title: Evidence for intron length conservation in a set of mammalian genes associated with embryonic development.
abstract: BACKGROUND
  We carried out an analysis of intron length conservation across a diverse group of nineteen mammalian species. Motivated by recent research suggesting a role for time delays associated with intron transcription in gene expression oscillations required for early embryonic patterning, we searched for examples of genes that showed the most extreme conservation of total intron content in mammals.
  
  
  RESULTS
  Gene sets annotated as being involved in pattern specification in the early embryo or containing the homeobox DNA-binding domain, were significantly enriched among genes with highly conserved intron content. We used ancestral sequences reconstructed with probabilistic models that account for insertion and deletion mutations to distinguish insertion and deletion events on lineages leading to human and mouse from their last common ancestor. Using a randomization procedure, we show that genes containing the homeobox domain show less change in intron content than expected, given the number of insertion and deletion events within their introns.
  
  
  CONCLUSIONS
  Our results suggest selection for gene expression precision or the existence of additional development-associated genes for which transcriptional delay is functionally significant.
authors.affiliation: National University of Ireland, Galway, University Road, Galway, Republic of Ireland. cathal.seoighe@nuigalway.ie
authors.forename: Cathal
authors.initials: C
authors.lastname: Seoighe
authors.forename: Paul K
authors.initials: PK
authors.lastname: Korir
mesh_terms: D000818:Animals; D001483:Base Sequence; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics; D017124:Conserved Sequence; D047108:Embryonic Development / Q000235:genetics*; D019143:Evolution, Molecular; D015870:Gene Expression; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D007438:Introns; D051379:Mice; D009154:Mutation; D017384:Sequence Deletion
chemical_list: D051792:Basic Helix-Loop-Helix Proteins