title: Enhancing the tolerance of zebrafish (Danio rerio) to heavy metal toxicity by the expression of plant phytochelatin synthase.
abstract: Phytochelatin synthase (PC synthase) catalyzes a biosynthesis of phytochelatins (PCs), which are small molecules and glutathione (GSH)-derived metal-binding peptides that are essential for the detoxification of heavy metal ions in plants, fungi and worms. In order to enhance tolerance to heavy metal cytotoxicity, mRNA coding for PC synthase from Arabidopsis thaliana (AtPCS1) was introduced into the early embryos of zebrafish. As a result, the heterogeneous expression of PC synthase and the synthesis of PCs from GSH in embryos could be detected. The developing embryos expressing PC synthase (PC-embryos) became more tolerant to Cd toxicity (500 microM exposure). PC-embryos had significantly longer apparent lethal times for 50% of the population (LT50) of 8.17+/-1.08 days, although control embryos had apparent LT50 of 5.43+/-0.66 days. These data suggest that PC synthase can function in developmental zebrafish, and that PCs are highly effective in detoxifying Cd toxicity even in the whole body of a vertebrate species.
authors.affiliation: School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Konishi
authors.forename: Sachiko
authors.initials: S
authors.lastname: Matsumoto
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Tsuruwaka
authors.forename: Kentaro
authors.initials: K
authors.lastname: Shiraki
authors.forename: Kazumasa
authors.initials: K
authors.lastname: Hirata
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Tamaru
authors.forename: Masahiro
authors.initials: M
authors.lastname: Takagi
mesh_terms: D019881:Aminoacyltransferases / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D017360:Arabidopsis / Q000201:enzymology*; D002104:Cadmium / Q000633:toxicity*; D004361:Drug Tolerance; D004625:Embryo, Nonmammalian / Q000187:drug effects / Q000378:metabolism; D015870:Gene Expression; D005978:Glutathione / Q000378:metabolism; D007814:Larva / Q000187:drug effects / Q000378:metabolism; D054811:Phytochelatins; D012333:RNA, Messenger / Q000378:metabolism; D015996:Survival Rate; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D015027:Zebrafish / Q000196:embryology / Q000235:genetics / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D014874:Water Pollutants, Chemical; D002104:Cadmium; D054811:Phytochelatins; D019881:Aminoacyltransferases; C093784:glutathione gamma-glutamylcysteinyltransferase; D005978:Glutathione