Tumor Necrosis Factor Alpha Induced Protein 3 Interacting Protein 1 (TNIP1)

Using a yeast 2-hybrid screen to identify proteins that interact with the human immunodeficiency virus (HIV)-1 Nef protein, Fukushi et al. (1999) isolated TNIP1, which they designated NAF1, from an activated leukocyte cDNA library. They obtained full-length NAF1 cDNAs by 5-prime and 3-prime RACE. Fukushi et al. (1999) identified 2 alternatively spliced isoforms of NAF1, NAF1-alpha and NAF1-beta, that differ only in their C-terminal amino acids. NAF1-alpha contains 636 amino acids, and NAF1-beta contains 640 amino acids. Both isoforms have 4 coiled-coil domains and a proline-rich C terminus. Northern blot analysis detected a 2.8-kb transcript in all tissues tested, with strong expression in peripheral blood lymphocytes, spleen, and skeletal muscle, and weak expression in brain.