Abstract:
:To test the hypothesis that periodic signals and chemotaxis direct later morphogenesis in Dictyostelium discoideum, we investigated cell behavior and cell movement in slugs. Trails of neutral red-stained prestalk and anterior-like cells were recorded by high-resolution digital image processing. Neutral red-stained anterior-like cells in the prespore zone of slugs move straight forward in the direction of slug migration and, furthermore, show coherent periodic cell movement. In contrast, cells in the prestalk zone move along completely different trajectories. Prestalk cells move perpendicular to the direction of slug migration; that is, they rotate around the tip. The cell movement data show that the chemotactic signal in the slug propagates as a three-dimensional scroll wave in the prestalk zone and as a planar wave in the prespore zone. The different behavior of prestalk and prespore cells is most likely caused by a difference in the oscillatory properties of the two cell types. We provide evidence that the slug stage of Dictyostelium behaves like an excitable system and that a (twisted) scroll wave organizes slug formation and migration.
journal_name
Proc Natl Acad Sci U S Aauthors
Siegert F,Weijer CJdoi
10.1073/pnas.89.14.6433keywords:
subject
Has Abstractpub_date
1992-07-15 00:00:00pages
6433-7issue
14eissn
0027-8424issn
1091-6490journal_volume
89pub_type
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