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  1. Article: Histone Modifications, Internucleosome Dynamics, and DNA Stresses: How They Cooperate to "Functionalize" Nucleosomes.

    Krajewski, Wladyslaw A

    Frontiers in genetics

    2022  Volume 13, Page(s) 873398

    Abstract: Tight packaging of DNA in chromatin severely constrains DNA accessibility and dynamics. In contrast, nucleosomes in active chromatin state are highly flexible, can exchange their histones, and are virtually "transparent" to RNA polymerases, which ... ...

    Abstract Tight packaging of DNA in chromatin severely constrains DNA accessibility and dynamics. In contrast, nucleosomes in active chromatin state are highly flexible, can exchange their histones, and are virtually "transparent" to RNA polymerases, which transcribe through gene bodies at rates comparable to that of naked DNA. Defining mechanisms that revert nucleosome repression, in addition to their value for basic science, is of key importance for the diagnosis and treatment of genetic diseases. Chromatin activity is largely regulated by histone posttranslational modifications, ranging from small chemical groups up to the yet understudied "bulky" ubiquitylation and sumoylation. However, it is to be revealed how histone marks are "translated" to permissive or repressive changes in nucleosomes: it is a general opinion that histone modifications act primarily as "signals" for recruiting the regulatory proteins or as a "neutralizer" of electrostatic shielding of histone tails. Here, we would like to discuss recent evidence suggesting that histone ubiquitylation, in a DNA stress-dependent manner, can directly regulate the dynamics of the nucleosome and their primary structure and can promote nucleosome decomposition to hexasome particles or additionally stabilize nucleosomes against unwrapping. In addition, nucleosome repression/ derepression studies are usually performed with single mononucleosomes as a model. We would like to review and discuss recent findings showing that internucleosomal interactions could strongly modulate the dynamics and rearrangements of nucleosomes. Our hypothesis is that bulky histone modifications, nucleosome inherent dynamics, internucleosome interactions, and DNA torsions could act in cooperation to orchestrate the formation of different dynamic states of arrayed nucleosomes and thus promote chromatin functionality and diversify epigenetic programming methods.
    Language English
    Publishing date 2022-04-28
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2606823-0
    ISSN 1664-8021
    ISSN 1664-8021
    DOI 10.3389/fgene.2022.873398
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  2. Article ; Online: Ubiquitylation: How Nucleosomes Use Histones to Evict Histones.

    Krajewski, Wladyslaw A

    Trends in cell biology

    2019  Volume 29, Issue 9, Page(s) 689–694

    Abstract: Steric hindrances by bulky histone modifications (such as ubiquitylation) could destabilize and remodel canonical nucleosome structure. This highlights a novel mechanism by which bulky modifications directly regulate chromatin, distinct from the more ... ...

    Abstract Steric hindrances by bulky histone modifications (such as ubiquitylation) could destabilize and remodel canonical nucleosome structure. This highlights a novel mechanism by which bulky modifications directly regulate chromatin, distinct from the more generally accepted roles of histone modifications in the recruitment of downstream effectors and histone charge shielding.
    MeSH term(s) Chromatin/metabolism ; Histones/metabolism ; Humans ; Nucleosomes/metabolism ; Protein Processing, Post-Translational ; Ubiquitination
    Chemical Substances Chromatin ; Histones ; Nucleosomes
    Language English
    Publishing date 2019-07-02
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 30122-x
    ISSN 1879-3088 ; 0962-8924
    ISSN (online) 1879-3088
    ISSN 0962-8924
    DOI 10.1016/j.tcb.2019.06.002
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  3. Article ; Online: "Direct" and "Indirect" Effects of Histone Modifications: Modulation of Sterical Bulk as a Novel Source of Functionality.

    Krajewski, Wladyslaw A

    BioEssays : news and reviews in molecular, cellular and developmental biology

    2019  Volume 42, Issue 1, Page(s) e1900136

    Abstract: The chromatin-regulatory principles of histone post-translational modifications (PTMs) are discussed with a focus on the potential alterations in chromatin functional state due to steric and mechanical constraints imposed by bulky histone modifications ... ...

    Abstract The chromatin-regulatory principles of histone post-translational modifications (PTMs) are discussed with a focus on the potential alterations in chromatin functional state due to steric and mechanical constraints imposed by bulky histone modifications such as ubiquitin and SUMO. In the classical view, PTMs operate as recruitment platforms for histone "readers," and as determinants of chromatin array compaction. Alterations of histone charges by "small" chemical modifications (e.g., acetylation, phosphorylation) could regulate nucleosome spontaneous dynamics without globally affecting nucleosome structure. These fluctuations in nucleosome wrapping can be exploited by chromatin-processing machinery. In contrast, ubiquitin and SUMO are comparable in size to histones, and it seems logical that these PTMs could conflict with canonical nucleosome organization. An experimentally testable hypothesis that by adding sterical bulk these PTMs can robustly alter nucleosome primary structure is proposed. The model presented here stresses the diversity of mechanisms by which histone PTMs regulate chromatin dynamics, primary structure and, hence, functionality.
    MeSH term(s) Acetylation ; Chromatin Assembly and Disassembly ; Histones/chemistry ; Histones/metabolism ; Models, Biological ; Nucleosomes/chemistry ; Nucleosomes/genetics ; Nucleosomes/metabolism ; Phosphorylation ; Protein Processing, Post-Translational ; Sumoylation ; Transcription, Genetic ; Ubiquitination
    Chemical Substances Histones ; Nucleosomes
    Language English
    Publishing date 2019-12-05
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 50140-2
    ISSN 1521-1878 ; 0265-9247
    ISSN (online) 1521-1878
    ISSN 0265-9247
    DOI 10.1002/bies.201900136
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  4. Article ; Online: The intrinsic stability of H2B-ubiquitylated nucleosomes and their in vitro assembly/disassembly by histone chaperone NAP1.

    Krajewski, Wladyslaw A

    Biochimica et biophysica acta. General subjects

    2019  Volume 1864, Issue 3, Page(s) 129497

    Abstract: Background: Apart the gene-regulatory functions as docking sites for histone 'readers', some histone modifications could directly affect nucleosome structure. The H2BK34-ubiquitylation deposited by MOF-MSL complex, increases nucleosome dynamics in vitro ...

    Abstract Background: Apart the gene-regulatory functions as docking sites for histone 'readers', some histone modifications could directly affect nucleosome structure. The H2BK34-ubiquitylation deposited by MOF-MSL complex, increases nucleosome dynamics in vitro and promotes donation of one H2A/H2B dimer to histone acceptors.
    Methods: We evaluated temperature-depended stability of H2BK34-ubiquitylated nucleosomes under 'physiological' ionic conditions in the presence or absence of histone acceptor, and examined assembly and disassembly of ubiquitylated nucleosomes in vitro by recombinant mouse NAP1.
    Results: H2BK34ub modification is sufficient to promote selective eviction of only one H2A/H2B dimer independently of histone-binding agents. Despite the robust H2A/H2B dimer-displacement effect of mNAP1 with the H2BK34ub (but not unmodified) nucleosomes, NAP1 could assemble symmetrically- or asymmetrically ubiquitylated nucleosomes under 'physiological' conditions in vitro.
    Conclusions and general significance: The increased mobility of one nucleosomal H2A/H2B dimer is an intrinsic nucleosome destabilizing property of H2BK34 ubiquitylation that has the intranucleosome bases. The ability of NAP to reasonably efficiently assemble H2BK34-ubiquitylated nucleosomes supposes a potential mechanism for deposition/distribution of H2BK34ub mark in the MOF-MSL independent manner (for example, during histone dimer exchange upon transcription elongation).
    MeSH term(s) Animals ; Chromatin/metabolism ; Histone Chaperones/metabolism ; Histone Chaperones/physiology ; Histones/metabolism ; Histones/physiology ; Mice ; Naphthalenes/metabolism ; Nucleosome Assembly Protein 1/chemistry ; Nucleosome Assembly Protein 1/genetics ; Nucleosome Assembly Protein 1/metabolism ; Nucleosomes/metabolism ; Oligopeptides/metabolism ; Oligopeptides/physiology ; Protein Binding ; Protein Processing, Post-Translational ; Ubiquitination/physiology
    Chemical Substances Chromatin ; Histone Chaperones ; Histones ; Naphthalenes ; Nucleosome Assembly Protein 1 ; Nucleosomes ; Oligopeptides ; nucleic acid probe 1
    Language English
    Publishing date 2019-11-27
    Publishing country Netherlands
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 60-7
    ISSN 1872-8006 ; 1879-2596 ; 1879-260X ; 1879-2642 ; 1879-2618 ; 1879-2650 ; 0006-3002 ; 0005-2728 ; 0005-2736 ; 0304-4165 ; 0167-4838 ; 1388-1981 ; 0167-4889 ; 0167-4781 ; 0304-419X ; 1570-9639 ; 0925-4439 ; 1874-9399
    ISSN (online) 1872-8006 ; 1879-2596 ; 1879-260X ; 1879-2642 ; 1879-2618 ; 1879-2650
    ISSN 0006-3002 ; 0005-2728 ; 0005-2736 ; 0304-4165 ; 0167-4838 ; 1388-1981 ; 0167-4889 ; 0167-4781 ; 0304-419X ; 1570-9639 ; 0925-4439 ; 1874-9399
    DOI 10.1016/j.bbagen.2019.129497
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  5. Article: Mobilization of hyperacetylated mononucleosomes by purified yeast ISW2 in vitro

    Krajewski, Wladyslaw A

    Archives of biochemistry and biophysics. 2016 Feb. 01, v. 591

    2016  

    Abstract: ... of nucleosomal H4 – such, that removal of H4 termini abolishes ISWI remodeling. Acetylation of H4 termini is ... of highly acetylated histone isoforms in response to TSA treatment. However, such ‘native’ histone ...

    Abstract Catalytic activity of ISWI chromatin remodelers, which regulate nucleosome positioning on the DNA, depends on interactions of the putative acidic patch in ISWI helicase domain with the N-termini of nucleosomal H4 – such, that removal of H4 termini abolishes ISWI remodeling. Acetylation of H4 termini is also known to disrupt H4 interactions with acidic protein surfaces, and thus, histone acetylation could potentially impede ISWI functions. Since active chromatin in vivo is hyperacetylated, it is important to clarify if ISWI activities can function on the in vivo hyperacetylated nucleosomes. We evaluated if purified yeast ISW2 can act on mononucleosomes in which all four core histones are highly acetylated. Mononucleosomes were assembled using purified histones from mammalian CV1 cells grown in the presence of deacetylase inhibitor Trichostatin A (TSA). The CV1 cell line is characterized by fast kinetic of accumulation of highly acetylated histone isoforms in response to TSA treatment. However, such ‘native’ histone hyperacetylation had no apparent effects on the nucleosome remodeling propensities, suggesting that histone hyperacetylation does not necessarily block ISWI functions and that ISWI enzymes can function on active chromatin as well.
    Keywords DNA ; acetylation ; catalytic activity ; enzymes ; histones ; mammals ; nucleosomes ; yeasts
    Language English
    Dates of publication 2016-0201
    Size p. 1-6.
    Publishing place Elsevier Inc.
    Document type Article
    ZDB-ID 523-x
    ISSN 1096-0384 ; 0003-9861
    ISSN (online) 1096-0384
    ISSN 0003-9861
    DOI 10.1016/j.abb.2015.12.002
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  6. Article ; Online: Effects of DNA Superhelical Stress on the Stability of H2B-Ubiquitylated Nucleosomes.

    Krajewski, Wladyslaw A

    Journal of molecular biology

    2018  Volume 430, Issue 24, Page(s) 5002–5014

    Abstract: ... of the nucleosomal H2A-H2B dimers and promote nucleosome conversion to a hexasome particle [Krajewski et al. (2018 ...

    Abstract On the nucleosome level, histone posttranslational modifications function mainly as the regulatory signals; in addition, some posttranslational modifications can enhance nucleosome stochastic folding, which is restricted in "canonic" nucleosomes. Recently, it has been shown in vitro that symmetric or asymmetric nucleosome ubiquitylation at H2BK34 (and H2BK120, to a lesser extent) can destabilize one of the nucleosomal H2A-H2B dimers and promote nucleosome conversion to a hexasome particle [Krajewski et al. (2018). Nucleic Acids Res., 46, 7631-7642]. Such lability of H2Bub nucleosomes raises a question of whether they could accommodate transient changes in DNA torsional tensions, which are generated by virtually any process that manipulates DNA strands. Using positively or negatively supercoiled DNA minicircles and homogeneously-modified H2Bub histones, we have found that DNA topology could strongly and selectively affect nucleosome stability depending on its ubiquitylation state (here the term "nucleosome stability" means the nucleosome property to maintain its structural integrity and dynamics characteristic to "canonic" nucleosomes). The results point to a role for H2B ubiquitylation in amplifying or mitigating the effects of a DNA torque on the nucleosome stability and dynamics.
    MeSH term(s) DNA, Superhelical/metabolism ; Histones/metabolism ; Models, Molecular ; Molecular Conformation ; Nucleosomes/chemistry ; Nucleosomes/metabolism ; Protein Processing, Post-Translational ; Ubiquitination
    Chemical Substances DNA, Superhelical ; Histones ; Nucleosomes
    Language English
    Publishing date 2018-09-26
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 80229-3
    ISSN 1089-8638 ; 0022-2836
    ISSN (online) 1089-8638
    ISSN 0022-2836
    DOI 10.1016/j.jmb.2018.09.014
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  7. Article: “Direct” and “Indirect” Effects of Histone Modifications: Modulation of Sterical Bulk as a Novel Source of Functionality

    Krajewski, Wladyslaw A

    BioEssays. 2020 Jan., v. 42, no. 1

    2020  

    Abstract: The chromatin‐regulatory principles of histone post‐translational modifications (PTMs) are discussed with a focus on the potential alterations in chromatin functional state due to steric and mechanical constraints imposed by bulky histone modifications ... ...

    Abstract The chromatin‐regulatory principles of histone post‐translational modifications (PTMs) are discussed with a focus on the potential alterations in chromatin functional state due to steric and mechanical constraints imposed by bulky histone modifications such as ubiquitin and SUMO. In the classical view, PTMs operate as recruitment platforms for histone “readers,” and as determinants of chromatin array compaction. Alterations of histone charges by “small” chemical modifications (e.g., acetylation, phosphorylation) could regulate nucleosome spontaneous dynamics without globally affecting nucleosome structure. These fluctuations in nucleosome wrapping can be exploited by chromatin‐processing machinery. In contrast, ubiquitin and SUMO are comparable in size to histones, and it seems logical that these PTMs could conflict with canonical nucleosome organization. An experimentally testable hypothesis that by adding sterical bulk these PTMs can robustly alter nucleosome primary structure is proposed. The model presented here stresses the diversity of mechanisms by which histone PTMs regulate chromatin dynamics, primary structure and, hence, functionality.
    Keywords acetylation ; histones ; models ; nucleosomes ; phosphorylation ; ubiquitin
    Language English
    Dates of publication 2020-01
    Publishing place John Wiley & Sons, Ltd
    Document type Article
    Note NAL-AP-2-clean ; JOURNAL ARTICLE
    ZDB-ID 50140-2
    ISSN 1521-1878 ; 0265-9247
    ISSN (online) 1521-1878
    ISSN 0265-9247
    DOI 10.1002/bies.201900136
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  8. Article: The intrinsic stability of H2B-ubiquitylated nucleosomes and their in vitro assembly/disassembly by histone chaperone NAP1

    Krajewski, Wladyslaw A

    Biochimica et biophysica acta. 2020 Mar., v. 1864, no. 3

    2020  

    Abstract: Apart the gene-regulatory functions as docking sites for histone ‘readers’, some histone modifications could directly affect nucleosome structure. The H2BK34-ubiquitylation deposited by MOF-MSL complex, increases nucleosome dynamics in vitro and promotes ...

    Abstract Apart the gene-regulatory functions as docking sites for histone ‘readers’, some histone modifications could directly affect nucleosome structure. The H2BK34-ubiquitylation deposited by MOF-MSL complex, increases nucleosome dynamics in vitro and promotes donation of one H2A/H2B dimer to histone acceptors.We evaluated temperature-depended stability of H2BK34-ubiquitylated nucleosomes under ‘physiological’ ionic conditions in the presence or absence of histone acceptor, and examined assembly and disassembly of ubiquitylated nucleosomes in vitro by recombinant mouse NAP1.H2BK34ub modification is sufficient to promote selective eviction of only one H2A/H2B dimer independently of histone-binding agents. Despite the robust H2A/H2B dimer-displacement effect of mNAP1 with the H2BK34ub (but not unmodified) nucleosomes, NAP1 could assemble symmetrically- or asymmetrically ubiquitylated nucleosomes under ‘physiological’ conditions in vitro.The increased mobility of one nucleosomal H2A/H2B dimer is an intrinsic nucleosome destabilizing property of H2BK34 ubiquitylation that has the intranucleosome bases. The ability of NAP to reasonably efficiently assemble H2BK34-ubiquitylated nucleosomes supposes a potential mechanism for deposition/distribution of H2BK34ub mark in the MOF-MSL independent manner (for example, during histone dimer exchange upon transcription elongation).
    Keywords histone code ; histones ; mice ; nucleosomes
    Language English
    Dates of publication 2020-03
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 840755-1
    ISSN 0304-4165
    ISSN 0304-4165
    DOI 10.1016/j.bbagen.2019.129497
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  9. Article: The Effects of Histone H2B ubiquitylations and H3K79me

    Huynh, Mai T / Sengupta, Bhaswati / Krajewski, Wladyslaw A / Lee, Tae-Hee

    bioRxiv : the preprint server for biology

    2023  

    Abstract: Post-translational modifications of histone proteins often mediate gene regulation by altering the global and local stability of the nucleosome, the basic gene-packing unit of eukaryotes. We employed semi-synthetic approaches to introduce histone H2B ... ...

    Abstract Post-translational modifications of histone proteins often mediate gene regulation by altering the global and local stability of the nucleosome, the basic gene-packing unit of eukaryotes. We employed semi-synthetic approaches to introduce histone H2B ubiquitylations at K34 (H2BK34ub) and K120 (H2BK120ub) and H3 K79 trimethylation (H3K79me3). With these modified histones, we investigated their effects on the kinetics of transcription elongation by RNA Polymerase II (Pol II) using single-molecule FRET. Pol II pauses at several locations within the nucleosome for a few seconds to minutes, which governs the overall transcription efficiency. We found that H2B ubiquitylations suppress pauses and shorten the pause durations near the nucleosome entry while H3K79me3 shortens the pause durations and increases the rate of RNA elongation near the center of the nucleosome. We also found that H2BK34ub facilitates partial rewrapping of the nucleosome upon Pol II passage. These observations suggest that H2B ubiquitylations promote transcription elongation and help maintain the chromatin structure by inducing and stabilizing nucleosome intermediates and that H3K79me3 facilitates Pol II progression possibly by destabilizing the local structure of the nucleosome. Our results provide the mechanisms of how these modifications coupled by a network of regulatory proteins facilitate transcription in two different regions of the nucleosome and help maintain the chromatin structure during active transcription.
    Language English
    Publishing date 2023-01-05
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2023.01.05.522859
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  10. Article ; Online: Effects of Histone H2B Ubiquitylations and H3K79me

    Huynh, Mai T / Sengupta, Bhaswati / Krajewski, Wladyslaw A / Lee, Tae-Hee

    ACS chemical biology

    2023  Volume 18, Issue 3, Page(s) 537–548

    Abstract: Post-translational modifications of histone proteins often mediate gene regulation by altering the global and local stability of the nucleosome, the basic gene-packing unit of eukaryotes. We employed semisynthetic approaches to introduce histone H2B ... ...

    Abstract Post-translational modifications of histone proteins often mediate gene regulation by altering the global and local stability of the nucleosome, the basic gene-packing unit of eukaryotes. We employed semisynthetic approaches to introduce histone H2B ubiquitylations at K34 (H2BK34ub) and K120 (H2BK120ub) and H3K79 trimethylation (H3K79me3). With these modified histones, we investigated their effects on the kinetics of transcription elongation by RNA polymerase II (Pol II) using single-molecule FRET. Pol II pauses at several locations within the nucleosome for a few seconds to minutes, which governs the overall transcription efficiency. We found that H2B ubiquitylations suppress pauses and shorten the pause durations near the nucleosome entry while H3K79me3 shortens the pause durations and increases the rate of RNA elongation near the center of the nucleosome. We also found that H2BK34ub facilitates partial rewrapping of the nucleosome upon Pol II passage. These observations suggest that H2B ubiquitylations promote transcription elongation and help maintain the chromatin structure by inducing and stabilizing nucleosome intermediates and that H3K79me3 facilitates Pol II progression possibly by destabilizing the local structure of the nucleosome. Our results provide the mechanisms of how these modifications coupled by a network of regulatory proteins facilitate transcription in two different regions of the nucleosome and help maintain the chromatin structure during active transcription.
    MeSH term(s) Histones/metabolism ; Nucleosomes ; Transcription, Genetic ; RNA Polymerase II/chemistry ; Ubiquitination
    Chemical Substances Histones ; Nucleosomes ; RNA Polymerase II (EC 2.7.7.-)
    Language English
    Publishing date 2023-03-01
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Extramural
    ISSN 1554-8937
    ISSN (online) 1554-8937
    DOI 10.1021/acschembio.2c00887
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