Structure of a gene for the human epidermal 67-kDa keratin.

Abstract

The structure and nucleotide sequence are presented of a gene encoding the human epidermal 67-kDa [kilodalton] keratin. Three genomic clones were isolated from a .lambda. Charon 4A human genomic library by hybridization to a specific c[complementary]DNA probe. One clone of 12.3 kilobase pairs was shown by R-loop, DNA sequence and primer-extension analyses to encode an entire gene of about 6.25 kilobase pairs. Of 8 identified introns, 7 are located within the region that encodes the central coiled-coil .alpha.-helical domain of the protein. Except for 1 intron located at the end of the region encoding this domain, these do not delineate apparent structural subdomains. The positions of 5 of the introns exactly coincide with the positions of introns previously reported in the hamster gene for the intermediate filament protein vimentin. Apparently, the human 67-kDa keratin and vimentin genes arose from a common ancestral gene.