification*; D013552:Swine; D014357:Trypsin / Q000378:metabolism
chemical_list: D000199:Actins; D009124:Muscle Proteins; D000185:Actinin; D000205:Actomyosin; D014357:Trypsin; D000251:Adenosine Triphosphatases