NPM1

Nucleophosmin (nucleolar phosphoprotein B23, numatrin)
PDB rendering based on 2p1b.
Available structures PDB 2P1B, 2VXD
Identifiers
Symbols	NPM1; B23; MGC104254; NPM
External IDs	OMIM: 164040 MGI: 3647121 HomoloGene: 81697 GeneCards: NPM1 Gene
Gene Ontology Molecular function • transcription coactivator activity • RNA binding • protein binding • Tat protein binding • histone binding • protein homodimerization activity • ribosomal large subunit binding • ribosomal small subunit binding • protein heterodimerization activity • NF-kappaB binding • unfolded protein binding Cellular component • nucleus • nucleoplasm • nucleoplasm • nucleolus • cytoplasm • centrosome • ribonucleoprotein complex • spindle pole centrosome Biological process • DNA repair • nucleosome assembly • nucleosome assembly • intracellular protein transport • nucleocytoplasmic transport • nucleocytoplasmic transport • anti-apoptosis • response to stress • centrosome cycle • signal transduction • cell aging • protein localization • negative regulation of cell proliferation • negative regulation of centrosome duplication • regulation of endodeoxyribonuclease activity • CenH3-containing nucleosome assembly at centromere • ribosome assembly • interspecies interaction between organisms • positive regulation of NF-kappaB transcription factor activity • protein oligomerization • regulation of endoribonuclease activity Sources: Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	4869	18148
Ensembl	ENSG00000181163	ENSMUSG00000057113
UniProt	P06748	n/a
RefSeq (mRNA)	NM_001037738.2	NM_008722.2
RefSeq (protein)	NP_001032827.1	NP_032748.1
Location (UCSC)	Chr 5: 170.81 – 170.84 Mb	Chr 11: 33.05 – 33.06 Mb
PubMed search	[1]	[2]

Nucleophosmin (NPM), also known as nucleolar phosphoprotein B23 or numatrin, is a protein that in humans is encoded by the NPM1 gene.^[1][2]

Function

NPM1 is associated with nucleolar ribonucleoprotein structures and bind single-stranded nucleic acids. It is involved in the biogenesis of ribosomes and may assist small basic proteins in their transport to the nucleolus. Its regulation through SUMOylation (by SENP3 and SENP5) is another facet of the proteins's regulation and cellular functions.

It is located in the nucleolus, but it can be translocated to the nucleoplasm in case of serum starvation or treatment with anticancer drugs. The protein is phosphorylated.

Nucleophosmin has multiple functions:^[3]

1. Histone chaperons
2. Ribosome biogenesis and transport
3. Genomic stability and DNA repair
4. Endoribonuclease activity
5. Centrosome duplication during cell cycle
6. Regulation of ARF-p53 tumor suppressor pathway
7. RNA helix destabilizing activity
8. Inhibition of caspase-activated DNase
9. Prevents apoptosis

Clinical significance

Chromosomal aberrations involving NPM1 were found in patients with non-Hodgkin lymphoma, acute promyelocytic leukemia, myelodysplastic syndrome, and acute myelogenous leukemia.^[4]

It has been found in the cytoplasm in patients with primary acute myelogenous leukemia.

NPM1 roles in tumorigenesis: NPM1 gene is up-regulated, mutated and chromosomally translocated in many tumor types. NPM1 is transferred from nucleolus to nucleoplasm and cytoplasm by anticancer drugs. When expressed at high level, NPM1 could promote tumor growth by inactivation of tumor suppressor p53/ARF pathway; when expressed at low lever, NPM1 could suppress tumor growth by inhibition of centrosome duplication. NPM1 is haploinsufficient in hemizygous mice that are vulnerable to tumor development. NPM1c+ (cytoplasm form) translocation into cytoplasm could serve as AML remission signal. NPM1 forms pentamer that could serve as a potential anticancer drug target.

Interactions

NPM1 has been shown to interact with

• AKT1,^[5]
• BARD1,^[6]
• BRCA1,^[6] and
• nucleolin.^[7]

Nucleophosmin has multiple binding partners:^[3]

1. rRNA
2. HIV Rev and Rex peptide
3. p53 tumor suppressor
4. ARF tumor suppressor
5. MDM2 (mouse double minute 2, ubiquitin ligase)
6. Ribosome protein S9
7. Phosphatidylinositol 3,4,5-triphosphate (PIP3)
8. Exportin-1 (CRM1, chromosome region maintenance)
9. Nucleolin/C23
10. Transcription target of myc oncogene

References

1. ^ Liu QR, Chan PK (March 1993). "Characterization of seven processed pseudogenes of nucleophosmin/B23 in the human genome". DNA Cell Biol. 12 (2): 149–56. doi:10.1089/dna.1993.12.149. PMID 8471164. 
2. ^ Morris SW, Kirstein MN, Valentine MB, Dittmer KG, Shapiro DN, Saltman DL, Look AT (March 1994). "Fusion of a kinase gene, ALK, to a nucleolar protein gene, NPM, in non-Hodgkin's lymphoma". Science 263 (5151): 1281–4. doi:10.1126/science.8122112. PMID 8122112. http://www.sciencemag.org/cgi/pmidlookup?view=long&pmid=8122112. 
3. ^ ^{a b} Lindström MS (2011). "NPM1/B23: A Multifunctional Chaperone in Ribosome Biogenesis and Chromatin Remodeling". Biochem Res Int 2011: 195209. doi:10.1155/2011/195209. PMC 2989734. PMID 21152184. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2989734. 
4. ^ Falini B, Nicoletti I, Bolli N, Martelli MP, Liso A, Gorello P, Mandelli F, Mecucci C, Martelli MF (April 2007). "Translocations and mutations involving the nucleophosmin (NPM1) gene in lymphomas and leukemias". Haematologica 92 (4): 519–32. doi:10.3324/haematol.11007. PMID 17488663. http://www.haematologica.org/cgi/pmidlookup?view=long&pmid=17488663. 
5. ^ Lee SB, Xuan Nguyen TL, Choi JW, Lee KH, Cho SW, Liu Z, Ye K, Bae SS, Ahn JY (October 2008). "Nuclear Akt interacts with B23/NPM and protects it from proteolytic cleavage, enhancing cell survival". Proc. Natl. Acad. Sci. U.S.A. 105 (43): 16584–9. doi:10.1073/pnas.0807668105. PMC 2569968. PMID 18931307. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2569968. 
6. ^ ^{a b} Sato K, Hayami R, Wu W, Nishikawa T, Nishikawa H, Okuda Y, Ogata H, Fukuda M, Ohta T (July 2004). "Nucleophosmin/B23 is a candidate substrate for the BRCA1-BARD1 ubiquitin ligase". J. Biol. Chem. 279 (30): 30919–22. doi:10.1074/jbc.C400169200. PMID 15184379. 
7. ^ Li YP, Busch RK, Valdez BC, Busch H (April 1996). "C23 interacts with B23, a putative nucleolar-localization-signal-binding protein". Eur. J. Biochem. 237 (1): 153–8. doi:10.1111/j.1432-1033.1996.0153n.x. PMID 8620867. 

Further reading

• Yun C, Wang Y, Mukhopadhyay D, et al. (2008). "Nucleolar protein B23/nucleophosmin regulates the vertebrate SUMO pathway through SENP3 and SENP5 proteases.". J Cell Biol. 183 (4): 589–95. doi:10.1083/jcb.200807185. PMC 2582899. PMID 19015314. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2582899. 
• Haindl M, Harasim T, Eick D, et al. (2008). "The nucleolar SUMO-specific protease SENP3 reverses SUMO modification of nucleophosmin and is required for rRNA processing.". EMBO reports. 9 (3): 273–279. doi:10.1038/embor.2008.3. PMC 2267381. PMID 18259216. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2267381. 
• Li L, Li HS, Pauza CD, et al. (2006). "Roles of HIV-1 auxiliary proteins in viral pathogenesis and host-pathogen interactions.". Cell Res. 15 (11-12): 923–34. doi:10.1038/sj.cr.7290370. PMID 16354571. 
• Gjerset RA (2007). "DNA damage, p14ARF, nucleophosmin (NPM/B23), and cancer.". J. Mol. Histol. 37 (5-7): 239–51. doi:10.1007/s10735-006-9040-y. PMID 16855788. 
• Chen W, Rassidakis GZ, Medeiros LJ (2006). "Nucleophosmin gene mutations in acute myeloid leukemia.". Arch. Pathol. Lab. Med. 130 (11): 1687–92. PMID 17076533. 
• Falini B, Nicoletti I, Bolli N, et al. (2007). "Translocations and mutations involving the nucleophosmin (NPM1) gene in lymphomas and leukemias.". Haematologica 92 (4): 519–32. doi:10.3324/haematol.11007. PMID 17488663. 
• Fankhauser C, Izaurralde E, Adachi Y, et al. (1991). "Specific complex of human immunodeficiency virus type 1 rev and nucleolar B23 proteins: dissociation by the Rev response element.". Mol. Cell. Biol. 11 (5): 2567–75. PMC 360026. PMID 2017166. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=360026. 
• Venkatesh LK, Mohammed S, Chinnadurai G (1990). "Functional domains of the HIV-1 rev gene required for trans-regulation and subcellular localization.". Virology 176 (1): 39–47. doi:10.1016/0042-6822(90)90228-J. PMID 2109912. 
• Cochrane AW, Perkins A, Rosen CA (1990). "Identification of sequences important in the nucleolar localization of human immunodeficiency virus Rev: relevance of nucleolar localization to function.". J. Virol. 64 (2): 881–5. PMC 249184. PMID 2404140. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=249184. 
• Chan PK, Chan WY, Yung BY, et al. (1986). "Amino acid sequence of a specific antigenic peptide of protein B23.". J. Biol. Chem. 261 (30): 14335–41. PMID 2429957. 
• Zhang XX, Thomis DC, Samuel CE (1989). "Isolation and characterization of a molecular cDNA clone of a human mRNA from interferon-treated cells encoding nucleolar protein B23, numatrin.". Biochem. Biophys. Res. Commun. 164 (1): 176–84. doi:10.1016/0006-291X(89)91699-9. PMID 2478125. 
• Hale TK, Mansfield BC (1990). "Nucleotide sequence of a cDNA clone representing a third allele of human protein B23.". Nucleic Acids Res. 17 (23): 10112. PMC 335249. PMID 2602120. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=335249. 
• Chan WY, Liu QR, Borjigin J, et al. (1989). "Characterization of the cDNA encoding human nucleophosmin and studies of its role in normal and abnormal growth.". Biochemistry 28 (3): 1033–9. doi:10.1021/bi00429a017. PMID 2713355. 
• Li XZ, McNeilage LJ, Whittingham S (1989). "The nucleotide sequence of a human cDNA encoding the highly conserved nucleolar phosphoprotein B23.". Biochem. Biophys. Res. Commun. 163 (1): 72–8. doi:10.1016/0006-291X(89)92100-1. PMID 2775293. 
• Chan PK, Aldrich M, Cook RG, Busch H (1986). "Amino acid sequence of protein B23 phosphorylation site.". J. Biol. Chem. 261 (4): 1868–72. PMID 3944116. 
• Bocker T, Bittinger A, Wieland W, et al. (1995). "In vitro and ex vivo expression of nucleolar proteins B23 and p120 in benign and malignant epithelial lesions of the prostate.". Mod. Pathol. 8 (3): 226–31. PMID 7542384. 
• Dundr M, Leno GH, Hammarskjöld ML, et al. (1995). "The roles of nucleolar structure and function in the subcellular location of the HIV-1 Rev protein.". J. Cell. Sci. 108 ( Pt 8): 2811–23. PMID 7593322. 
• Miyazaki Y, Takamatsu T, Nosaka T, et al. (1995). "The cytotoxicity of human immunodeficiency virus type 1 Rev: implications for its interaction with the nucleolar protein B23.". Exp. Cell Res. 219 (1): 93–101. doi:10.1006/excr.1995.1209. PMID 7628555. 
• Szebeni A, Herrera JE, Olson MO (1995). "Interaction of nucleolar protein B23 with peptides related to nuclear localization signals.". Biochemistry 34 (25): 8037–42. doi:10.1021/bi00025a009. PMID 7794916. 
• Kato S, Sekine S, Oh SW, et al. (1995). "Construction of a human full-length cDNA bank.". Gene 150 (2): 243–50. doi:10.1016/0378-1119(94)90433-2. PMID 7821789. 
• Marasco WA, Szilvay AM, Kalland KH, et al. (1995). "Spatial association of HIV-1 tat protein and the nucleolar transport protein B23 in stably transfected Jurkat T-cells.". Arch. Virol. 139 (1-2): 133–54. doi:10.1007/BF01309460. PMID 7826206. 
• Valdez BC, Perlaky L, Henning D, et al. (1994). "Identification of the nuclear and nucleolar localization signals of the protein p120. Interaction with translocation protein B23.". J. Biol. Chem. 269 (38): 23776–83. PMID 8089149.