Mutations in the helix termination motif of mouse type I IRS keratin genes impair the assembly of keratin intermediate filament

Genomics. 2007 Dec;90(6):703-11. doi: 10.1016/j.ygeno.2007.07.013. Epub 2007 Oct 24.


Two classical mouse hair coat mutations, Rex (Re) and Rex wavy coat (Re(wc)), are linked to the type I inner root sheath (IRS) keratin genes of chromosome 11. An N-ethyl-N-nitrosourea-induced mutation, M100573, also maps close to the type I IRS keratin genes. In this study, we demonstrate that Re and M100573 mice bear mutations in the type I IRS gene Krt25; Re(wc) mice bear an additional mutation in the type I IRS gene Krt27. These three mutations are located in the helix termination motif of the 2B alpha-helical rod domain of a type I IRS keratin protein. Immunohistological analysis revealed abnormal foam-like immunoreactivity with an antibody raised to type II IRS keratin K71 in the IRS of Re/+ mice. These results suggest that the helix termination motif is essential for the proper assembly of types I and II IRS keratin protein complexes and the formation of keratin intermediate filaments.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Motifs
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • DNA / genetics
  • Genetic Linkage
  • Hair / metabolism
  • Hair / pathology
  • Hair Follicle / metabolism
  • Hair Follicle / pathology
  • Immunohistochemistry
  • Intermediate Filaments / chemistry
  • Intermediate Filaments / metabolism
  • Keratins, Hair-Specific / biosynthesis
  • Keratins, Hair-Specific / chemistry*
  • Keratins, Hair-Specific / genetics*
  • Mice
  • Mice, Mutant Strains
  • Molecular Sequence Data
  • Mutation*
  • Phenotype
  • Phylogeny
  • Sequence Deletion
  • Sequence Homology, Amino Acid


  • Keratins, Hair-Specific
  • DNA

Associated data

  • GENBANK/AB288231