title: Evolution of Bcl-2 homology motifs: homology versus homoplasy.
abstract: Bcl-2 family proteins regulate apoptosis in animals. This protein family includes several homologous proteins and a collection of other proteins lacking sequence similarity except for a Bcl-2 homology (BH)3 motif. Thus, membership in the Bcl-2 family requires only one of the four BH motifs. On this basis, a growing number of diverse BH3-only proteins are being reported. Although compelling cell biological and biophysical evidence validates many BH3-only proteins, claims of significant BH3 sequence similarity are often unfounded. Computational and phylogenetic analyses suggest that only some BH3 motifs arose by divergent evolution from a common ancestor (homology), whereas others arose by convergent evolution or random coincidence (homoplasy), challenging current assumptions about which proteins constitute the extended Bcl-2 family.
authors.affiliation: Molecular Biology of the Cell Laboratory, Ecole Normale Supérieure de Lyon, LBMC UMR 5239 CNRS - UCBL - ENS Lyon, 46 Allée d'Italie, 69364 Lyon Cedex 07, France. abdel.aouacheria@ens-lyon.fr
authors.forename: Abdel
authors.initials: A
authors.lastname: Aouacheria
authors.forename: Valentine
authors.initials: V
authors.lastname: Rech de Laval
authors.forename: Christophe
authors.initials: C
authors.lastname: Combet
authors.forename: J Marie
authors.initials: JM
authors.lastname: Hardwick
mesh_terms: D020816:Amino Acid Motifs; D000818:Animals; D017209:Apoptosis; D001665:Binding Sites; D019143:Evolution, Molecular; D006801:Humans; D008969:Molecular Sequence Data; D010802:Phylogeny; D017434:Protein Structure, Tertiary; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000737:chemistry / Q000145:classification / Q000235:genetics*; D017386:Sequence Homology, Amino Acid
chemical_list: D019253:Proto-Oncogene Proteins c-bcl-2