title: Involvement of the retinoid X receptor in the development of imposex caused by organotins in gastropods.
abstract: Organotin compounds released from antifouling paints, such as tributyltin (TBT) and triphenyltin (TPT), are potent inducers of imposex (a superimposition of male genital tracts, such as penis and vas deferens, on females) in marine gastropods. Little is known about the induction mechanism of gastropod imposex. Here, we show that organotins bind the human retinoid X receptors (hRXRs) with high affinity and that injection of 9-cis retinoic acid (RA), the natural ligand of hRXRs, into females of the rock shell (Thais clavigera) induces the development of imposex. Cloning of the RXR homologue from T. clavigera revealed that the ligand-binding domain of rock shell RXR was very similar to vertebrate RXR and bound to both 9-cis RA and to organotins. These suggest that RXR plays an important role in inducing the development of imposex, namely, the differentiation and growth of male genital tracts in female gastropods.
authors.affiliation: Laboratory of Environmental Biochemistry, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: Jun-Ichi
authors.initials: J
authors.lastname: Nishikawa
authors.forename: Satoru
authors.initials: S
authors.lastname: Mamiya
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Kanayama
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Nishikawa
authors.forename: Fujio
authors.initials: F
authors.lastname: Shiraishi
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Horiguchi
mesh_terms: D000818:Animals; D004305:Dose-Response Relationship, Drug; D005260:Female; D005835:Genitalia / Q000002:abnormalities / Q000187:drug effects*; D006801:Humans; D008024:Ligands; D008297:Male; D008974:Mollusca / Q000378:metabolism; D009947:Organotin Compounds / Q000633:toxicity*; D010413:Penis / Q000033:anatomy & histology / Q000187:drug effects* / Q000254:growth & development; D047488:Retinoid X Receptors / Q000502:physiology*; D014212:Tretinoin / Q000378:metabolism; D014220:Trialkyltin Compounds / Q000633:toxicity; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
chemical_list: D008024:Ligands; D009947:Organotin Compounds; D047488:Retinoid X Receptors; D014220:Trialkyltin Compounds; D014874:Water Pollutants, Chemical; D014212:Tretinoin