title: The genomic repertoire for cell cycle control and DNA metabolism in S. purpuratus.
abstract: A search of the Strongylocentrotus purpuratus genome for genes associated with cell cycle control and DNA metabolism shows that the known repertoire of these genes is conserved in the sea urchin, although with fewer family members represented than in vertebrates, and with some cases of echinoderm-specific gene diversifications. For example, while homologues of the known cyclins are mostly encoded by single genes in S. purpuratus (unlike vertebrates, which have multiple isoforms), there are additional genes encoding novel cyclins of the B and K/L types. Almost all known cyclin-dependent kinases (CDKs) or CDK-like proteins have an orthologue in S. purpuratus; CDK3 is one exception, whereas CDK4 and 6 are represented by a single homologue, referred to as CDK4. While the complexity of the two families of mitotic kinases, Polo and Aurora, is close to that found in the nematode, the diversity of the NIMA-related kinases (NEK proteins) approaches that of vertebrates. Among the nine NEK proteins found in S. purpuratus, eight could be assigned orthologues in vertebrates, whereas the ninth is unique to sea urchins. Most known DNA replication, DNA repair and mitotic checkpoint genes are also present, as are homologues of the pRB (two) and p53 (one) tumor suppressors. Interestingly, the p21/p27 family of CDK inhibitors is represented by one homologue, whereas the INK4 and ARF families of tumor suppressors appear to be absent, suggesting that these evolved only in vertebrates. Our results suggest that, while the cell cycle control mechanisms known from other animals are generally conserved in sea urchin, parts of the machinery have diversified within the echinoderm lineage. The set of genes uncovered in this analysis of the S. purpuratus genome should enhance future research on cell cycle control and developmental regulation in this model.
authors.affiliation: Observatoire Océanologique de Banyuls-Laboratoire Arago, CNRS-UMR7628/UPMC, 66650 Banyuls-sur-Mer, France. Antonio@obs-banyuls.fr
authors.forename: Antonio
authors.initials: A
authors.lastname: Fernandez-Guerra
authors.forename: Antoine
authors.initials: A
authors.lastname: Aze
authors.forename: Julia
authors.initials: J
authors.lastname: Morales
authors.forename: Odile
authors.initials: O
authors.lastname: Mulner-Lorillon
authors.forename: Bertrand
authors.initials: B
authors.lastname: Cosson
authors.forename: Patrick
authors.initials: P
authors.lastname: Cormier
authors.forename: Cynthia
authors.initials: C
authors.lastname: Bradham
authors.forename: Nikki
authors.initials: N
authors.lastname: Adams
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Robertson
authors.forename: William F
authors.initials: WF
authors.lastname: Marzluff
authors.forename: James A
authors.initials: JA
authors.lastname: Coffman
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Genevière
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002453:Cell Cycle / Q000235:genetics*; D017124:Conserved Sequence; D018844:Cyclin-Dependent Kinases / Q000235:genetics; D004247:DNA / Q000235:genetics / Q000378:metabolism*; D016678:Genome; D008969:Molecular Sequence Data; D010802:Phylogeny; D011494:Protein Kinases / Q000235:genetics; D012617:Sea Urchins / Q000145:classification* / Q000166:cytology / Q000235:genetics*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D004247:DNA; D011494:Protein Kinases; D018844:Cyclin-Dependent Kinases