Cloning, expression and nuclear localization of human NPM3, a member of the nucleophosmin/nucleoplasmin family of nuclear chaperones

Shackleford, Gregory M.; Ganguly, Amit; MacArthur, Craig A.
January 2001
BMC Genomics;2001, Vol. 2, p1
Academic Journal
Background: Studies suggest that the related proteins nucleoplasmin and nucleophosmin (also called B23, NO38 or numatrin) are nuclear chaperones that mediate the assembly of nucleosomes and ribosomes, respectively, and that these activities are accomplished through the binding of basic proteins via their acidic domains. Recently discovered and less well characterized members of this family of acidic phosphoproteins include mouse nucleophosmin/nucleoplasmin 3 (Npm3) and Xenopus NO29. Here we report the cloning and initial characterization of the human ortholog of Npm3. Results: Human genomic and cDNA clones of NPM3 were isolated and sequenced. NPM3 lies 5.5 kb upstream of FGF8 and thus maps to chromosome 10q24-26. In addition to amino acid similarities, NPM3 shares many physical characteristics with the nucleophosmin/nucleoplasmin family, including an acidic domain, multiple potential phosphorylation sites and a putative nuclear localization signal. Comparative analyses of 14 members of this family from various metazoans suggest that Xenopus NO29 is a candidate ortholog of human and mouse NPM3, and they further group both proteins closer with the nucleoplasmins than with the nucleophosmins. Northern blot analysis revealed that NPM3 was strongly expressed in all 16 human tissues examined, with especially robust expression in pancreas and testis; lung displayed the lowest level of expression. An analysis of subcellular fractions of NIH3T3 cells expressing epitope-tagged NPM3 revealed that NPM3 protein was localized solely in the nucleus. Conclusions: Human NPM3 is an abundant and widely expressed protein with primarily nuclear localization. These biological activities, together with its physical relationship to the chaparones nucleoplasmin and nucleophosmin, are consistent with the proposed function of NPM3 as a molecular chaperone functioning in the nucleus.


Related Articles

  • A subset of the diverse COG0523 family of putative metal chaperones is linked to zinc homeostasis in all kingdoms of life. Haas, Crysten E.; Rodionov, Dmitry A.; Kropat, Janette; Malasarn, Davin; Merchant, Sabeeha S.; de Crécy-Lagard, Valérie // BMC Genomics;2009, Vol. 10, p470 

    Background: COG0523 proteins are, like the nickel chaperones of the UreG family, part of the G3E family of GTPases linking them to metallocenter biosynthesis. Even though the first COG0523-encoding gene, cobW, was identified almost 20 years ago, little is known concerning the function of other...

  • A Proteomic Study on Molecular Mechanism of Poor Grain-Filling of Rice (Oryza sativa L.) Inferior Spikelets. Zhang, Zhixing; Zhao, Hong; Tang, Jun; Li, Zhong; Li, Zhou; Chen, Dongmei; Lin, Wenxiong // PLoS ONE;Feb2014, Vol. 9 Issue 2, p1 

    Cultivars of rice (Oryza sativa L.), especially of the type with large spikelets, often fail to reach the yield potential as expected due to the poor grain-filling on the later flowering inferior spikelets (in contrast to the earlier-flowering superior spikelets). The present study showed that...

  • Cloning, Expression and Crystallisation of SGT1 Cochaperone Protein from Glaciozyma antarctica. Yusof, Nur Athirah; Abu Bakar, Farah Diba; Beddoe, Travis; Abdul Murad, Abdul Munir // AIP Conference Proceedings;Dec2013, Vol. 1571 Issue 1, p292 

    Studies on psycrophiles are now in the limelight of today's post genomic era as they fascinate the research and development industries. The discovery from Glaciozyma antarctica, an extreme cold adapted yeast from Antarctica shows promising future to provide cost effective natural sustainable...

  • The J-protein family: modulating protein assembly, disassembly and translocation. Walsh, Peter; Bursac, Dejan; Yin Chern Law; Cyr, Douglas; Lithgow, Trevor // EMBO Reports;Jun2004, Vol. 5 Issue 6, p567 

    DnaJ is a molecular chaperone and the prototypical member of the J-protein family. J proteins are defined by the presence of a J domain that can regulate the activity of 70-kDa heat-shock proteins. Sequence analysis on the genome of Saccharomyces cerevisiae has revealed 22 proteins that...

  • Functional analysis of the plastid and nuclear encoded CbbX proteins of Cyanidioschyzon merolae. Fujita, Kiyohito; Tanaka, Kan; Sadaie, Yoshito; Ohta, Niji // Genes & Genetic Systems;2008, Vol. 83 Issue 2, p135 

    CbbX is believed to be a transcriptional regulator of the subunit genes (rbcL and rbcS) of RuBisCO (Ribulose 1,5-bisphosphate carboxylase/oxygenase) as well as possibly a molecular chaperon of RuBisCO subunit assembly. The unicellular red alga Cyanidioschyzon merolae strain 10D possesses two...

  • Comparative genomics and evolution of the HSP90 family of genes across all kingdoms of organisms. Chen, Bin; Zhong, Daibin; Monteiro, Antonia // BMC Genomics;2006, Vol. 7, p156 

    Background: HSP90 proteins are essential molecular chaperones involved in signal transduction, cell cycle control, stress management, and folding, degradation, and transport of proteins. HSP90 proteins have been found in a variety of organisms suggesting that they are ancient and conserved. In...

  • Genetic defects in the human glycome. Freeze, Hudson H. // Nature Reviews Genetics;Jul2006, Vol. 7 Issue 7, p537 

    The spectrum of all glycan structures — the glycome — is immense. In humans, its size is orders of magnitude greater than the number of proteins that are encoded by the genome, one percent of which encodes proteins that make, modify, localize or bind sugar chains, which are known...

  • Host cell proteins binding to the encapsidation signal ℇ in hepatitis B virus RNA. Shin, H. J.; Kim, S. S.; Cho, Y. H.; Lee, S. G.; Rho, H. M. // Archives of Virology;Mar2002, Vol. 147 Issue 3, p471 

    Summary. The highly conserved encapsidation signal (ℇ) of hepatitis B viral (HBV) pregenomic RNA has been reported as an essential component for encapsidation and protein priming of HBV polymerase. Here, we report that two HBV ℇ RNA-binding host proteins (80 and 43 kDa) and a...

  • Plastid chaperonin proteins Cpn60α and Cpn60β are required for plastid division in Arabidopsis thaliana. Suzuki, Kenji; Nakanishi, Hiromitsu; Bower, Joyce; Yoder, David W.; Osteryoung, Katherine W.; Shin-ya Miyagishima // BMC Plant Biology;2009, Vol. 9, Special section p1 

    Background: Plastids arose from a free-living cyanobacterial endosymbiont and multiply by binary division as do cyanobacteria. Plastid division involves nucleus-encoded homologs of cyanobacterial division proteins such as FtsZ, MinD, MinE, and ARC6. However, homologs of many other cyanobacterial...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics