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Mechanically induced actin-mediated rocketing of phagosomes.

ABSTRACT: Actin polymerization can be induced in Dictyostelium by compressing the cells to bring phagosomes filled with large particles into contact with the plasma membrane. Asymmetric actin assembly results in rocketing movement of the phagosomes. We show that the compression-induced assembly of actin at the cytoplasmic face of the plasma membrane involves the Arp2/3 complex. We also identify two other proteins associated with the mechanically induced actin assembly. The class I myosin MyoB accumulates at the plasma membrane-phagosome interface early during the initiation of the response, and coronin is recruited as the actin filaments are disassembling. The forces generated by rocketing phagosomes are sufficient to push the entire microtubule apparatus forward and to dislocate the nucleus.

SUBMITTER: Clarke M

PROVIDER: S-EPMC1635377 | biostudies-literature | 2006 Nov

REPOSITORIES: biostudies-literature

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Mechanically induced actin-mediated rocketing of phagosomes.

Clarke Margaret M Müller-Taubenberger Annette A Anderson Kurt I KI Engel Ulrike U Gerisch Günther G

Molecular biology of the cell 20060913 11

Actin polymerization can be induced in Dictyostelium by compressing the cells to bring phagosomes filled with large particles into contact with the plasma membrane. Asymmetric actin assembly results in rocketing movement of the phagosomes. We show that the compression-induced assembly of actin at the cytoplasmic face of the plasma membrane involves the Arp2/3 complex. We also identify two other proteins associated with the mechanically induced actin assembly. The class I myosin MyoB accumulates ...[more]

PMID: 16971511

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