title: Abundant protein domains occur in proportion to proteome size.
abstract: BACKGROUND
  Conserved domains in proteins have crucial roles in protein interactions, DNA binding, enzyme activity and other important cellular processes. It will be of interest to determine the proportions of genes containing such domains in the proteomes of different eukaryotes.
  
  
  RESULTS
  The average proportion of conserved domains in each of five eukaryote genomes was calculated. In pairwise genome comparisons, the ratio of genes containing a given conserved domain in the two genomes on average reflected the ratio of the predicted total gene numbers of the two genomes. These ratios have been verified using a repository of databases and one of its subdivisions of conserved domains.
  
  
  CONCLUSIONS
  Many conserved domains occur as a constant proportion of proteome size across the five sequenced eukaryotic genomes. This raises the possibility that this proportion is maintained because of functional constraints on interacting domains. The universality of the ratio in the five eukaryotic genomes attests to its potential importance.
authors.affiliation: Agencourt Bioscience Corporation, 100 Cummings Center, Suite 107J, Beverly, MA 01915, USA. jamalek@agencourt.com
authors.forename: J A
authors.initials: JA
authors.lastname: Malek
mesh_terms: D000818:Animals; D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics; D029681:Arabidopsis Proteins / Q000235:genetics; D017173:Caenorhabditis elegans / Q000201:enzymology / Q000235:genetics; D029742:Caenorhabditis elegans Proteins / Q000235:genetics; D020134:Catalytic Domain / Q000235:genetics; D017124:Conserved Sequence; D030562:Databases, Protein / Q000706:statistics & numerical data; D029721:Drosophila Proteins / Q000235:genetics; D004331:Drosophila melanogaster / Q000201:enzymology / Q000235:genetics; D006801:Humans; D020543:Proteome / Q000737:chemistry*; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics
chemical_list: D029681:Arabidopsis Proteins; D029742:Caenorhabditis elegans Proteins; D029721:Drosophila Proteins; D020543:Proteome; D029701:Saccharomyces cerevisiae Proteins