The protein encoded by this gene catalyzes the formation of 5-oxoproline from gamma-glutamyl dipeptides, the penultimate step in glutathione catabolism, and may play a critical role in glutathione homeostasis. The encoded protein may also play a role in cell proliferation, and the expression of this gene is a potential marker for cancer. Pseudogenes of this gene are located on the long arm of chromosome 5 and the short arm of chromosomes 2 and 20. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Dec 2010].
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Gromov, Gromova, Friis, Timmermans-Wielenga, Rank, Simon, Sauter, Moreira: "Proteomic profiling of mammary carcinomas identifies C7orf24, a gamma-glutamyl cyclotransferase, as a potential cancer biomarker." in: Journal of proteome research, Vol. 9, Issue 8, pp. 3941-53, (2010) (PubMed).