Gene Symbol: NHP6A
Description: high-mobility group nucleosome-binding protein
Alias: high-mobility group nucleosome-binding protein
Species: Saccharomyces cerevisiae S288c

Top Publications

  1. Costigan C, Kolodrubetz D, Snyder M. NHP6A and NHP6B, which encode HMG1-like proteins, are candidates for downstream components of the yeast SLT2 mitogen-activated protein kinase pathway. Mol Cell Biol. 1994;14:2391-403 pubmed
    ..Genes which in multiple copies suppress the synthetic lethality of slk1-1 spa2-delta were identified, and one, the NHP6A gene, has been extensively characterized...
  2. Paull T, Carey M, Johnson R. Yeast HMG proteins NHP6A/B potentiate promoter-specific transcriptional activation in vivo and assembly of preinitiation complexes in vitro. Genes Dev. 1996;10:2769-81 pubmed
    Nonhistone proteins 6A and 6B (NHP6A/B) are nonsequence-specific DNA-binding proteins from Saccharomyces cerevisiae that are related structurally and functionally to the mammalian high mobility group proteins 1 and 2...
  3. Kruppa M, Moir R, Kolodrubetz D, Willis I. Nhp6, an HMG1 protein, functions in SNR6 transcription by RNA polymerase III in S. cerevisiae. Mol Cell. 2001;7:309-18 pubmed
    b>Nhp6A and Nhp6B are HMG1-like proteins required for the growth of S. cerevisiae at elevated temperatures...
  4. Ruone S, Rhoades A, Formosa T. Multiple Nhp6 molecules are required to recruit Spt16-Pob3 to form yFACT complexes and to reorganize nucleosomes. J Biol Chem. 2003;278:45288-95 pubmed
    ..These results suggest that Nhp6 and the related high mobility group B proteins may have a general role in promoting rearrangements of chromatin by initiating the destabilization of core nucleosomal structure. ..
  5. Kolodrubetz D, Haggren W, Burgum A. Amino-terminal sequence of a Saccharomyces cerevisiae nuclear protein, NHP6, shows significant identity to bovine HMG1. FEBS Lett. 1988;238:175-9 pubmed
    ..Importantly, the amino-terminal sequence of one of the proteins, NHP6, has significant (60%) identity with a stretch of amino acids in calf thymus HMG1. ..
  6. Yen Y, Wong B, Johnson R. Determinants of DNA binding and bending by the Saccharomyces cerevisiae high mobility group protein NHP6A that are important for its biological activities. Role of the unique N terminus and putative intercalating methionine. J Biol Chem. 1998;273:4424-35 pubmed
    The non-histone proteins 6A/B (NHP6A/B) of Saccharomyces cerevisiae are high mobility group proteins that bind and severely bend DNA of mixed sequence...
  7. Fragiadakis G, Tzamarias D, Alexandraki D. Nhp6 facilitates Aft1 binding and Ssn6 recruitment, both essential for FRE2 transcriptional activation. EMBO J. 2004;23:333-42 pubmed
    We found Nhp6a/b yeast HMG-box chromatin-associated architectural factors and Ssn6 (Cyc8) corepressor to be crucial transcriptional coactivators of FRE2 gene...
  8. Szerlong H, Saha A, Cairns B. The nuclear actin-related proteins Arp7 and Arp9: a dimeric module that cooperates with architectural proteins for chromatin remodeling. EMBO J. 2003;22:3175-87 pubmed
    ..We propose that Arp7/9 dimers function with DNA bending proteins to facilitate proper chromatin architecture and complex- complex interactions. ..
  9. Giavara S, Kosmidou E, Hande M, Bianchi M, Morgan A, d Adda di Fagagna F, et al. Yeast Nhp6A/B and mammalian Hmgb1 facilitate the maintenance of genome stability. Curr Biol. 2005;15:68-72 pubmed
    Saccharomyces cerevisiae Nhp6A and Nhp6B are chromatin architectural factors that belong to the high-mobility group box (HMGB) superfamily and appear to be functionally related to mammalian Hmgb1...

More Information


  1. Zhang J, McCauley M, Maher L, Williams M, Israeloff N. Basic N-terminus of yeast Nhp6A regulates the mechanism of its DNA flexibility enhancement. J Mol Biol. 2012;416:10-20 pubmed publisher
    ..to quantitatively characterize the bend angle distributions of DNA complexes with human HMGB2(Box A), yeast Nhp6A, and two chimeric mutants of these proteins...
  2. Stillman D. Nhp6: a small but powerful effector of chromatin structure in Saccharomyces cerevisiae. Biochim Biophys Acta. 2010;1799:175-80 pubmed publisher
    ..The FACT complex may provide a paradigm for how Nhp6 functions with chromatin factors, as Nhp6 allows Spt16-Pob3 to bind to and reorganize nucleosomes in vitro. ..
  3. Skoko D, Wong B, Johnson R, Marko J. Micromechanical analysis of the binding of DNA-bending proteins HMGB1, NHP6A, and HU reveals their ability to form highly stable DNA-protein complexes. Biochemistry. 2004;43:13867-74 pubmed
    The mechanical response generated by binding of the nonspecific DNA-bending proteins HMGB1, NHP6A, and HU to single tethered 48.5 kb lambda-DNA molecules is investigated using DNA micromanipulation...
  4. Brewster N, Johnston G, Singer R. A bipartite yeast SSRP1 analog comprised of Pob3 and Nhp6 proteins modulates transcription. Mol Cell Biol. 2001;21:3491-502 pubmed
    ..We show here that Nhp6a and Nhp6b, small HMG box proteins with overlapping functions in yeast, associate with the CP complex and mediate ..
  5. Moreira J, Holmberg S. Chromatin-mediated transcriptional regulation by the yeast architectural factors NHP6A and NHP6B. EMBO J. 2000;19:6804-13 pubmed
    The Saccharomyces cerevisiae NHP6A and NHP6B proteins are chromatin architectural factors, functionally and structurally related to the mammalian high mobility group (HMG)-1 and -2 proteins, a family of non-sequence-specific DNA binding ..
  6. Giuntoli R, Linzer N, Banigan E, Sing C, de la Cruz M, Graham J, et al. DNA-Segment-Facilitated Dissociation of Fis and NHP6A from DNA Detected via Single-Molecule Mechanical Response. J Mol Biol. 2015;427:3123-36 pubmed publisher
    ..We also show data for the yeast HMGB protein NHP6A showing a similar DNA-concentration-dependent dissociation effect, with faster rates suggesting generally weaker ..
  7. Formosa T, Eriksson P, Wittmeyer J, Ginn J, Yu Y, Stillman D. Spt16-Pob3 and the HMG protein Nhp6 combine to form the nucleosome-binding factor SPN. EMBO J. 2001;20:3506-17 pubmed
    ..SPT16 and POB3 display strong genetic interactions with NHP6A/B, which encodes an HMG1 motif, suggesting that these gene products function coordinately in vivo...
  8. Hanover J, Love D, DeAngelis N, O Kane M, Lima Miranda R, Schulz T, et al. The High Mobility Group Box Transcription Factor Nhp6Ap enters the nucleus by a calmodulin-dependent, Ran-independent pathway. J Biol Chem. 2007;282:33743-51 pubmed
    ..Calmodulin and DNA exhibit mutually exclusive binding to NHP6A, indicating that the directionality of Nhp6Ap nuclear accumulation may be driven by DNA-dependent dissociation of ..
  9. Coats J, Lin Y, Rueter E, Maher L, Rasnik I. Single-molecule FRET analysis of DNA binding and bending by yeast HMGB protein Nhp6A. Nucleic Acids Res. 2013;41:1372-81 pubmed publisher
    ..DNA 'softening' is explored here by single-molecule fluorescence resonance energy transfer studies of single yeast Nhp6A (yNhp6A) proteins binding to short DNA duplexes...
  10. Biswas D, Dutta Biswas R, Stillman D. Chd1 and yFACT act in opposition in regulating transcription. Mol Cell Biol. 2007;27:6279-87 pubmed
    ..Although human Chd1 has been shown to bind to H3-K4-Me, we discuss evidence arguing that yeast Chd1 binds to neither H3-K4-Me nor H3-K36-Me. ..
  11. Hauer M, Seeber A, Singh V, Thierry R, Sack R, Amitai A, et al. Histone degradation in response to DNA damage enhances chromatin dynamics and recombination rates. Nat Struct Mol Biol. 2017;24:99-107 pubmed publisher
    ..Thus, we propose that a generalized reduction in nucleosome occupancy is an integral part of the DNA damage response in yeast that provides mechanisms for enhanced chromatin mobility and homology search. ..
  12. Biswas D, Yu Y, Prall M, Formosa T, Stillman D. The yeast FACT complex has a role in transcriptional initiation. Mol Cell Biol. 2005;25:5812-22 pubmed
    ..Thus, yFACT functions in establishing transcription initiation complexes in addition to the previously described role in elongation. ..
  13. Yu Y, Eriksson P, Bhoite L, Stillman D. Regulation of TATA-binding protein binding by the SAGA complex and the Nhp6 high-mobility group protein. Mol Cell Biol. 2003;23:1910-21 pubmed
  14. Biswas D, Imbalzano A, Eriksson P, Yu Y, Stillman D. Role for Nhp6, Gcn5, and the Swi/Snf complex in stimulating formation of the TATA-binding protein-TFIIA-DNA complex. Mol Cell Biol. 2004;24:8312-21 pubmed
    ..Consistent with the idea that Nhp6, Gcn5, and Swi/Snf have overlapping functions in vivo, nhp6a nhp6b gcn5 mutants had a severe growth defect, and mutations in both nhp6a nhp6b swi2 and gcn5 swi2 strains were ..
  15. Biswas D, Yu Y, Mitra D, Stillman D. Genetic interactions between Nhp6 and Gcn5 with Mot1 and the Ccr4-Not complex that regulate binding of TATA-binding protein in Saccharomyces cerevisiae. Genetics. 2006;172:837-49 pubmed
    ..Chromatin immunoprecipitation experiments show decreased binding of TBP to promoters in mot1 mutants and a further decrease when combined with either nhp6ab or gcn5 mutations. ..
  16. Sampath V, Liu B, Tafrov S, Srinivasan M, Rieger R, Chen E, et al. Biochemical characterization of Hpa2 and Hpa3, two small closely related acetyltransferases from Saccharomyces cerevisiae. J Biol Chem. 2013;288:21506-13 pubmed publisher
    ..These results suggest that Hpa2 and Hpa3 are similar but distinct acetyltransferases that might have overlapping roles with other known acetyltransferases in vivo in acetylating histones and other small proteins. ..
  17. Düring L, Thorsen M, Petersen D, Køster B, Jensen T, Holmberg S. MRN1 implicates chromatin remodeling complexes and architectural factors in mRNA maturation. PLoS ONE. 2012;7:e44373 pubmed publisher
    ..deficient for the function of the chromatin remodeling factor RSC and the chromatin architectural proteins Nhp6A/Nhp6B, accumulate intron-containing pre-mRNA at the restrictive temperature...
  18. McDonald S, Close D, Xin H, Formosa T, Hill C. Structure and biological importance of the Spn1-Spt6 interaction, and its regulatory role in nucleosome binding. Mol Cell. 2010;40:725-35 pubmed publisher
    ..These data thereby reveal the structural and biochemical bases of molecular interactions that function in the maintenance of chromatin structure. ..
  19. Lemieux K, Larochelle M, Gaudreau L. Variant histone H2A.Z, but not the HMG proteins Nhp6a/b, is essential for the recruitment of Swi/Snf, Mediator, and SAGA to the yeast GAL1 UAS(G). Biochem Biophys Res Commun. 2008;369:1103-7 pubmed publisher
    ..Here, we investigated the role of two different chromatin components, the histone variant H2A.Z and HMG proteins Nhp6a/b, in regulating GAL1 gene expression...
  20. Cesarini E, D Alfonso A, Camilloni G. H4K16 acetylation affects recombination and ncRNA transcription at rDNA in Saccharomyces cerevisiae. Mol Biol Cell. 2012;23:2770-81 pubmed publisher
    ..Here we provide evidence that a single, rapid, and reversible posttranslational modification-the acetylation of the H4K16 residue-is involved in the coordination of transcription and recombination at rDNA. ..
  21. Xin H, Takahata S, Blanksma M, McCullough L, Stillman D, Formosa T. yFACT induces global accessibility of nucleosomal DNA without H2A-H2B displacement. Mol Cell. 2009;35:365-76 pubmed publisher
    ..We propose that yFACT promotes a reversible transition between two nucleosomal forms, and that this activity contributes to the establishment and maintenance of the chromatin barrier as well as to overcoming it. ..
  22. Dowell N, Sperling A, Mason M, Johnson R. Chromatin-dependent binding of the S. cerevisiae HMGB protein Nhp6A affects nucleosome dynamics and transcription. Genes Dev. 2010;24:2031-42 pubmed publisher
    The Saccharomyces cerevisiae protein Nhp6A is a model for the abundant and multifunctional high-mobility group B (HMGB) family of chromatin-associated proteins...
  23. Formosa T, Ruone S, Adams M, Olsen A, Eriksson P, Yu Y, et al. Defects in SPT16 or POB3 (yFACT) in Saccharomyces cerevisiae cause dependence on the Hir/Hpc pathway: polymerase passage may degrade chromatin structure. Genetics. 2002;162:1557-71 pubmed
    ..Mutations in POB3, but not in NHP6A/B, also display strong synthetic defects with hir/hpc mutations...
  24. Martin M, Gerlach V, Brow D. A novel upstream RNA polymerase III promoter element becomes essential when the chromatin structure of the yeast U6 RNA gene is altered. Mol Cell Biol. 2001;21:6429-39 pubmed
    ..We conclude that the (dT-dA)(7) tract and Nhp6 cooperate to direct productive transcription complex assembly on SNR6 in vivo. ..
  25. Sebastian N, Bystry E, Becker N, Maher L. Enhancement of DNA flexibility in vitro and in vivo by HMGB box A proteins carrying box B residues. Biochemistry. 2009;48:2125-34 pubmed publisher
    ..These results demonstrate important roles for cationic leader amino acids in HMGB folding, DNA interaction, and DNA bending. ..
  26. Hepp M, Smolle M, Gidi C, Amigo R, Valenzuela N, Arriagada A, et al. Role of Nhp6 and Hmo1 in SWI/SNF occupancy and nucleosome landscape at gene regulatory regions. Biochim Biophys Acta Gene Regul Mech. 2017;1860:316-326 pubmed publisher
    ..Our results suggest that, besides the ability to stimulate SWI/SNF activity, these HMG proteins are able to assist the loading of this complex onto gene regulatory regions. ..
  27. Eriksson P, Biswas D, Yu Y, Stewart J, Stillman D. TATA-binding protein mutants that are lethal in the absence of the Nhp6 high-mobility-group protein. Mol Cell Biol. 2004;24:6419-29 pubmed
    ..These results challenge the widely held belief that 6-AU sensitivity results from a defect in transcriptional elongation. ..
  28. Braglia P, Dugas S, Donze D, Dieci G. Requirement of Nhp6 proteins for transcription of a subset of tRNA genes and heterochromatin barrier function in Saccharomyces cerevisiae. Mol Cell Biol. 2007;27:1545-57 pubmed
    ..Our data suggest that Nhp6 proteins are important components of Pol III chromatin templates that contribute both to the robustness of tRNA gene expression and to positional effects of Pol III transcription complexes. ..
  29. Labazi M, Jaafar L, Flores Rozas H. Modulation of the DNA-binding activity of Saccharomyces cerevisiae MSH2-MSH6 complex by the high-mobility group protein NHP6A, in vitro. Nucleic Acids Res. 2009;37:7581-9 pubmed publisher
    ..In yeast, the closest homologs of HMGB1 are NHP6A and NHP6B. These proteins have been shown to be required for genome stability maintenance and mutagenesis control...
  30. Sidorova J, Breeden L. The MSN1 and NHP6A genes suppress SWI6 defects in Saccharomyces cerevisiae. Genetics. 1999;151:45-55 pubmed
    ..We found that MSN1, which encodes a transcriptional activator, and NHP6A, which encodes an HMG-like protein, are able to suppress defective Swi6 function...
  31. Durano D, Lukács A, Di Felice F, Micheli G, Camilloni G. A novel role for Nhp6 proteins in histone gene regulation in Saccharomyces cerevisiae. Int J Biochem Cell Biol. 2017;83:76-83 pubmed publisher
    ..Our observations allow us to incorporate Nhp6 proteins into the large group of chromatin factors that tightly regulate histone gene expression. ..
  32. Paull T, Johnson R. DNA looping by Saccharomyces cerevisiae high mobility group proteins NHP6A/B. Consequences for nucleoprotein complex assembly and chromatin condensation. J Biol Chem. 1995;270:8744-54 pubmed
    ..as measured by the ability to stimulate invertasome formation, and show that these are the previously identified NHP6A/B proteins...
  33. Becker N, Maher L. High-resolution mapping of architectural DNA binding protein facilitation of a DNA repression loop in Escherichia coli. Proc Natl Acad Sci U S A. 2015;112:7177-82 pubmed publisher
    ..proteins, such as Escherichia coli heat unstable and Saccharomyces cerevisiae non-histone chromosomal protein 6A (Nhp6A), facilitate lac repressor (LacI) repression loops in E. coli...
  34. Ciuffetta A, Salerno D, Camilloni G, Venditti S. Sir2 is involved in the transcriptional modulation of NHP6A in Saccharomyces cerevisiae. Biochem Biophys Res Commun. 2015;461:42-6 pubmed publisher
    ..b>Nhp6a is an abundant HMG-like protein in yeast, which has a role in transcription by modulating chromatin structure and ..
  35. Andreadis C, Nikolaou C, Fragiadakis G, Tsiliki G, Alexandraki D. Rad9 interacts with Aft1 to facilitate genome surveillance in fragile genomic sites under non-DNA damage-inducing conditions in S. cerevisiae. Nucleic Acids Res. 2014;42:12650-67 pubmed publisher
    ..Thus, our findings suggest that Rad9 functions together with Aft1 on DNA damage-prone chromatin to facilitate genome surveillance, thereby ensuring rapid and effective response to possible DNA damage events. ..
  36. Kassavetis G, Steiner D. Nhp6 is a transcriptional initiation fidelity factor for RNA polymerase III transcription in vitro and in vivo. J Biol Chem. 2006;281:7445-51 pubmed
    ..In this paper we show that Nhp6a, an abundant high mobility group B (HMGB) family, non-sequence-specific DNA-binding protein in Saccharomyces ..
  37. Yu Y, Eriksson P, Stillman D. Architectural transcription factors and the SAGA complex function in parallel pathways to activate transcription. Mol Cell Biol. 2000;20:2350-7 pubmed
    ..We also demonstrate that the Nhp6 architectural transcription factor, encoded by the redundant NHP6A and NHP6B genes, is required for HO expression...