Actin critical concentration optimizes at intermediate [cytochalasin B]/[actin] ratios.
Effect of cytochalasin B on actin critical concentration has been assayed using the fluorescence enhancement of pyrene-labeled actin. A peak effect of cytochalasin B on the critical concentration is observed in the presence of either 100 mM K+, or 100 mM K+ plus 2 mM Mg2+. This may result from two competing activities of cytochalasin B, one associated with its capping activity to the barbed end of actin filaments, and the other associated with its lateral binding site(s) along the filaments resulting in a severing activity of cytochalasin B.
Chemistry Department, Syracuse University, NY 13244.
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F
Wang
B J
BJ
Arauz-Lara
B R
BR
Ware
D000199:Actins / Q000302:isolation & purification / Q000378:metabolism*; D000818:Animals; D003571:Cytochalasin B / Q000494:pharmacology*; D007700:Kinetics; D046911:Macromolecular Substances; D008274:Magnesium / Q000494:pharmacology; D009132:Muscles / Q000378:metabolism; D011188:Potassium / Q000494:pharmacology; D011817:Rabbits; D013050:Spectrometry, Fluorescence
D000199:Actins; D046911:Macromolecular Substances; D003571:Cytochalasin B; D008274:Magnesium; D011188:Potassium