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  1. Article ; Online: Different means, same end-heterochromatin formation by RNAi and RNAi-independent RNA processing factors in fission yeast.

    Reyes-Turcu, Francisca E / Grewal, Shiv Is

    Current opinion in genetics & development

    2012  Volume 22, Issue 2, Page(s) 156–163

    Abstract: The assembly of heterochromatin in eukaryotic genomes is critical for diverse chromosomal events including regulation of gene expression, silencing of repetitive DNA elements, proper segregation of chromosomes and maintenance of genomic integrity. ... ...

    Abstract The assembly of heterochromatin in eukaryotic genomes is critical for diverse chromosomal events including regulation of gene expression, silencing of repetitive DNA elements, proper segregation of chromosomes and maintenance of genomic integrity. Previous studies have shown that noncoding RNAs and the RNA interference (RNAi) machinery promote the assembly of heterochromatin that serves as a multipurpose platform for targeting effectors involved in various chromosomal processes. Recent work has revealed that RNAi-independent mechanisms, involving RNA processing activities that utilize both noncoding and coding RNAs, operate in the assembly of heterochromatin. These findings have established that, in addition to coding for proteins, mRNAs also function as signaling molecules that modify chromatin structure by targeting heterochromatin assembly factors.
    MeSH term(s) Animals ; Heterochromatin ; Humans ; RNA Interference ; RNA, Fungal/genetics ; RNA, Messenger/genetics ; Schizosaccharomyces/genetics
    Chemical Substances Heterochromatin ; RNA, Fungal ; RNA, Messenger
    Language English
    Publishing date 2012-01-11
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Intramural ; Review
    ZDB-ID 1077312-5
    ISSN 1879-0380 ; 0959-437X
    ISSN (online) 1879-0380
    ISSN 0959-437X
    DOI 10.1016/j.gde.2011.12.004
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: Different means, same end—heterochromatin formation by RNAi and RNAi-independent RNA processing factors in fission yeast

    Reyes-Turcu, Francisca E / Grewal, Shiv IS

    Current Opinion in Genetics & Development. 2012 Apr., v. 22, no. 2

    2012  

    Abstract: The assembly of heterochromatin in eukaryotic genomes is critical for diverse chromosomal events including regulation of gene expression, silencing of repetitive DNA elements, proper segregation of chromosomes and maintenance of genomic integrity. ... ...

    Abstract The assembly of heterochromatin in eukaryotic genomes is critical for diverse chromosomal events including regulation of gene expression, silencing of repetitive DNA elements, proper segregation of chromosomes and maintenance of genomic integrity. Previous studies have shown that noncoding RNAs and the RNA interference (RNAi) machinery promote the assembly of heterochromatin that serves as a multipurpose platform for targeting effectors involved in various chromosomal processes. Recent work has revealed that RNAi-independent mechanisms, involving RNA processing activities that utilize both noncoding and coding RNAs, operate in the assembly of heterochromatin. These findings have established that, in addition to coding for proteins, mRNAs also function as signaling molecules that modify chromatin structure by targeting heterochromatin assembly factors.
    Keywords DNA ; RNA interference ; Schizosaccharomyces pombe ; genome ; heterochromatin ; messenger RNA ; non-coding RNA
    Language English
    Dates of publication 2012-04
    Size p. 156-163.
    Publishing place Elsevier Ltd
    Document type Article
    ZDB-ID 1077312-5
    ISSN 1879-0380 ; 0959-437X
    ISSN (online) 1879-0380
    ISSN 0959-437X
    DOI 10.1016/j.gde.2011.12.004
    Database NAL-Catalogue (AGRICOLA)

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  3. Article ; Online: Challenges and Strategies in the Development of Radiation Biodosimetry Tests for Patient Management.

    Satyamitra, Merriline / Reyes Turcu, Francisca E / Pantoja-Galicia, Norberto / Wathen, Lynne

    Radiation research

    2021  Volume 196, Issue 5, Page(s) 455–467

    Abstract: The public health and medical response to a radiological or nuclear incident requires the capability to sort, assess, treat, triage and ultimately discharge, as well as to refer or transport people to their next step in medical care. The Public Health ... ...

    Abstract The public health and medical response to a radiological or nuclear incident requires the capability to sort, assess, treat, triage and ultimately discharge, as well as to refer or transport people to their next step in medical care. The Public Health Emergency Medical Countermeasures Enterprise (PHEMCE), directed by the U.S. Department of Health and Human Services (HHS), facilitates a comprehensive, multi-agency effort to develop and deploy radiation biodosimetry tests. Within HHS, discovery and development of biodosimetry tests includes the National Institute of Allergy and Infectious Diseases (NIAID) National Institutes of Health (NIH), the Office of the Assistant Secretary of Preparedness and Response (ASPR), Biomedical Advanced Research and Development Authority (BARDA), and the Food and Drug Administration (FDA) as primary partners in this endeavor. The study of radiation biodosimetry has advanced significantly, with expansion into the fields of cytogenetics, genomics, proteomics, metabolomics, lipidomics and transcriptomics. In addition, expansion of traditional cytogenetic assessment methods using automated platforms, and development of laboratory surge capacity networks have helped to advance biodefense preparedness. This article describes various programs and coordinating efforts between NIAID, BARDA and FDA in the development of radiation biodosimetry approaches to respond to radiological and nuclear threats.
    MeSH term(s) Disaster Planning ; Genomics ; Humans ; National Institute of Allergy and Infectious Diseases (U.S.) ; Radioactive Hazard Release ; Terrorism ; United States
    Language English
    Publishing date 2021-06-17
    Publishing country United States
    Document type Journal Article
    ZDB-ID 80322-4
    ISSN 1938-5404 ; 0033-7587
    ISSN (online) 1938-5404
    ISSN 0033-7587
    DOI 10.1667/RADE-21-00072.1
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Polyubiquitin binding and disassembly by deubiquitinating enzymes.

    Reyes-Turcu, Francisca E / Wilkinson, Keith D

    Chemical reviews

    2009  Volume 109, Issue 4, Page(s) 1495–1508

    MeSH term(s) Catalytic Domain ; Endopeptidases/metabolism ; Humans ; Protein Binding ; Protein Processing, Post-Translational ; Protein Structure, Tertiary ; Structure-Activity Relationship ; Ubiquitins/chemistry ; Ubiquitins/metabolism
    Chemical Substances Ubiquitins ; Endopeptidases (EC 3.4.-)
    Language English
    Publishing date 2009-02-25
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 207949-5
    ISSN 1520-6890 ; 0009-2665
    ISSN (online) 1520-6890
    ISSN 0009-2665
    DOI 10.1021/cr800470j
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Regulation and cellular roles of ubiquitin-specific deubiquitinating enzymes.

    Reyes-Turcu, Francisca E / Ventii, Karen H / Wilkinson, Keith D

    Annual review of biochemistry

    2009  Volume 78, Page(s) 363–397

    Abstract: Deubiquitinating enzymes (DUBs) are proteases that process ubiquitin or ubiquitin-like gene products, reverse the modification of proteins by a single ubiquitin(-like) protein, and remodel polyubiquitin(-like) chains on target proteins. The human genome ... ...

    Abstract Deubiquitinating enzymes (DUBs) are proteases that process ubiquitin or ubiquitin-like gene products, reverse the modification of proteins by a single ubiquitin(-like) protein, and remodel polyubiquitin(-like) chains on target proteins. The human genome encodes nearly 100 DUBs with specificity for ubiquitin in five gene families. Most DUB activity is cryptic, and conformational rearrangements often occur during the binding of ubiquitin and/or scaffold proteins. DUBs with specificity for ubiquitin contain insertions and extensions modulating DUB substrate specificity, protein-protein interactions, and cellular localization. Binding partners and multiprotein complexes with which DUBs associate modulate DUB activity and substrate specificity. Quantitative studies of activity and protein-protein interactions, together with genetic studies and the advent of RNAi, have led to new insights into the function of yeast and human DUBs. This review discusses ubiquitin-specific DUBs, some of the generalizations emerging from recent studies of the regulation of DUB activity, and their roles in various cellular processes.
    MeSH term(s) Animals ; Endopeptidases/chemistry ; Endopeptidases/genetics ; Endopeptidases/metabolism ; Humans ; Protein Structure, Tertiary ; Ubiquitin/genetics ; Ubiquitin/metabolism ; Ubiquitination
    Chemical Substances Ubiquitin ; Endopeptidases (EC 3.4.-)
    Keywords covid19
    Language English
    Publishing date 2009-06-02
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 207924-0
    ISSN 1545-4509 ; 0066-4154
    ISSN (online) 1545-4509
    ISSN 0066-4154
    DOI 10.1146/annurev.biochem.78.082307.091526
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Defects in RNA quality control factors reveal RNAi-independent nucleation of heterochromatin.

    Reyes-Turcu, Francisca E / Zhang, Ke / Zofall, Martin / Chen, Eesin / Grewal, Shiv I S

    Nature structural & molecular biology

    2011  Volume 18, Issue 10, Page(s) 1132–1138

    Abstract: Heterochromatin assembly at Schizosaccharomyces pombe centromeres involves a self-reinforcing loop mechanism wherein chromatin-bound RNAi factors facilitate targeting of Clr4-Rik1 methyltransferase. However, the initial nucleation of heterochromatin has ... ...

    Abstract Heterochromatin assembly at Schizosaccharomyces pombe centromeres involves a self-reinforcing loop mechanism wherein chromatin-bound RNAi factors facilitate targeting of Clr4-Rik1 methyltransferase. However, the initial nucleation of heterochromatin has remained elusive. We show that cells lacking Mlo3, a protein involved in mRNP biogenesis and RNA quality control, assemble functional heterochromatin in RNAi-deficient cells. Heterochromatin restoration is linked to RNA surveillance because loss of Mlo3-associated TRAMP also rescues heterochromatin defects of RNAi mutants. mlo3Δ, which causes accumulation of bidirectional repeat-transcripts, restores Rik1 enrichment at repeats and triggers de novo heterochromatin formation in the absence of RNAi. RNAi-independent heterochromatin nucleation occurs at selected euchromatic loci that show upregulation of antisense RNAs in mlo3Δ cells. We find that the exosome RNA degradation machinery acts parallel to RNAi to promote heterochromatin formation at centromeres. These results suggest that RNAi-independent mechanisms exploit transcription and non-coding RNAs to nucleate heterochromatin.
    MeSH term(s) Centromere ; Heterochromatin/chemistry ; Heterochromatin/genetics ; Mutation ; Quality Control ; RNA Interference ; Schizosaccharomyces/genetics
    Chemical Substances Heterochromatin
    Language English
    Publishing date 2011-09-04
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Intramural
    ZDB-ID 2126708-X
    ISSN 1545-9985 ; 1545-9993
    ISSN (online) 1545-9985
    ISSN 1545-9993
    DOI 10.1038/nsmb.2122
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Recognition of Polyubiquitin Isoforms by the Multiple Ubiquitin Binding Modules of Isopeptidase T

    Reyes-Turcu, Francisca E / Shanks, John R / Komander, David / Wilkinson, Keith D

    Journal of biological chemistry. 2008 July 11, v. 283, no. 28

    2008  

    Abstract: The conjugation of polyubiquitin to target proteins acts as a signal that regulates target stability, localization, and function. Several ubiquitin binding domains have been described, and while much is known about ubiquitin binding to the isolated ... ...

    Abstract The conjugation of polyubiquitin to target proteins acts as a signal that regulates target stability, localization, and function. Several ubiquitin binding domains have been described, and while much is known about ubiquitin binding to the isolated domains, little is known with regard to how the domains interact with polyubiquitin in the context of full-length proteins. Isopeptidase T (IsoT/USP5) is a deubiquitinating enzyme that is largely responsible for the disassembly of unanchored polyubiquitin in the cell. IsoT has four ubiquitin binding domains: a zinc finger domain (ZnF UBP), which binds the proximal ubiquitin, a UBP domain that forms the active site, and two ubiquitin-associated (UBA) domains whose roles are unknown. Here, we show that the UBA domains are involved in binding two different polyubiquitin isoforms, linear and K48-linked. Using isothermal titration calorimetry, we show that IsoT has at least four ubiquitin binding sites for both polyubiquitin isoforms. The thermodynamics of the interactions reveal that the binding is enthalpy-driven. Mutation of the UBA domains suggests that UBA1 and UBA2 domains of IsoT interact with the third and fourth ubiquitins in both polyubiquitin isoforms, respectively. These data suggest that recognition of the polyubiquitin isoforms by IsoT involves considerable conformational mobility in the polyubiquitin ligand, in the enzyme, or in both.
    Language English
    Dates of publication 2008-0711
    Size p. 19581-19592.
    Publishing place American Society for Biochemistry and Molecular Biology
    Document type Article
    ZDB-ID 2997-x
    ISSN 1083-351X ; 0021-9258
    ISSN (online) 1083-351X
    ISSN 0021-9258
    Database NAL-Catalogue (AGRICOLA)

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  8. Article ; Online: RNAi triggered by specialized machinery silences developmental genes and retrotransposons.

    Yamanaka, Soichiro / Mehta, Sameet / Reyes-Turcu, Francisca E / Zhuang, Fanglei / Fuchs, Ryan T / Rong, Yikang / Robb, Gregory B / Grewal, Shiv I S

    Nature

    2012  Volume 493, Issue 7433, Page(s) 557–560

    Abstract: RNA interference (RNAi) is a conserved mechanism in which small interfering RNAs (siRNAs) guide the degradation of cognate RNAs, but also promote heterochromatin assembly at repetitive DNA elements such as centromeric repeats. However, the full extent of ...

    Abstract RNA interference (RNAi) is a conserved mechanism in which small interfering RNAs (siRNAs) guide the degradation of cognate RNAs, but also promote heterochromatin assembly at repetitive DNA elements such as centromeric repeats. However, the full extent of RNAi functions and its endogenous targets have not been explored. Here we show that, in the fission yeast Schizosaccharomyces pombe, RNAi and heterochromatin factors cooperate to silence diverse loci, including sexual differentiation genes, genes encoding transmembrane proteins, and retrotransposons that are also targeted by the exosome RNA degradation machinery. In the absence of the exosome, transcripts are processed preferentially by the RNAi machinery, revealing siRNA clusters and a corresponding increase in heterochromatin modifications across large domains containing genes and retrotransposons. We show that the generation of siRNAs and heterochromatin assembly by RNAi is triggered by a mechanism involving the canonical poly(A) polymerase Pla1 and an associated RNA surveillance factor Red1, which also activate the exosome. Notably, siRNA production and heterochromatin modifications at these target loci are regulated by environmental growth conditions, and by developmental signals that induce gene expression during sexual differentiation. Our analyses uncover an interaction between RNAi and the exosome that is conserved in Drosophila, and show that differentiation signals modulate RNAi silencing to regulate developmental genes.
    MeSH term(s) Animals ; Drosophila melanogaster/genetics ; Exome/genetics ; Gene Expression Regulation, Fungal/genetics ; Genes, Fungal/genetics ; Heterochromatin/genetics ; Multigene Family/genetics ; Polynucleotide Adenylyltransferase/genetics ; RNA Interference ; RNA Stability/genetics ; RNA, Fungal/genetics ; RNA, Small Interfering/genetics ; Retroelements/genetics ; Schizosaccharomyces/cytology ; Schizosaccharomyces/enzymology ; Schizosaccharomyces/genetics ; Schizosaccharomyces/growth & development ; Schizosaccharomyces pombe Proteins/genetics ; Schizosaccharomyces pombe Proteins/metabolism ; Sex Differentiation/genetics
    Chemical Substances Heterochromatin ; RNA, Fungal ; RNA, Small Interfering ; Retroelements ; Schizosaccharomyces pombe Proteins ; Polynucleotide Adenylyltransferase (EC 2.7.7.19)
    Language English
    Publishing date 2012-11-14
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Intramural
    ZDB-ID 120714-3
    ISSN 1476-4687 ; 0028-0836
    ISSN (online) 1476-4687
    ISSN 0028-0836
    DOI 10.1038/nature11716
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: Recognition of polyubiquitin isoforms by the multiple ubiquitin binding modules of isopeptidase T.

    Reyes-Turcu, Francisca E / Shanks, John R / Komander, David / Wilkinson, Keith D

    The Journal of biological chemistry

    2008  Volume 283, Issue 28, Page(s) 19581–19592

    Abstract: The conjugation of polyubiquitin to target proteins acts as a signal that regulates target stability, localization, and function. Several ubiquitin binding domains have been described, and while much is known about ubiquitin binding to the isolated ... ...

    Abstract The conjugation of polyubiquitin to target proteins acts as a signal that regulates target stability, localization, and function. Several ubiquitin binding domains have been described, and while much is known about ubiquitin binding to the isolated domains, little is known with regard to how the domains interact with polyubiquitin in the context of full-length proteins. Isopeptidase T (IsoT/USP5) is a deubiquitinating enzyme that is largely responsible for the disassembly of unanchored polyubiquitin in the cell. IsoT has four ubiquitin binding domains: a zinc finger domain (ZnF UBP), which binds the proximal ubiquitin, a UBP domain that forms the active site, and two ubiquitin-associated (UBA) domains whose roles are unknown. Here, we show that the UBA domains are involved in binding two different polyubiquitin isoforms, linear and K48-linked. Using isothermal titration calorimetry, we show that IsoT has at least four ubiquitin binding sites for both polyubiquitin isoforms. The thermodynamics of the interactions reveal that the binding is enthalpy-driven. Mutation of the UBA domains suggests that UBA1 and UBA2 domains of IsoT interact with the third and fourth ubiquitins in both polyubiquitin isoforms, respectively. These data suggest that recognition of the polyubiquitin isoforms by IsoT involves considerable conformational mobility in the polyubiquitin ligand, in the enzyme, or in both.
    MeSH term(s) Animals ; Binding Sites/physiology ; Endopeptidases/chemistry ; Endopeptidases/genetics ; Endopeptidases/metabolism ; Humans ; Mutation ; Protein Binding/physiology ; Protein Isoforms/chemistry ; Protein Isoforms/genetics ; Protein Isoforms/metabolism ; Protein Structure, Tertiary/physiology ; Recombinant Fusion Proteins/chemistry ; Recombinant Fusion Proteins/genetics ; Recombinant Fusion Proteins/metabolism ; Ubiquitin/chemistry ; Ubiquitin/genetics ; Ubiquitin/metabolism ; Ubiquitination/physiology ; Zinc Fingers/physiology
    Chemical Substances Protein Isoforms ; Recombinant Fusion Proteins ; Ubiquitin ; Endopeptidases (EC 3.4.-) ; ubiquitin isopeptidase (EC 3.4.99.-)
    Language English
    Publishing date 2008-05-15
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 2997-x
    ISSN 1083-351X ; 0021-9258
    ISSN (online) 1083-351X
    ISSN 0021-9258
    DOI 10.1074/jbc.M800947200
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: RNA elimination machinery targeting meiotic mRNAs promotes facultative heterochromatin formation.

    Zofall, Martin / Yamanaka, Soichiro / Reyes-Turcu, Francisca E / Zhang, Ke / Rubin, Chanan / Grewal, Shiv I S

    Science (New York, N.Y.)

    2011  Volume 335, Issue 6064, Page(s) 96–100

    Abstract: Facultative heterochromatin that changes during cellular differentiation coordinates regulated gene expression, but its assembly is poorly understood. Here, we describe facultative heterochromatin islands in fission yeast and show that their formation at ...

    Abstract Facultative heterochromatin that changes during cellular differentiation coordinates regulated gene expression, but its assembly is poorly understood. Here, we describe facultative heterochromatin islands in fission yeast and show that their formation at meiotic genes requires factors that eliminate meiotic messenger RNAs (mRNAs) during vegetative growth. Blocking production of meiotic mRNA or loss of RNA elimination factors, including Mmi1 and Red1 proteins, abolishes heterochromatin islands. RNA elimination machinery is enriched at meiotic loci and interacts with Clr4/SUV39h, a methyltransferase involved in heterochromatin assembly. Heterochromatin islands disassemble in response to nutritional signals that induce sexual differentiation. This process involves the antisilencing factor Epe1, the loss of which causes dramatic increase in heterochromatic loci. Our analyses uncover unexpected regulatory roles for mRNA-processing factors that assemble dynamic heterochromatin to modulate gene expression.
    MeSH term(s) Cell Cycle Proteins/metabolism ; Chromatin Assembly and Disassembly ; Chromatin Immunoprecipitation ; Dynactin Complex ; Gene Expression Regulation, Fungal ; Genes, Fungal ; Heterochromatin/metabolism ; Histone-Lysine N-Methyltransferase ; Histones/metabolism ; Meiosis/genetics ; Methyltransferases/metabolism ; Microtubule Proteins/genetics ; Microtubule Proteins/metabolism ; Nitrogen/metabolism ; Nuclear Proteins/genetics ; Nuclear Proteins/metabolism ; RNA Interference ; RNA, Fungal/genetics ; RNA, Fungal/metabolism ; RNA, Messenger/genetics ; RNA, Messenger/metabolism ; Schizosaccharomyces/genetics ; Schizosaccharomyces/growth & development ; Schizosaccharomyces/metabolism ; Schizosaccharomyces pombe Proteins/genetics ; Schizosaccharomyces pombe Proteins/metabolism ; mRNA Cleavage and Polyadenylation Factors/metabolism
    Chemical Substances Cell Cycle Proteins ; Dynactin Complex ; Heterochromatin ; Histones ; Microtubule Proteins ; Mmi1 protein, S pombe ; Nuclear Proteins ; RNA, Fungal ; RNA, Messenger ; Schizosaccharomyces pombe Proteins ; Ssm4 protein, S pombe ; epe1 protein, S pombe ; mRNA Cleavage and Polyadenylation Factors ; mei4 protein, S pombe ; Methyltransferases (EC 2.1.1.-) ; Histone-Lysine N-Methyltransferase (EC 2.1.1.43) ; clr4 protein, S pombe (EC 2.1.1.43) ; Nitrogen (N762921K75)
    Language English
    Publishing date 2011-12-01
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Intramural
    ZDB-ID 128410-1
    ISSN 1095-9203 ; 0036-8075
    ISSN (online) 1095-9203
    ISSN 0036-8075
    DOI 10.1126/science.1211651
    Database MEDical Literature Analysis and Retrieval System OnLINE

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