Alternative titles; symbols
HGNC Approved Gene Symbol: NAIF1
Cytogenetic location: 9q34.11 Genomic coordinates (GRCh38): 9:128,061,233-128,067,320 (from NCBI)
By screening human ORFs for those that induced apoptosis following transfection into cells, followed by PCR of a human liver cDNA library, Lv et al. (2006) cloned C9ORF90, which they called NAIF1. The deduced 327-amino acid protein contains 2 N-terminal nuclear localization signals, a glycine-rich region, and a homeodomain-like region. Northern blot analysis detected multiple NAIF1 transcripts in nearly all tissues examined, consistent with the existence of alternative RNA splicing forms. Immunofluorescence studies of NAIF1 expressed in HeLa and other cell lines localized NAIF1 to the nucleus.
Using MTT and colony formation assays of NAIF1 expressed in HeLa and HEK293 cells, Lv et al. (2006) showed that overexpression of NAIF1 inhibited cell growth and stable colony formation. Overexpression of NAIF1 induced apoptosis characterized by chromatin condensation and margination that began later than BAX (600040)-induced apoptosis, and NAIF1-induced apoptosis was accompanied by a decrease in mitochondrial transmembrane potential, measured by DiOC6(3) staining, and activation of caspase-3 (CASP3; 600636). Using NAIF1 and mutant constructs expressed in HeLa cells, Lv et al. (2006) showed that NAIF1 amino acids 1-70 were required for NAIF1 nuclear localization and induction of apoptosis.
By genomic sequence analysis, Lv et al. (2006) mapped the C9ORF90 gene to chromosome 9q34.11.
Lv, B., Shi, T., Wang, X., Song, Q., Zhang, Y., Shen, Y., Ma, D., Lou, Y. Overexpression of the novel human gene, nuclear apoptosis-inducing factor 1, induces apoptosis. Int. J. Biochem. Cell Biol. 38: 671-683, 2006. [PubMed: 16378748] [Full Text: https://doi.org/10.1016/j.biocel.2005.11.007]