title: Boo, a novel negative regulator of cell death, interacts with Apaf-1.
abstract: In this report, we describe the cloning and characterization of Boo, a novel anti-apoptotic member of the Bcl-2 family. The expression of Boo was highly restricted to the ovary and epididymis implicating it in the control of ovarian atresia and sperm maturation. Boo contains the conserved BH1 and BH2 domains, but lacks the BH3 motif. Like Bcl-2, Boo possesses a hydrophobic C-terminus and localizes to intracellular membranes. Boo also has an N-terminal region with strong homology to the BH4 domain found to be important for the function of some anti-apoptotic Bcl-2 homologues. Chromosomal localization analysis assigned Boo to murine chromosome 9 at band d9. Boo inhibits apoptosis, homodimerizes or heterodimerizes with some death-promoting and -suppressing Bcl-2 family members. More importantly, Boo interacts with Apaf-1 and forms a multimeric protein complex with Apaf-1 and caspase-9. Bak and Bik, two pro-apoptotic homologues disrupt the association of Boo and Apaf-1. Furthermore, Boo binds to three distinct regions of Apaf-1. These results demonstrate the evolutionarily conserved nature of the mechanisms of apoptosis. Like Ced-9, the mammalian homologues Boo and Bcl-xL interact with the human counterpart of Ced-4, Apaf-1, and thereby regulate apoptosis.
authors.affiliation: Department of Pathology, The University of Michigan Medical School, Ann Arbor, MI 48109, USA.
authors.forename: Q
authors.initials: Q
authors.lastname: Song
authors.forename: Y
authors.initials: Y
authors.lastname: Kuang
authors.forename: V M
authors.initials: VM
authors.lastname: Dixit
authors.forename: C
authors.initials: C
authors.lastname: Vincenz
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D053477:Apoptotic Protease-Activating Factor 1; D053453:Caspase 9; D020169:Caspases / Q000737:chemistry / Q000502:physiology; D002460:Cell Line; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D017124:Conserved Sequence; D019281:Dimerization; D005260:Female; D015870:Gene Expression; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D046911:Macromolecular Substances; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D010053:Ovary / Q000166:cytology / Q000378:metabolism; D011506:Proteins / Q000737:chemistry / Q000502:physiology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D017386:Sequence Homology, Amino Acid; D013094:Spermatozoa / Q000254:growth & development / Q000378:metabolism
chemical_list: C506592:APAF1 protein, human; C506593:Apaf1 protein, mouse; D053477:Apoptotic Protease-Activating Factor 1; C117144:BCL2-like 10 protein; D046911:Macromolecular Substances; D011506:Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; C506433:CASP9 protein, human; C506434:Casp9 protein, mouse; D053453:Caspase 9; D020169:Caspases