NA14 is a novel nuclear autoantigen with a coiled-coil domain.
The serum from a patient with Sjögren's syndrome (RM serum) was used to screen a human testis cDNA expression library. A cDNA of 865 base pairs containing the entire coding sequence for a novel protein was isolated. The 14-kDa predicted protein contains an acidic domain (amino acids 6-80) with a high frequency of heptad repeats characteristic of alpha-helices that form dimeric coiled-coil structures and an alkaline carboxyl-terminal domain (amino acids 81-119). It seems to be widely expressed, but its expression level varies depending on tissues. A protein of apparent molecular mass of 14 kDa was immunoprecipitated from cell lysates by the autoimmune serum, and it was recognized by rabbit antibodies raised to a recombinant bacterial fusion protein generated from the cDNA clone. Conventional and confocal immunofluorescence microscopy on HeLa and 3T3 cells transiently transfected with a tagged form of the protein showed numerous punctate structures scattered throughout the nucleus. This novel protein has been termed NA14 for Nuclear Autoantigen of 14 kDa.
Ramos-Morales
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Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Spain.
Infante
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Fedriani
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C
Bornens
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Rios
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RM
D000595:Amino Acid Sequence; D000818:Animals; D001324:Autoantigens / Q000737:chemistry* / Q000235:genetics; D001483:Base Sequence; D015153:Blotting, Western; D003001:Cloning, Molecular; D015723:Gene Library; D006367:HeLa Cells; D006801:Humans; D007106:Immune Sera; D019169:Jurkat Cells; D051379:Mice; D018613:Microscopy, Confocal; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000737:chemistry* / Q000235:genetics; D011817:Rabbits; D012984:Software; D014018:Tissue Distribution; D014162:Transfection
D001324:Autoantigens; D007106:Immune Sera; C110204:NA14 nuclear autoantigen; D009687:Nuclear Proteins