title: Evidence for internuclear signaling in drosophila embryogenesis.
abstract: BACKGROUND
  Syncytial nuclei in Drosophila embryos undergo their first 13 divisions nearly synchronously. In the last several cell cycles, these division events travel across the anterior-posterior axis of the syncytial blastoderm in a wave. The phenomenon is well documented but the underlying mechanisms are not yet understood.
  
  
  RESULTS
  We study timing and positional data obtained from in vivo imaging of Drosophila embryos. We determine the statistical properties of the distribution of division times within and across generations with the null hypothesis that timing of division events is an independent random variable for each nucleus. We also compare timing data with a model of Drosophila cell cycle regulation that does not include internuclear signaling, and to a universal model of phase-dependent signaling to determine the probable form of internuclear signaling in the syncytial embryo.
  
  
  CONCLUSIONS
  The statistical variance of division times is lower than one would expect from uncoordinated activity. In fact, the variance decreases between the 10th and 11th divisions, which demonstrates a contribution of internuclear signaling to the observed synchrony and division waves. Our comparison with a coupled oscillator model leads us to conclude that internuclear signaling must be of Response/Signaling type with a positive impulse.
authors.affiliation: Mathematics, Ohio University, Athens, Ohio.
authors.forename: Richard
authors.initials: R
authors.lastname: Buckalew
authors.affiliation: Biological Sciences, Ohio University, Athens, Ohio.
authors.forename: Kara
authors.initials: K
authors.lastname: Finley
authors.affiliation: Biological Sciences, Ohio University, Athens, Ohio.
authors.forename: Soichi
authors.initials: S
authors.lastname: Tanda
authors.affiliation: Mathematics, Ohio University, Athens, Ohio.
authors.forename: Todd
authors.initials: T
authors.lastname: Young
mesh_terms: D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000196:embryology* / Q000201:enzymology* / Q000235:genetics; D047108:Embryonic Development / Q000235:genetics / Q000502:physiology; D008938:Mitosis / Q000235:genetics / Q000502:physiology
chemical_list: D029721:Drosophila Proteins
keywords: Drosophila; division wave; mitosis; synchronization; synchrony