Metallothionein 1L (MT1L)

MTs bind 7 to 12 heavy metal atoms per molecule of protein. They are ubiquitous in the animal and plant kingdoms and are found in prokaryotes. In mammals, the cysteine residues are absolutely conserved and serve to coordinate heavy metal atoms such as zinc, cadmium, and copper via mercaptide linkages. In human liver, MTs occur in 2 major forms, MT-I and MT-II. In HeLa cells, MT synthesis is induced by either ionized zinc or ionized cadmium and by glucocorticoid hormones. In man, metallothioneins are encoded by at least 10 to 12 genes separated into 2 groups designated MT-I and MT-II. Masters et al. (1994) noted that, unlike MT-I and MT-II, which are expressed in most organs, MT-III expression appears to be restricted to the brain, and MT-IV is only expressed in certain stratified squamous epithelia. West et al. (1990), and others have mapped the locus containing the MT1 gene family to chromosome 16q13.