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Witch Nails Krt90whnl A spontaneous mouse mutation affecting nail growth and development

ABSTRACT: Numerous single gene mutations identified in humans and mice result in nail deformities with many similarities between the species. A spontaneous, autosomal, recessive mutation called witch nails whnl is described here where the distal nail matrix and nail bed undergo degenerative changes resulting in formation of an abnormal nail plate causing mice to develop long, curved nails. This mutation arose spontaneously in a colony of MRL MpJ-Faslpr J at The Jackson Laboratory. Homozygous mutant mice are recognizable by 8 weeks of age by their long, curved nails. The whnl mutation, mapped on Chromosome 15, is due to a 7-bp insertion identified in the 3 region of exon 9 in the Krt90 gene formerly Riken cDNA 4732456N10Rik, and is predicted to result in a frameshift that changes serine 476 to arginine and subsequently introduces 36 novel amino acids into the protein before a premature stop codon p. Ser476ArgfsTer36. By immunohistochemistry the normal KRT90 protein is expressed in the nail matrix and nail bed in control mice where lesions are located in mutant mice. Immunoreactivity toward equine KRT124, the ortholog of mouse KRT90, is restricted to the nail bed of the hoof and the mouse nail unit. Equine laminitis lesions are similar to those observed in this mutant mouse suggesting that the latter may be a useful model for this horse disease. This first spontaneous mouse mutation affecting the novel Krt90 gene provides new insight into the normal regulation of the molecular pathways of nail development.

INSTRUMENT(S): Q Exactive Plus

ORGANISM(S): Mus Musculus (ncbitaxon:10090)

SUBMITTER: Robert H. Rice

PROVIDER: MSV000089811 | MassIVE | Tue Jul 05 13:48:00 BST 2022

SECONDARY ACCESSION(S): PXD035095

REPOSITORIES: MassIVE

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Witch Nails Krt90whnl A spontaneous mouse mutation affecting nail growth and development

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