Nucleoplasmin Explained

Symbol:	NPM
Nucleoplasmin family
Interpro:	IPR004301

Nucleoplasmin, the first identified molecular chaperone^[1] is a thermostable acidic protein with a pentameric structure. The protein was first isolated from Xenopus species^{[2] [3] [4]}

Functions

The pentameric protein participates in various significant cellular activities like sperm chromatin remodeling, nucleosome assembly, genome stability, ribosome biogenesis, DNA duplication and transcriptional regulation.^{[4] [5]} During the assembly of regular nucleosomal arrays, these nucleoplasmins transfer the DNA to them by binding to the histones. This reaction requires ATP.^{[2] [6] [7] [8]}

Human proteins

Humans express three members of the nucleoplasmin family:

• Nucleophosmin (NPM1)
• Nucleoplasmin 2 (NPM2)
• Nucleoplasmin 3 (NPM3)

Further reading

• Philpott A, Leno GH . Nucleoplasmin remodels sperm chromatin in Xenopus egg extracts . Cell . 69 . 5 . 759–767 . May 1992 . 1591776 . 10.1016/0092-8674(92)90288-n .
• Laskey RA, Mills AD, Philpott A, Leno GH, Dilworth SM, Dingwall C . The role of nucleoplasmin in chromatin assembly and disassembly . Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences . 339 . 1289 . 263–269 . March 1993 . 8098530 . 10.1098/rstb.1993.0024 . 55822 .

Notes and References

1. Dingwall C, Laskey RA . Nucleoplasmin: the archetypal molecular chaperone . Seminars in Cell Biology . 1 . 1 . 11–17 . February 1990 . 1983266 .
2. Rice P, Garduño R, Itoh T, Katagiri C, Ausio J . Nucleoplasmin-mediated decondensation of Mytilus sperm chromatin. Identification and partial characterization of a nucleoplasmin-like protein with sperm-nuclei decondensing activity in Mytilus californianus . Biochemistry . 34 . 23 . 7563–7568 . June 1995 . 7779801 . 10.1021/bi00023a001 .
3. Dingwall C, Sharnick SV, Laskey RA . A polypeptide domain that specifies migration of nucleoplasmin into the nucleus . Cell . 30 . 2 . 449–458 . September 1982 . 6814762 . 10.1016/0092-8674(82)90242-2 .
4. Tejun S, Yaozhou Z . Nucleoplasmin, an Important Nuclear Chaperone . Chinese Journal of Biochemistry and Molecular Biology . 2007 . 23 . 9 . 718–723 .
5. Frehlick LJ, Eirín-López JM, Ausió J . New insights into the nucleophosmin/nucleoplasmin family of nuclear chaperones . BioEssays . 29 . 1 . 49–59 . January 2007 . 17187372 . 10.1002/bies.20512 .
6. Web site: Nucleoplasmin-like core domain superfamily . Superfamily 1.75, HMM Library and Genome Assignment Server.
7. Ramos I, Fernández-Rivero N, Arranz R, Aloria K, Finn R, Arizmendi JM, Ausió J, Valpuesta JM, Muga A, Prado A . 6 . The intrinsically disordered distal face of nucleoplasmin recognizes distinct oligomerization states of histones . Nucleic Acids Research . 42 . 2 . 1311–1325 . January 2014 . 24121686 . 3902905 . 10.1093/nar/gkt899 .
8. Web site: Nucleoplasmin family . InterPro . EMBL-EBI, Wellcome Trust Genome Campus,European Molecular Biology Laboratory.