THE MAJORITY OF HUMAN GLUTATHIONE-PEROXIDASE TYPE-5 (GPX5) TRANSCRIPTS ARE INCORRECTLY SPLICED - IMPLICATIONS FOR THE ROLE OF GPX5 IN THE MALE REPRODUCTIVE-TRACT

An epididymis-specific, secretory glutathione peroxidase (GPX5) has be en proposed previously to play a role in protecting mammalian sperm me mbranes from the deleterious effects of lipid peroxidation, which, if not contained, can lead to reduced fertilizing capacity. Here we repor t the cDNA cloning of human GPX5 and show that the majority of transcr ipts contain a 118 nt frame-shifting deletion, arising, most likely, f rom inappropriate excision of exon 3 during processing. Antisera raise d against recombinant human GPX5 cross-reacted with rat and macaque (M acaca fascicularis) epididymal proteins of the size expected for full- length, active GPX5. However, no similar reactivity could be demonstra ted in any of the human samples tested.