title: Discovery of candidate KEN-box motifs using cell cycle keyword enrichment combined with native disorder prediction and motif conservation.
abstract: BACKGROUND
  KEN-box-mediated target selection is one of the mechanisms used in the proteasomal destruction of mitotic cell cycle proteins via the APC/C complex. While annotating the Eukaryotic Linear Motif resource (ELM, http://elm.eu.org/), we found that KEN motifs were significantly enriched in human protein entries with cell cycle keywords in the UniProt/Swiss-Prot database-implying that KEN-boxes might be more common than reported.
  
  
  RESULTS
  Matches to short linear motifs in protein database searches are not, per se, significant. KEN-box enrichment with cell cycle Gene Ontology terms suggests that collectively these motifs are functional but does not prove that any given instance is so. Candidates were surveyed for native disorder prediction using GlobPlot and IUPred and for motif conservation in homologues. Among >25 strong new candidates, the most notable are human HIPK2, CHFR, CDC27, Dab2, Upf2, kinesin Eg5, DNA Topoisomerase 1 and yeast Cdc5 and Swi5. A similar number of weaker candidates were present. These proteins have yet to be tested for APC/C targeted destruction, providing potential new avenues of research.
authors.affiliation: Structural and Computational Biology Unit, EMBL, Meyerhofstrasse 1, D-69117, Heidelberg, Germany.
authors.forename: Sushama
authors.initials: S
authors.lastname: Michael
authors.forename: Gilles
authors.initials: G
authors.lastname: Travé
authors.forename: Chenna
authors.initials: C
authors.lastname: Ramu
authors.forename: Claudia
authors.initials: C
authors.lastname: Chica
authors.forename: Toby J
authors.initials: TJ
authors.lastname: Gibson
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D018797:Cell Cycle Proteins / Q000737:chemistry*; D017124:Conserved Sequence; D006801:Humans; D008969:Molecular Sequence Data
chemical_list: D018797:Cell Cycle Proteins