Inducible nuclear translocation of a STAT protein in Dictyostelium prespore cells: implications for morphogenesis and cell-type regulation

Development. 2001 Apr;128(7):1081-8. doi: 10.1242/dev.128.7.1081.

Abstract

Dd-STATa, the Dictyostelium STAT (signal transducer and activator of transcription) protein, is selectively localised in the nuclei of a small subset of prestalk cells located in the slug tip. Injection of cAMP into the extracellular spaces in the rear of the slug induces rapid nuclear translocation of a Dd-GFP:STATa fusion protein in prespore cells surrounding the site of injection. This suggests that cAMP signals that emanate from the tip direct the localised nuclear accumulation of Dd-STATa. It also shows that prespore cells are competent to respond to cAMP, by Dd-STATa activation, and it implies that cAMP signalling is in some way limiting in the rear of the slug. Co-injection of a specific inhibitor of the cAR1 serpentine cAMP receptor almost completely prevents the cAMP-induced nuclear translocation, showing that most or all of the cAMP signal is transduced by cAR1. Dd-GFP:STATa also rapidly translocates into the nuclei of cells adjoining the front and back cut edges when a slug is bisected. Less severe mechanical disturbances, such as pricking the rear of a slug with an unfilled micropipette, also cause a more limited nuclear translocation of Dd-GFP:STATa. We propose that these signalling events form part of a repair mechanism that is activated when the migrating slug suffers mechanical damage.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biological Transport
  • Cell Nucleus / metabolism
  • Cyclic AMP / metabolism
  • Dictyostelium / growth & development
  • Dictyostelium / metabolism
  • Green Fluorescent Proteins
  • Luminescent Proteins / genetics
  • Luminescent Proteins / metabolism
  • Morphogenesis
  • Nuclear Proteins / metabolism*
  • Protozoan Proteins / metabolism*
  • Receptors, Mating Factor
  • Receptors, Peptide / metabolism
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Transcription Factors / metabolism*

Substances

  • Luminescent Proteins
  • Nuclear Proteins
  • Protozoan Proteins
  • Receptors, Mating Factor
  • Receptors, Peptide
  • Recombinant Fusion Proteins
  • Transcription Factors
  • Green Fluorescent Proteins
  • Cyclic AMP