cDNA cloning and expression analysis of Eisenia fetida (Annelida: Oligochaeta) phytochelatin synthase under cadmium exposure.
Metallothioneins (MTs) are central to trace metal homeostasis and detoxification throughout biological systems. Prokaryotes, plants, and fungi utilize both gene encoded cysteine-rich polypeptides (classically designated Class I and II MTs) and enzymatically synthesized cysteine-rich peptides (classically designated Class III MTs or phytochelatins). In contrast, although gene encoded MTs are ubiquitous in animal species the identification of a functional phytochelatin synthase in the nematode Caenorhabditis elegans, a representative member of the Ecdysozoa, provided the first evidence for these metal-binding peptides in animals. By exploiting the conservation observed between species we have been able to clone and transcriptionally characterize a phytochelatin synthase from the immune cells of the earthworm Eisenia fetida, the first evidence for its presence in a phylum belonging to the Lophototrochozoa. The complete coding sequence of this enzyme was determined and the phylogenetic relationship to plant, yeast and nematode enzymes elucidated. Temporal- and dose-profiling of the transcriptional regulation of phytochelatin synthase and MT in response to cadmium was performed by using real-time PCR.
Brulle
Franck
F
Laboratoire d'Ecologie Numérique et d'Ecotoxicologie, EA 3570, Université de Lille 1, Cité Scientifique, Bâtiment SN3, 59655 Villeneuve d'Ascq Cedex, France.
Cocquerelle
Claude
C
Wamalah
Atta Nda
AN
Morgan
Andrew John
AJ
Kille
Peter
P
Leprêtre
Alain
A
Vandenbulcke
Franck
F
D000595:Amino Acid Sequence; D019881:Aminoacyltransferases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D001483:Base Sequence; D002104:Cadmium / Q000494:pharmacology*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry*; D005786:Gene Expression Regulation / Q000187:drug effects*; D008668:Metallothionein / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D009835:Oligochaeta / Q000201:enzymology*; D012989:Soil Pollutants / Q000494:pharmacology; D013997:Time Factors
D018076:DNA, Complementary; D012989:Soil Pollutants; D002104:Cadmium; D008668:Metallothionein; D019881:Aminoacyltransferases; C093784:glutathione gamma-glutamylcysteinyltransferase