LANCL proteins are mammalian homologs of bacterial LANC enzymes, which catalyze the addition of the thiol of Cys to dehydrated Ser residues during the biosynthesis of lanthipeptides, a class of natural products formed by post-translational modification of precursor peptides. Three genes coding for the LANCL proteins are present in the human genome, with LANCL1, LANCL2 and LANCL3 encoded on chromosomes 24, 75 and X, respectively. LANCL1 and LANCL2 have been shown to be highly expressed in various parts of the brain and testis in human and mice, along with lower expression in most other tissues examined. Since the discovery of LANCL proteins, much effort has focused on understanding their function(s). LANCL2 plays roles in regulating adriamycin sensitivity and abscisic acid signaling, and the protein is also a novel regulator of Akt phosphorylation by binding to and enhancing the kinase activity of mTORC215. LanCL1 appears to have different functions. LanCL1 was identified as a reduced glutathione (GSH)-binding protein in bovine brain and breast cancer cells.[1]