Alternative titles; symbols
HGNC Approved Gene Symbol: NEMP1
Cytogenetic location: 12q13.3 Genomic coordinates (GRCh38): 12:57,055,643-57,088,627 (from NCBI)
NEMP1 is an inner nuclear membrane (INM) protein that binds the small GTPase RAN (601179) (Shibano et al., 2015).
Shibano et al. (2015) obtained a full-length cDNA encoding mouse Nemp1. The deduced 437-amino acid mouse Nemp1 protein has an N-terminal signal peptide, 5 transmembrane domains, and 2 evolutionarily conserved sequences, designated A and B, located in the transmembrane domains and C-terminal regions, respectively. A lys/arg-rich sequence is found in frog, but not mouse, Nemp1. Database analysis indicated that region B of human NEMP1 contains numerous serine phosphorylation sites, including 1 that is located in a BAF (BANF1; 603811)-binding site conserved in vertebrate NEMP2 (616497). Confocal microscopy demonstrated that mouse Nemp1 colocalized well with lamins (see 150320) in the nuclear envelope, but less well with Nup153 (603948) in the nuclear pore complex.
Using frog and mouse Nemp1, Shibano et al. (2015) confirmed that region A of Nemp1 was sufficient for nuclear envelope localization. Further analysis suggested that region B of Nemp1 could function as a nuclear localization signal, and yeast 2-hybrid analysis, followed by pull-down and coimmunoprecipitation assays, showed that region B bound to GTP-bound Ran (601179). Nemp1 bound to itself and, to a lesser extent, to INM proteins, such as Man1 (LEMD3; 607844) and emerin (EMD; 300384), through its transmembrane domains. Shibano et al. (2015) concluded that NEMP1 is a RAN-GTP-binding protein that may control nuclear transport of molecules.
Gross (2015) mapped the NEMP1 gene to chromosome 12q13.3 based on an alignment of the NEMP1 sequence (GenBank BC117436) with the genomic sequence (GRCh38).
Gross, M. B. Personal Communication. Baltimore, Md. 8/12/2015.
Shibano, T., Mamada, H., Hakuno, F., Takahashi, S.-I., Taira, M. The inner nuclear membrane protein Nemp1 is a new type of RanGTP-binding protein in eukaryotes. PLoS One 10: e0127271, 2015. Note: Electronic Article. [PubMed: 25946333] [Full Text: https://doi.org/10.1371/journal.pone.0127271]