title: An actin-depolymerizing protein (destrin) from porcine kidney. Its action on F-actin containing or lacking tropomyosin.
abstract: An Mr 19 000 protein (destrin) that has the ability to rapidly depolymerize F-actin in a stoichiometric manner was purified from porcine kidney by sequential chromatography on DNase I-agarose, hydroxyapatite, and Sephadex G-75. Its actin-depolymerizing activity is reversibly controlled by changes in KCl concentration but is insensitive to Ca2+ concentration. The rate of depolymerization of F-actin by destrin is much faster than that of spontaneous depolymerization induced by dilution and is not markedly decreased by the addition of end-blocking reagents such as cytochalasin B. These results suggest that destrin depolymerizes F-actin by interacting directly with F-actin protomers. Binding of muscle tropomyosin to F-actin slows down the rate of destrin-induced depolymerization of F-actin by about 30-fold. The data suggest that the destrin-induced depolymerization occurs from the ends of F-actin when F-actin is complexed with tropomyosin, but it takes place from the entire length of F-actin in the absence of tropomyosin.
mesh_terms: D051339:Actin Depolymerizing Factors; D000199:Actins / Q000378:metabolism*; D000818:Animals; D051345:Destrin; D005022:Ethyldimethylaminopropyl Carbodiimide / Q000378:metabolism; D007668:Kidney / Q000378:metabolism*; D007700:Kinetics; D008840:Microfilament Proteins; D008970:Molecular Weight; D010446:Peptide Fragments / Q000032:analysis; D011506:Proteins / Q000302:isolation & purification / Q000378:metabolism*; D013552:Swine; D014335:Tropomyosin / Q000378:metabolism*
chemical_list: D051339:Actin Depolymerizing Factors; D000199:Actins; D051345:Destrin; D008840:Microfilament Proteins; D010446:Peptide Fragments; D011506:Proteins; D014335:Tropomyosin; D005022:Ethyldimethylaminopropyl Carbodiimide