title: Gene expression throughout a vertebrate's embryogenesis.
abstract: BACKGROUND
  Describing the patterns of gene expression during embryonic development has broadened our understanding of the processes and patterns that define morphogenesis. Yet gene expression patterns have not been described throughout vertebrate embryogenesis. This study presents statistical analyses of gene expression during all 40 developmental stages in the teleost Fundulus heteroclitus using four biological replicates per stage.
  
  
  RESULTS
  Patterns of gene expression for 7,000 genes appear to be important as they recapitulate developmental timing. Among the 45% of genes with significant expression differences between pairs of temporally adjacent stages, significant differences in gene expression vary from as few as five to more than 660. Five adjacent stages have disproportionately more significant changes in gene expression (> 200 genes) relative to other stages: four to eight and eight to sixteen cell stages, onset of circulation, pre and post-hatch, and during complete yolk absorption. The fewest differences among adjacent stages occur during gastrulation. Yet, at stage 16, (pre-mid-gastrulation) the largest number of genes has peak expression. This stage has an over representation of genes in oxidative respiration and protein expression (ribosomes, translational genes and proteases). Unexpectedly, among all ribosomal genes, both strong positive and negative correlations occur. Similar correlated patterns of expression occur among all significant genes.
  
  
  CONCLUSIONS
  These data provide statistical support for the temporal dynamics of developmental gene expression during all stages of vertebrate development.
authors.affiliation: Department of Environmental and Molecular Toxicology, North Carolina State University, Raleigh, 27695-7633, USA.
authors.forename: Goran
authors.initials: G
authors.lastname: Bozinovic
authors.forename: Tim L
authors.initials: TL
authors.lastname: Sit
authors.forename: David E
authors.initials: DE
authors.lastname: Hinton
authors.forename: Marjorie F
authors.initials: MF
authors.lastname: Oleksiak
mesh_terms: D000818:Animals; D016000:Cluster Analysis; D047108:Embryonic Development / Q000235:genetics*; D023781:Fundulidae / Q000196:embryology / Q000235:genetics*; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D015233:Models, Statistical; D020411:Oligonucleotide Array Sequence Analysis; D012270:Ribosomes / Q000235:genetics; D017423:Sequence Analysis, RNA