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PubMed · 9264034

Colchicine activates actin polymerization by microtubule depolymerization.

H I Jung·I Shin·Y M Park·K W Kang·K S Ha
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Abstract

Swiss 3T3 fibroblasts were treated with the microtubule-disrupting agent colchicine to study any interaction between microtubule dynamics and actin polymerization. Colchicine increased the amount of filamentous actin (F-actin), in a dose- and time-dependent manner with a significant increase at 1 h by about 130% over control level. Confocal microscopic observation showed that colchicine increased F-actin contents by stress fiber formation without inducing membrane ruffling. Colchicine did not activate phospholipase C and phospholipase D, whereas lysophosphatidic acid did, indicating that colchicine may have a different mechanism of actin polymerization regulation from LPA. A variety of microtubule-disrupting agents stimulated actin polymerization in Swiss 3T3 and Rat-2 fibroblasts as did colchicine, but the microtubule-stabilizing agent taxol inhibited actin polymerization induced by the above microtubule-disrupting agents. In addition, colchicine-induced actin polymerization was blocked by two protein phosphatase inhibitors, okadaic acid and calyculin A. These results suggest that microtubule depolymerization activates stress fiber formation by serine/threonine dephosphorylation in fibroblasts.

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3T3 CellsActinsAnimalsBiopolymersCell LineColchicineEnzyme ActivationEnzyme InhibitorsMarine ToxinsMiceMicrotubulesOkadaic AcidOxazolesPhospholipase DPhosphoprotein PhosphatasesPhosphorylationProtein Kinase CRatsSerineThreonineType C PhospholipasesJournal ArticleResearch Support, Non-U.S. Gov't

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H I Jung, I Shin, Y M Park, K W Kang, K S Ha. 1997-06-30. Colchicine activates actin polymerization by microtubule depolymerization.. https://pubmed.ncbi.nlm.nih.gov/9264034/

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