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  1. Article ; Online: The allosteric activation of cGAS underpins its dynamic signaling landscape.

    Hooy, Richard M / Sohn, Jungsan

    eLife

    2018  Volume 7

    Abstract: Cyclic G/AMP synthase (cGAS) initiates type-1 interferon responses against cytosolic double-stranded (ds)DNA, which range from antiviral gene expression to apoptosis. The mechanism by which cGAS shapes this diverse signaling landscape remains poorly ... ...

    Abstract Cyclic G/AMP synthase (cGAS) initiates type-1 interferon responses against cytosolic double-stranded (ds)DNA, which range from antiviral gene expression to apoptosis. The mechanism by which cGAS shapes this diverse signaling landscape remains poorly defined. We find that substrate-binding and dsDNA length-dependent binding are coupled to the intrinsic dimerization equilibrium of cGAS, with its N-terminal domain potentiating dimerization. Notably, increasing the dimeric fraction by raising cGAS and substrate concentrations diminishes duplex length-dependent activation, but does not negate the requirement for dsDNA. These results demonstrate that reaction context dictates the duplex length dependence, reconciling competing claims on the role of dsDNA length in cGAS activation. Overall, our study reveals how ligand-mediated allostery positions cGAS in standby, ready to tune its signaling pathway in a switch-like fashion.
    MeSH term(s) Allosteric Regulation ; Biophysical Phenomena ; DNA/metabolism ; Humans ; Kinetics ; Nucleotidyltransferases/chemistry ; Nucleotidyltransferases/metabolism ; Protein Domains ; Protein Multimerization ; Signal Transduction ; Substrate Specificity
    Chemical Substances DNA (9007-49-2) ; Nucleotidyltransferases (EC 2.7.7.-) ; cGAS protein, human (EC 2.7.7.-)
    Language English
    Publishing date 2018-10-08
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 2687154-3
    ISSN 2050-084X ; 2050-084X
    ISSN (online) 2050-084X
    ISSN 2050-084X
    DOI 10.7554/eLife.39984
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Self-assembly and structure of a clathrin-independent AP-1:Arf1 tubular membrane coat.

    Hooy, Richard M / Iwamoto, Yuichiro / Tudorica, Dan A / Ren, Xuefeng / Hurley, James H

    Science advances

    2022  Volume 8, Issue 42, Page(s) eadd3914

    Abstract: The adaptor protein (AP) complexes not only form the inner layer of clathrin coats but also have clathrin-independent roles in membrane traffic whose mechanisms are unknown. HIV-1 Nef hijacks AP-1 to sequester major histocompatibility complex class I ( ... ...

    Abstract The adaptor protein (AP) complexes not only form the inner layer of clathrin coats but also have clathrin-independent roles in membrane traffic whose mechanisms are unknown. HIV-1 Nef hijacks AP-1 to sequester major histocompatibility complex class I (MHC-I), evading immune detection. We found that AP-1:Arf1:Nef:MHC-I forms a coat on tubulated membranes without clathrin and determined its structure. The coat assembles via Arf1 dimer interfaces. AP-1-positive tubules are enriched in cells upon clathrin knockdown. Nef localizes preferentially to AP-1 tubules in cells, explaining how Nef sequesters MHC-I. Coat contact residues are conserved across Arf isoforms and the Arf-dependent AP complexes AP-1, AP-3, and AP-4. Thus, AP complexes can self-assemble with Arf1 into tubular coats without clathrin or other scaffolding factors. The AP-1:Arf1 coat defines the structural basis of a broader class of tubulovesicular membrane coats as an intermediate in clathrin vesicle formation from internal membranes and as an MHC-I sequestration mechanism in HIV-1 infection.
    Language English
    Publishing date 2022-10-21
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2810933-8
    ISSN 2375-2548 ; 2375-2548
    ISSN (online) 2375-2548
    ISSN 2375-2548
    DOI 10.1126/sciadv.add3914
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Structure of SARS-CoV-2 ORF8, a rapidly evolving immune evasion protein.

    Flower, Thomas G / Buffalo, Cosmo Z / Hooy, Richard M / Allaire, Marc / Ren, Xuefeng / Hurley, James H

    Proceedings of the National Academy of Sciences of the United States of America

    2021  Volume 118, Issue 2

    Abstract: The molecular basis for the severity and rapid spread of the COVID-19 disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is largely unknown. ORF8 is a rapidly evolving accessory protein that has been proposed to interfere with ...

    Abstract The molecular basis for the severity and rapid spread of the COVID-19 disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is largely unknown. ORF8 is a rapidly evolving accessory protein that has been proposed to interfere with immune responses. The crystal structure of SARS-CoV-2 ORF8 was determined at 2.04-Å resolution by X-ray crystallography. The structure reveals a ∼60-residue core similar to SARS-CoV-2 ORF7a, with the addition of two dimerization interfaces unique to SARS-CoV-2 ORF8. A covalent disulfide-linked dimer is formed through an N-terminal sequence specific to SARS-CoV-2, while a separate noncovalent interface is formed by another SARS-CoV-2-specific sequence,
    MeSH term(s) Evolution, Molecular ; Immune Evasion ; Molecular Structure ; SARS-CoV-2/chemistry ; Viral Proteins/chemistry
    Chemical Substances ORF8 protein, SARS-CoV-2 ; Viral Proteins
    Language English
    Publishing date 2021-04-08
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.2021785118
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  4. Article: Structure of SARS-CoV-2 ORF8, a rapidly evolving coronavirus protein implicated in immune evasion.

    Flower, Thomas G / Buffalo, Cosmo Z / Hooy, Richard M / Allaire, Marc / Ren, Xuefeng / Hurley, James H

    bioRxiv : the preprint server for biology

    2020  

    Abstract: The molecular basis for the severity and rapid spread of the COVID-19 disease caused by SARS-CoV-2 is largely unknown. ORF8 is a rapidly evolving accessory protein that has been proposed to interfere with immune responses. The crystal structure of SARS- ... ...

    Abstract The molecular basis for the severity and rapid spread of the COVID-19 disease caused by SARS-CoV-2 is largely unknown. ORF8 is a rapidly evolving accessory protein that has been proposed to interfere with immune responses. The crystal structure of SARS-CoV-2 ORF8 was determined at 2.04 Å resolution by x-ray crystallography. The structure reveals a ~60 residue core similar to SARS-CoV ORF7a with the addition of two dimerization interfaces unique to SARS-CoV-2 ORF8. A covalent disulfide-linked dimer is formed through an N-terminal sequence specific to SARS-CoV-2, while a separate non-covalent interface is formed by another SARS-CoV-2-specific sequence,
    Keywords covid19
    Language English
    Publishing date 2020-08-27
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2020.08.27.270637
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Allosteric coupling between Mn2+ and dsDNA controls the catalytic efficiency and fidelity of cGAS.

    Hooy, Richard M / Massaccesi, Guido / Rousseau, Kimberly E / Chattergoon, Michael A / Sohn, Jungsan

    Nucleic acids research

    2020  Volume 48, Issue 8, Page(s) 4435–4447

    Abstract: Cyclic-G/AMP (cGAMP) synthase (cGAS) triggers host innate immune responses against cytosolic double-stranded (ds)DNA arising from genotoxic stress and pathogen invasion. The canonical activation mechanism of cGAS entails dsDNA-binding and dimerization. ... ...

    Abstract Cyclic-G/AMP (cGAMP) synthase (cGAS) triggers host innate immune responses against cytosolic double-stranded (ds)DNA arising from genotoxic stress and pathogen invasion. The canonical activation mechanism of cGAS entails dsDNA-binding and dimerization. Here, we report an unexpected activation mechanism of cGAS in which Mn2+ activates monomeric cGAS without dsDNA. Importantly, the Mn2+-mediated activation positively couples with dsDNA-dependent activation in a concerted manner. Moreover, the positive coupling between Mn2+ and dsDNA length-dependent activation requires the cognate ATP/GTP substrate pair, while negative-cooperativity suppresses Mn2+ utilization by either ATP or GTP alone. Additionally, while Mn2+ accelerates the overall catalytic activity, dsDNA length-dependent dimerization specifically accelerates the cyclization of cGAMP. Together, we demonstrate how the intrinsic allostery of cGAS efficiently yet precisely tunes its activity.
    MeSH term(s) Adenosine Triphosphate/metabolism ; Allosteric Regulation ; Biocatalysis ; Cell Line ; DNA/chemistry ; DNA/metabolism ; Enzyme Activation ; Humans ; Manganese ; Nucleotidyltransferases/chemistry ; Nucleotidyltransferases/metabolism ; Substrate Specificity
    Chemical Substances Manganese (42Z2K6ZL8P) ; Adenosine Triphosphate (8L70Q75FXE) ; DNA (9007-49-2) ; Nucleotidyltransferases (EC 2.7.7.-) ; cGAS protein, human (EC 2.7.7.-)
    Language English
    Publishing date 2020-03-12
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 186809-3
    ISSN 1362-4962 ; 1362-4954 ; 0301-5610 ; 0305-1048
    ISSN (online) 1362-4962 ; 1362-4954
    ISSN 0301-5610 ; 0305-1048
    DOI 10.1093/nar/gkaa084
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Structure of SARS-CoV-2 ORF8, a rapidly evolving coronavirus protein implicated in immune evasion

    Flower, Thomas G / Buffalo, Cosmo Z / Hooy, Richard M / Allaire, Marc / Ren, Xuefeng / Hurley, James H

    bioRxiv

    Abstract: The molecular basis for the severity and rapid spread of the COVID-19 disease caused by SARS-CoV-2 is largely unknown. ORF8 is a rapidly evolving accessory protein that has been proposed to interfere with immune responses. The crystal structure of SARS- ... ...

    Abstract The molecular basis for the severity and rapid spread of the COVID-19 disease caused by SARS-CoV-2 is largely unknown. ORF8 is a rapidly evolving accessory protein that has been proposed to interfere with immune responses. The crystal structure of SARS-CoV-2 ORF8 was determined at 2.04 Angstrom resolution by x-ray crystallography. The structure reveals a ~60 residue core similar to SARS-CoV ORF7a with the addition of two dimerization interfaces unique to SARS-CoV-2 ORF8. A covalent disulfide-linked dimer is formed through an N-terminal sequence specific to SARS-CoV-2, while a separate non-covalent interface is formed by another SARS-CoV-2-specific sequence, 73YIDI76. Together the presence of these interfaces shows how SARS-CoV-2 ORF8 can form unique large-scale assemblies not possible for SARS-CoV, potentially mediating unique immune suppression and evasion activities.
    Keywords covid19
    Language English
    Publishing date 2020-08-27
    Publisher Cold Spring Harbor Laboratory
    Document type Article ; Online
    DOI 10.1101/2020.08.27.270637
    Database COVID19

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  7. Article ; Online: Chromatin-bound cGAS is an inhibitor of DNA repair and hence accelerates genome destabilization and cell death.

    Jiang, Hui / Xue, Xiaoyu / Panda, Swarupa / Kawale, Ajinkya / Hooy, Richard M / Liang, Fengshan / Sohn, Jungsan / Sung, Patrick / Gekara, Nelson O

    The EMBO journal

    2019  Volume 38, Issue 21, Page(s) e102718

    Abstract: DNA repair via homologous recombination (HR) is indispensable for genome integrity and cell survival but if unrestrained can result in undesired chromosomal rearrangements. The regulatory mechanisms of HR are not fully understood. Cyclic GMP-AMP synthase ...

    Abstract DNA repair via homologous recombination (HR) is indispensable for genome integrity and cell survival but if unrestrained can result in undesired chromosomal rearrangements. The regulatory mechanisms of HR are not fully understood. Cyclic GMP-AMP synthase (cGAS) is best known as a cytosolic innate immune sensor critical for the outcome of infections, inflammatory diseases, and cancer. Here, we report that cGAS is primarily a chromatin-bound protein that inhibits DNA repair by HR, thereby accelerating genome destabilization, micronucleus generation, and cell death under conditions of genomic stress. This function is independent of the canonical STING-dependent innate immune activation and is physiologically relevant for irradiation-induced depletion of bone marrow cells in mice. Mechanistically, we demonstrate that inhibition of HR repair by cGAS is linked to its ability to self-oligomerize, causing compaction of bound template dsDNA into a higher-ordered state less amenable to strand invasion by RAD51-coated ssDNA filaments. This previously unknown role of cGAS has implications for understanding its involvement in genome instability-associated disorders including cancer.
    MeSH term(s) Animals ; Cell Death ; Cell Nucleus/genetics ; Cell Nucleus/metabolism ; Chromatin/genetics ; Chromatin/metabolism ; DNA Damage ; Genomic Instability ; HEK293 Cells ; HeLa Cells ; Humans ; Membrane Proteins/genetics ; Membrane Proteins/metabolism ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Nucleotidyltransferases/genetics ; Nucleotidyltransferases/metabolism ; Nucleotidyltransferases/physiology ; Recombinational DNA Repair ; Signal Transduction
    Chemical Substances Chromatin ; Membrane Proteins ; STING1 protein, human ; Nucleotidyltransferases (EC 2.7.7.-) ; cGAS protein, human (EC 2.7.7.-) ; cGAS protein, mouse (EC 2.7.7.-)
    Language English
    Publishing date 2019-09-23
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 586044-1
    ISSN 1460-2075 ; 0261-4189
    ISSN (online) 1460-2075
    ISSN 0261-4189
    DOI 10.15252/embj.2019102718
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  8. Article ; Online: The scope of phage display for membrane proteins.

    Vithayathil, Rosemarie / Hooy, Richard M / Cocco, Melanie J / Weiss, Gregory A

    Journal of molecular biology

    2011  Volume 414, Issue 4, Page(s) 499–510

    Abstract: Numerous examples of phage display applied to soluble proteins demonstrate the power of the technique for protein engineering, affinity reagent discovery and structure-function studies. Recent reports have expanded phage display to include membrane ... ...

    Abstract Numerous examples of phage display applied to soluble proteins demonstrate the power of the technique for protein engineering, affinity reagent discovery and structure-function studies. Recent reports have expanded phage display to include membrane proteins (MPs). The scope and limitations of MP display remain undefined. Therefore, we report data from the phage display of representative types of membrane-associated proteins including plasma, nuclear, peripheral, single and multipass. The peripheral MP neuromodulin displays robustly with packaging by conventional M13-KO7 helper phage. The monotopic MP Nogo-66 can also display on the phage surface, if packaged by the modified M13-KO7(+) helper phage. The modified phage coat of KO7(+) can better mimic the zwitterionic character of the plasma membrane. Four examples of putatively α-helical, integral MPs failed to express as fusions to an anchoring phage coat protein and therefore did not display on the phage surface. However, the β-barrel MPs ShuA (Shigella heme uptake A) and MOMP (major outer membrane protein), which pass through the membrane 22 and 16 times, respectively, can display surprisingly well on the surfaces of both conventional and KO7(+) phages. The results provide a guide for protein engineering and large-scale mutagenesis enabled by the phage display of MPs.
    MeSH term(s) Bacteriophage M13/genetics ; Capsid Proteins/genetics ; Capsid Proteins/metabolism ; Cloning, Molecular/methods ; Genetic Techniques ; Membrane Proteins/genetics ; Membrane Proteins/metabolism ; Models, Molecular ; Mutagenesis/genetics ; Peptide Library ; Protein Engineering/methods ; Protein Structure, Secondary/genetics
    Chemical Substances Capsid Proteins ; Membrane Proteins ; Peptide Library ; coat protein, Bacteriophage M13
    Language English
    Publishing date 2011-10-20
    Publishing country Netherlands
    Document type Journal Article ; Research Support, N.I.H., Extramural ; 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.2011.10.021
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  9. Article ; Online: Tyrosine phosphorylation of mig6 reduces its inhibition of the epidermal growth factor receptor.

    Wang, Zhihong / Raines, Lily L / Hooy, Richard M / Roberson, Heather / Leahy, Daniel J / Cole, Philip A

    ACS chemical biology

    2013  Volume 8, Issue 11, Page(s) 2372–2376

    Abstract: Under physiological conditions, epidermal growth factor receptor (EGFR) tyrosine kinase activity is tightly controlled through the coordinated action of both positive and negative regulators. Aberrant EGFR activation occurs frequently in many cancer ... ...

    Abstract Under physiological conditions, epidermal growth factor receptor (EGFR) tyrosine kinase activity is tightly controlled through the coordinated action of both positive and negative regulators. Aberrant EGFR activation occurs frequently in many cancer types, and the endogenous EGFR feedback inhibitor, Mig6/RALT, is more efficiently phosphorylated by oncogenic EGFR variants. We have utilized expressed protein ligation to generate semisynthetic Tyr394 phosphorylated and unphosphorylated forms of the Mig6 protein and shown that phosphorylation of Mig6 reduces its ability to inhibit purified, near full-length EGFR (tEGFR). We also demonstrate that the kinetic parameters of tEGFR are similar whether solubilized in detergent or reconstitutued in nanodisc bilayers. These findings suggest a mechanism by which EGFR and its family members evade negative regulation by Mig6 under pathological conditions.
    MeSH term(s) Adaptor Proteins, Signal Transducing/chemistry ; Adaptor Proteins, Signal Transducing/metabolism ; Adaptor Proteins, Signal Transducing/pharmacology ; Amino Acid Sequence ; Biological Assay ; ErbB Receptors/antagonists & inhibitors ; Humans ; Models, Biological ; Mutation ; Phosphorylation ; Tumor Suppressor Proteins/chemistry ; Tumor Suppressor Proteins/metabolism ; Tumor Suppressor Proteins/pharmacology ; Tyrosine/metabolism
    Chemical Substances Adaptor Proteins, Signal Transducing ; ERRFI1 protein, human ; Tumor Suppressor Proteins ; Tyrosine (42HK56048U) ; ErbB Receptors (EC 2.7.10.1)
    Language English
    Publishing date 2013-09-06
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ISSN 1554-8937
    ISSN (online) 1554-8937
    DOI 10.1021/cb4005707
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  10. Article ; Online: Cooperative assembly of IFI16 filaments on dsDNA provides insights into host defense strategy.

    Morrone, Seamus R / Wang, Tao / Constantoulakis, Leeza M / Hooy, Richard M / Delannoy, Michael J / Sohn, Jungsan

    Proceedings of the National Academy of Sciences of the United States of America

    2013  Volume 111, Issue 1, Page(s) E62–71

    Abstract: Whether host DNA receptors have any capacity to distinguish self from nonself at the molecular level is an outstanding question in the innate immunity of mammals. Here, by using quantitative assays and electron microscopy, we show that cooperatively ... ...

    Abstract Whether host DNA receptors have any capacity to distinguish self from nonself at the molecular level is an outstanding question in the innate immunity of mammals. Here, by using quantitative assays and electron microscopy, we show that cooperatively assembling into filaments on dsDNA may serve as an integral mechanism by which human IFN-inducible protein-16 (IFI16) engages foreign DNA. IFI16 is essential for defense against a number of different pathogens, and its aberrant activity is also implicated in several autoimmune disorders, such as Sjögren syndrome. IFI16 cooperatively binds dsDNA in a length-dependent manner and clusters into distinct protein filaments even in the presence of excess dsDNA. Consequently, the assembled IFI16⋅dsDNA oligomers are clearly different from the conventional noninteracting entities resembling beads on a string. The isolated DNA-binding domains of IFI16 engage dsDNA without forming filaments and with weak affinity, and it is the non-DNA-binding pyrin domain of IFI16 that drives the cooperative filament assembly. The surface residues on the pyrin domain that mediate the cooperative DNA binding are conserved, suggesting that related receptors use a common mechanism. These results suggest that IFI16 clusters into signaling foci in a switch-like manner and that it is capable of using the size of naked dsDNA as a molecular ruler to distinguish self from nonself.
    MeSH term(s) Amino Acid Sequence ; Binding, Competitive ; Cell Nucleus/metabolism ; Cross-Linking Reagents/chemistry ; DNA/chemistry ; Humans ; Immunity, Innate ; Inflammation ; Microscopy, Electron ; Molecular Sequence Data ; Nuclear Proteins/chemistry ; Phosphoproteins/chemistry ; Protein Binding ; Protein Structure, Tertiary ; Signal Transduction
    Chemical Substances Cross-Linking Reagents ; Nuclear Proteins ; Phosphoproteins ; IFI16 protein, human (148998-64-5) ; DNA (9007-49-2)
    Language English
    Publishing date 2013-12-23
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.1313577111
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