Cell-type-specific rescue of myosin function during Dictyostelium development defines two distinct cell movements required for culmination

Tung Ling L Chen, Wendy A. Wolf, Rex L. Chisholm*

*Corresponding author for this work

Research output: Contribution to journalArticle

22 Scopus citations

Abstract

Mutant Dictyostelium cells lacking any of the component polypeptides of myosin II exhibit developmental defects. To define myosin's role in establishing Dictyostelium's developmental pattern, we have rescued myosin function in a myosin regulatory light chain null mutant (mlcR-) using cell-type-specific promoters. While mlcR- cells fail to progress beyond the mound stage, expression of RLC from the prestalk promoter, ecmA, produces culminants with normal stalks but with defects in spore cell localization. When GFP-marked prestalk and prespore cells expressing ecmA-RLC are mixed with wild-type cells, the mislocalization of prestalk cells, but not prespore cells, is rescued. Time-lapse video recording of ecmA-RLC cells showed that the posterior prespore zone failed to undergo a contraction important for the upward movement of prespore cells. Prespore cells marked with green fluorescent protein (GFP) failed to move toward the tip with the spiral motion typical of wild type. In contrast, expression of RLC in prespore cells using the psA promoter produced balloon-like structures reminiscent of sorocarps but lacking stalks. GFP-labeled prespore cells showed a spiral movement toward the top of the structures. Expression of RLC from the psA promoter restores the normal localization of psA-GFP cells, but not ecmA-GFP cells. These results define two distinct, myosin-dependent movements that are required for establishing a Dictyostelium fruiting body: stalk extension and active movement of the prespore zone that ensures proper placement of the spores atop the stalk. The approach used in these studies provides a direct means of testing the role of cell motility in distinct cell types during a morphogenetic program.

Original languageEnglish (US)
Pages (from-to)3895-3903
Number of pages9
JournalDevelopment
Volume125
Issue number19
StatePublished - Nov 7 1998

Keywords

  • Cell movement
  • Culmination
  • Dictyostelium
  • GFP
  • Green fluorescent protein
  • Myosin

ASJC Scopus subject areas

  • Molecular Biology
  • Developmental Biology

Fingerprint Dive into the research topics of 'Cell-type-specific rescue of myosin function during Dictyostelium development defines two distinct cell movements required for culmination'. Together they form a unique fingerprint.

  • Cite this