HGNC Approved Gene Symbol: RANBP3
Cytogenetic location: 19p13.3 Genomic coordinates (GRCh38) : 19:5,916,139-5,978,140 (from NCBI)
The RAN GTPase (601179) plays an essential role in the transport of macromolecules between the cytoplasm and the nucleus. The nucleotide-bound state of RAN is regulated by RANGAP1 (602362), a RAN-specific GTPase activating protein, and by RCC1 (CHC1; 179710), a specific guanine nucleotide exchange factor. Using a yeast 2-hybrid screen with RCC1 as bait, Mueller et al. (1998) isolated a partial human lymphocyte cDNA encoding a protein that they designated RANBP3 (RAN-binding protein-3). They used the partial cDNA to screen HeLa cell libraries and recovered additional cDNAs representing alternatively spliced transcripts encoding 562-amino acid RANBP3-a and 499-amino acid RANBP3-b isoforms. The RANBP3 proteins contain FXFG motifs characteristic of a subgroup of nucleoporins, and a C-terminal domain showing similarity to RANBP1 (601180). RANBP3-a has a calculated molecular mass of 60 kD and pI of 4.5. However, the protein has an apparent molecular mass of 100 kD by SDS-PAGE. Immunofluorescence studies showed that RANBP3 is localized diffusely in the nucleus of interphase mammalian cells but is excluded from nucleoli. Northern blot analysis revealed that RANBP3 is expressed ubiquitously as 1.8- and 3-kb mRNAs.
Mueller et al. (1998) found that, in vitro, RANBP3 formed a trimeric RCC1-RAN-RANBP3 complex, although it did not bind RCC1 directly.
By inclusion within a mapped clone (GenBank AC004602), the Joint Genome Institute mapped the RANBP3 gene to 19p13.3 (Rasooly, 1998).
Mueller, L., Cordes, V. C., Bischoff, F. R., Ponstingl, H. Human RanBP3, a group of nuclear RanGTP binding proteins. FEBS Lett. 427: 330-336, 1998. [PubMed: 9637251] [Full Text: https://doi.org/10.1016/s0014-5793(98)00459-1]
Rasooly, R. S. Personal Communication. Baltimore, Md. 11/30/1998.