Marmoset glutathione peroxidases: cDNA sequences, molecular evolution, and gene expression

Area of Science:

• Biochemistry
• Genetics
• Molecular Biology

Background:

• Cellular antioxidant system dysfunction and reactive oxygen species accumulation contribute to diseases like cardiovascular disease, neurodegenerative disorders, tumors, male infertility, and aging.
• Glutathione peroxidases (GPx) are crucial for cellular protection against oxidative damage.
• GPx-1 handles cytosolic hydroperoxides, while GPx-4 uniquely reduces phospholipid hydroperoxides in membranes.

Purpose of the Study:

• To clone and sequence the full-length cDNA for GPx-1 and GPx-4 from the common marmoset (Callithrix jacchus).
• To establish a non-human primate model for studying human diseases associated with oxidative stress.

Main Methods:

• Full-length cDNA for GPx-1 and GPx-4 were cloned and sequenced.
• Gene expression levels were analyzed using quantitative real-time reverse transcriptase-polymerase chain reaction (qRT-PCR).
• Transcription elongation factor-2 was used as a reference gene for normalization.

Main Results:

• The cDNAs encode 202-amino acid GPx-1 and 197-amino acid GPx-4 proteins, both containing selenocysteine and showing high homology (>90%) with mammalian GPxs.
• GPx-1 mRNA expression was highest in the liver, heart, and kidney.
• GPx-4 mRNA expression was most abundant in the testis, followed by the liver, lung, kidney, and spinal cord.

Conclusions:

• The characterized marmoset GPx-1 and GPx-4 provide a valuable non-human primate model.
• These findings support studies investigating the role of glutathione peroxidases in diseases linked to oxidative stress.