Molecular cloning of the rat metallothionein 1 (MT-1) mRNA sequence

Starting with liver mRNA from cadmium chloride-treated rats, we constructed a cDNA library. A mouse metallothionein 1 (MT-1) cDNA restriction fragment (Durnam et al. 1980) was used as a hybridization probe to isolate from this library a cDNA (p2A10) which is a nearly complete copy of the rat MT-1 mRNA sequence. Southern analysis of rat DNA, using p2A10 as a probe, together with the screening of a rat genomic library, reveal that the rat MT-1 gene belongs to a family of related sequences. The rat MT-1 gene is inducible both by glucocorticoids and by metals.