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Co-existence of Ras activation in a chemotactic signal transduction pathway and in an autonomous wave - forming system.

ABSTRACT: The activation of Ras is common to two activities in cells of Dictyostelium discoideum: the directed movement in a gradient of chemoattractant and the autonomous generation of propagating waves of actin polymerization on the substrate-attached cell surface. We produced large cells by electric-pulse induced fusion to simultaneously study both activities in one cell. For imaging, a fluorescent label for activated Ras was combined with labels for filamentous actin, PIP3, or PTEN. Chemotactic responses were elicited in a diffusion gradient of cyclic AMP. Waves initiated at sites separate from the front of the cell propagated in all directions. Nevertheless, the wave-forming cells were capable of recognizing the attractant gradient and managed to migrate in its direction.

SUBMITTER: Ecke M

PROVIDER: S-EPMC6343538 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Co-existence of Ras activation in a chemotactic signal transduction pathway and in an autonomous wave - forming system.

Ecke Mary M Gerisch Günther G

Small GTPases 20170131 1

The activation of Ras is common to two activities in cells of <i>Dictyostelium discoideum</i>: the directed movement in a gradient of chemoattractant and the autonomous generation of propagating waves of actin polymerization on the substrate-attached cell surface. We produced large cells by electric-pulse induced fusion to simultaneously study both activities in one cell. For imaging, a fluorescent label for activated Ras was combined with labels for filamentous actin, PIP3, or PTEN. Chemotactic ...[more]

PMID: 28136018

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