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Platelet activating factor blocks interkinetic nuclear migration in retinal progenitors through an arrest of the cell

Lucianne Fragel-Madeira1, Tamara Meletti, Rafael M Mariante

  • 1Institute of Biophysics, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.

Plos One
|February 8, 2011
PubMed

Insights

Platelet-activating factor (PAF) blocks nuclear migration in retinal progenitor cells by arresting the cell cycle at the S to G2 transition. This reveals a novel checkpoint in developing retinal cells.

Area of Science:

  • Cell Biology
  • Developmental Biology
  • Neuroscience

Background:

  • Nuclear migration is crucial for retinal development and is regulated by proteins like LIS1.
  • Platelet-activating factor (PAF) is a lipid mediator involved in cell proliferation, but its role in cell cycle regulation is unclear.

Purpose of the Study:

  • To investigate the effects of PAF on cell cycle progression and nuclear migration in retinal progenitor cells.
  • To elucidate the molecular mechanisms underlying PAF's influence on interkinetic nuclear migration (IKNM).

Main Methods:

  • Utilized retinal proliferating progenitors to study PAF's effects on IKNM.
  • Assessed cell cycle progression, nuclear migration velocity, and signaling pathways (PAF receptor, Erk, p38, Chk1).
  • Monitored cyclin B1 levels and nucleotide incorporation to rule out cell death and intra-S checkpoints.

Main Results:

  • PAF inhibited IKNM in retinal progenitor cells.
  • The inhibitory effect was dependent on the PAF receptor, Erk, p38, and Chk1 pathways.
  • PAF did not induce cell death or affect nucleotide incorporation, but prevented the G2-phase increase in cyclin B1.

Conclusions:

  • PAF arrests the cell cycle at the S to G2 transition, thereby blocking IKNM in retinal progenitor cells.
  • These findings suggest a novel checkpoint monitoring the S to G2 phase transition in the developing retina.

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