A human metallothionein pseudogene containing AG/CT repetitive elements.
A lambda phage recombinant clone, 25 S, which contains a 15.5-kb EcoRI human genomic DNA fragment, has been characterized. Restriction mapping and Southern blot hybridization indicated a 3.0-kb HindIII fragment containing metallothionein (MT)-like sequences. Several interesting features were found upon comparison of this nucleotide sequence with that of other human MT genes: (1) sequences representing the 5' regulatory region, the 5' untranslated region, and the first exon are not contained in the 3.0-kb HindIII fragment; (2) the coding sequence of the second exon (amino acids 10-31 encoding a portion of the beta-domain of the MT protein) has 11 amino acid changes out of a total of 21, whereas, the third exon (amino acids 32-61, representing the complete alpha-domain of the MT protein) has only 4 amino acid substitutions; however, all cysteine residues are conserved; (3) this MT-like gene retains intron sequences and processing signals; (4) Southern blot analysis of human genomic DNA indicated this MT-like gene is located on a 10.5-kb EcoRI genomic DNA fragment; and (5) unusual AG/CT-rich repetitive elements are located within the second intron and upstream of the second exon of this MT-like gene. This gene is not expressed in response to metal induction in two human cell lines, as shown by northern blot analyses. Based on these observations, this MT-like gene represents a unique nonprocessed pseudogene of the human MT multigene family.
Walker
J M
JM
Department of Biological Sciences, University Biochemistry Group, University of Calgary, Alberta, Canada.
Gedamu
L
L
D000595:Amino Acid Sequence; D001483:Base Sequence; D015139:Blotting, Southern; D002460:Cell Line; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D005786:Gene Expression Regulation; D006801:Humans; D008668:Metallothionein / Q000235:genetics*; D008969:Molecular Sequence Data; D011544:Pseudogenes; D012091:Repetitive Sequences, Nucleic Acid; D015183:Restriction Mapping
D004247:DNA; D008668:Metallothionein