title: Molecular characterization and expression of equine testicular cytochrome P450 aromatase.
abstract: We characterized testicular equine aromatase and its expression. A 2707 bp cDNA was isolated, it encoded a polypeptide of 503 residues with a deduced molecular mass of 57.8 kDa. The sequence features were those of a cytochrome P450 aromatase, with a 78% polypeptide identity with the human counterpart. The gene has a minimal length of 74 kb comprising at least 9 exons and expresses a 2.8 kb mRNA in the testis. Transient cDNA transfections in E293 cells and in vitro translations in a reticulocyte lysate system allowed aromatase protein and activity detections. The activity increased with androstenedione as substrate in a dose-dependent manner. The isolation of testicular aromatase by a new immunoaffinity method demonstrated that the protein could exist either glycosylated or not with a 2 kDa difference. All these results taken together allow new structural studies to progress in the understanding of this cytochrome P450.
authors.affiliation: Laboratory of Biochemistry and Molecular Biology, EA 2608, IBBA, University of Caen, Esplanade de la Paix, 14032 Caen Cedex, France. bioch.bio.mol@ibba.unicaen.fr
authors.forename: Gilles Eric
authors.initials: GE
authors.lastname: Seralini
authors.forename: Alexey
authors.initials: A
authors.lastname: Tomilin
authors.forename: Pierrïck
authors.initials: P
authors.lastname: Auvray
authors.forename: Celine
authors.initials: C
authors.lastname: Nativelle-Serpentini
authors.forename: Pascal
authors.initials: P
authors.lastname: Sourdaine
authors.forename: Safa
authors.initials: S
authors.lastname: Moslemi
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001141:Aromatase / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification; D001483:Base Sequence; D015139:Blotting, Southern; D002460:Cell Line; D002846:Chromatography, Affinity; D003001:Cloning, Molecular; D006736:Horses; D008297:Male; D008969:Molecular Sequence Data; D017433:Protein Structure, Secondary; D012333:RNA, Messenger / Q000032:analysis; D015183:Restriction Mapping; D013737:Testis / Q000201:enzymology*
chemical_list: D012333:RNA, Messenger; D001141:Aromatase