Type II Keratin sequence

Predicted MW (human K6a): 62.5 kDa
Observed MW (SDS-PAGE, human K6a): 58 kDa
Isoelectric point (human): 7.4 (R. Moll et al., Cell 1982)

Related to K6 isoforms, and to K6hf, in sequence

Distribution: K5 is expressed along with its partner K14 in the progenitor basal layer of complex epithelia.

Gene cloning and nucleotide sequence

Human:      Lersch et al. (Mol. Cell. Biol. 1989) (gene)
                 GenBank Accession Number NM_000424

Mouse:      Sequence not available

Predicted amino acid sequence

Null mutation phenotype

Not available yet.

Involvement in human disease

Inherited mutations in keratin 5 cause epidermolysis bullosa simplex (EBS), a disorder affecting primarily the skin in which the progenitor basal cells of the epidermis rupture in response to trivial mechanical trauma. There are several variants of EBS diseases, with blistering ranging from mild to very severe. In the latter case, internal stratified epithelia (e.g., oral mucosa) can also be involved. Disease severity correlates with the nature of the mutation, in terms of both its location along the polypeptide chain and the actual change insequence.