Two novel phospholipid hydroperoxide glutathione peroxidase genes of Paragonimus westermani induced by oxidative stress.
Phospholipid hydroperoxide glutathione peroxidase (PHGPx; GPx4) plays unique roles in the protection of cells against oxidative stress by catalysing reduction of lipid hydroperoxides. We characterized 2 novel GPx genes from a lung fluke, Paragonimus westermani (designated PwGPx1 and PwGPx2). These single copy genes spanned 6559 and 12 371 bp, respectively, and contained each of 5 intervening introns. The PwGPx2 harboured a codon for Sec and a Sec insertion sequence motif. Proteins encoded by the Paragonimus genes demonstrated a primary structure characteristic to the PHGPx family, including preservation of catalytic and glutathione-binding domains and absence of the subunit interaction domain. Expression of PwGPx1 increased gradually as the parasite matured, whereas that of PwGPx2 was temporally regulated. PwGPx2 was expressed at the basal level from the metacercariae to the 3-week-old juveniles; however, the expression was significantly induced in the 7-week-old immature worms and reached a plateau in the 12-week-old adults and eggs. PwGPx1 and PwGPx2 were largely localized in vitellocytes within vitelline glands and eggs. Oxidative stress-inducible paraquat, juglone and H2O2 substantially augmented the PwGPx1 and PwGPx2 expressions in viable worms by 1.5- to 11-fold. Our results strongly suggested that PwGPxs may actively participate in detoxification of oxidative hazards in P. westermani.
Kim
S-H
SH
Department of Molecular Parasitology, Sungkyunkwan University School of Medicine, Suwon, Korea.
Cai
G-B
GB
Bae
Y-A
YA
Lee
E-G
EG
Lee
Y-S
YS
Kong
Y
Y
D000818:Animals; D004790:Enzyme Induction; D015971:Gene Expression Regulation, Enzymologic; D005979:Glutathione Peroxidase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D015801:Helminth Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D009285:Naphthoquinones / Q000378:metabolism; D018384:Oxidative Stress; D048492:Paragonimus westermani / Q000201:enzymology* / Q000254:growth & development / Q000502:physiology*; D010269:Paraquat / Q000378:metabolism; D000080662:Phospholipid Hydroperoxide Glutathione Peroxidase
D015801:Helminth Proteins; D009285:Naphthoquinones; D006861:Hydrogen Peroxide; D000080662:Phospholipid Hydroperoxide Glutathione Peroxidase; D005979:Glutathione Peroxidase; D010269:Paraquat; C005134:juglone