Interactions of actin, myosin, and an actin-binding protein of rabbit pulmonary macrophages. III. Effects of cytochalasin B.
Low concentrations (greater than or equal to 10(-7) M) of cytochalasin B reversibly inhibit the temperature-dependent gelation of actin by an actin-binding protein. The cytochalasin B concentrations which maximally inhibit actin gel formation are 10-fold lower than the concentrations which maximally impair phagocytosis by intact macrophages. Cytochalasin B also prevents the polymerization of monomeric actin in sucrose extracts of macrophages in the absence but not the presence of 0.1 M CKl. 10(-6) M cytochalasin B dissolves macrophage extract gels and gels comprised of purified actin and actin-binding protein by dissociating actin-binding protein from actin filaments. This concentration of cytochalasin B, however, does not depolymerize the actin filatments.
D000199:Actins / Q000378:metabolism*; D000251:Adenosine Triphosphatases / Q000378:metabolism; D003285:Contractile Proteins / Q000378:metabolism*; D003571:Cytochalasin B / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D008264:Macrophages; D009218:Myosins / Q000378:metabolism*
D000199:Actins; D003285:Contractile Proteins; D003571:Cytochalasin B; D000251:Adenosine Triphosphatases; D009218:Myosins