Phospholipid hydroperoxide glutathione peroxidase: full-length pig blastocyst cDNA sequence and regulation by selenium status.

We have isolated and sequenced an apparent full-length cDNA clone for phospholipid hydroperoxide glutathione peroxidase (Genbank accession number L12743) from a pig blastocyst cDNA library. The sequence encodes a polypeptide of 170 amino acids, including a TGA-encoded selenocysteine at residue 46, with a calculated M(r) of 19,492 Da. Use of this clone in Northern blot analysis of Se-deficient rat liver revealed that phospholipid hydroperoxide glutathione peroxidase mRNA levels were little affected by Se deficiency, whereas classical glutathione peroxidase mRNA levels were decreased by 90% in the same samples. Lastly, liver phospholipid hydroperoxide glutathione peroxidase mRNA levels were not elevated in female rats, in contrast to classical glutathione peroxidase.