Repetin (Rptn), a New Member of the “Fused Gene” Subgroup within the S100 Gene Family Encoding a Murine Epidermal Differentiation Protein

• Published in: Genomics (San Diego, Calif.) Vol. 43; no. 3; pp. 339 - 348
• Main Authors: Krieg, Peter, Schuppler, Monika, Koesters, Robert, Mincheva, Antoaneta, Lichter, Peter, Marks, Friedrich
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 01.08.1997; Elsevier
• Subjects: Amino Acid Sequence; Animals; Base Sequence; Biological and medical sciences; Cell Differentiation - genetics; Chromosome Mapping; Cloning, Molecular; DNA Primers; DNA, Complementary - chemistry; DNA, Complementary - genetics; Epidermis - chemistry; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation; Genes - genetics; Genes. Genome; Genomic Library; In Situ Hybridization, Fluorescence; Mice; Molecular and cellular biology; Molecular genetics; Molecular Sequence Data; Multigene Family; Open Reading Frames - genetics; Proteins - genetics; Repetitive Sequences, Nucleic Acid - genetics; RNA, Messenger - biosynthesis; RNA, Messenger - genetics; S100 Proteins - genetics; Sequence Analysis, DNA - methods; Sequence Homology, Amino Acid; Tumor Cells, Cultured; Genetic mapping; Nucleotide sequence; Rodentia; Epidermis; Homology; Gene organization; Chromosome 3; Cell differentiation; Gene expression; Vertebrata; Mammalia; Mouse; Domain structure; Multigene family
• ISSN: 0888-7543; 1089-8646
• DOI: 10.1006/geno.1997.4818

We report the cloning and characterization of a murine epidermal differentiation gene, repetin (Rptn), exhibiting striking similarity to the genes of the intermediate filament-associated proteins profilaggrin and trichohyalin. The repetin gene consists of three exons and two introns. The first exon is short and untranslated. The deduced amino acid sequence distributed between exons II and III contains 1130 amino acids with a calculated molecular mass of 130 kDa and pIof 7.7. The amino terminus exhibits significant homology to the S100 proteins containing two calcium-binding motifs of the EF-hand type. The remainder coding sequence contains a central segment consisting of 49 tandem repeats of a 12-amino-acid sequence rich in glutamines. By fluorescencein situhybridization the repetin gene was localized to chromosome band 3 F1-2. Expression of repetin mRNA is detectable in the stratified internal epithelia of forestomach and tongue and to a lesser degree in normal skin epidermis, where it is restricted to the differentiated suprabasal cell layers. Based on its chromosomal localization, its genomic organization, and its stage-specific expression during late epidermal differentiation, as well as on the structural features of the encoded protein, we conclude that the repetin gene represents a novel member of the “fused gene” subgroup of the S100 gene family encoding multifunctional epidermal matrix proteins.