PAR recognition by multiple reader domains of PARP1 allosterically regulates the DNA-dependent activities and independently stimulates the catalytic activity of PARP1

Poly(ADP-ribosyl)ation is a post translational modification, predominantly catalyzed by Poly(ADP-ribose) polymerase 1 (PARP1) in response to DNA damage, mediating the DNA repair process to maintain genomic integrity. Single strand (SSB) and double strand (DSB) DNA breaks are bonafide stimulators of PARP1 activity. We identified that, in addition, single strand (ss) DNA also binds and stimulates the PARP1 activity. Poly(ADP-ribose) (PAR) is chemically similar to ssDNA. However, PAR mediated PARP1 regulation remains unexplored. Here, we report ZnF3, BRCT and WGR, hitherto uncharacterized, as PAR-specific reader domains of PARP1. Surprisingly, these domains recognize PARylated protein with a higher affinity compared to PAR, but do not bind to DNA. Conversely, N-terminal domains, ZnF1 and ZnF2, of PARP1 recognize DNA but not PAR. Further competition binding studies suggest that PAR binding, allosterically releases DNA from PARP1. Unexpectedly, PAR showed catalytic stimulation of PARP1 but hampers the DNA dependent stimulation. Altogether, our work discovers dedicated PAR and DNA reader domains of the PARP1, and uncovers a novel mechanism of allosteric stimulation of the catalytic activity of PARP1 but retardation of DNA-dependent activities of PARP1 by its catalytic product PAR.

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Poly(ADP-ribose) glycohydrolase promotes formation and homology-directed repair of meiotic DNA double-strand breaks independent of its catalytic activity

10.1101/2020.03.12.988840 ◽

2020 ◽

Cited By ~ 2

Author(s):

Eva Janisiw ◽

Marilina Raices ◽

Fabiola Balmir ◽

Luis Paulin Paz ◽

Antoine Baudrimont ◽

...

Keyword(s):

Catalytic Activity ◽

Synaptonemal Complex ◽

Double Strand Breaks ◽

Dna Double Strand Breaks ◽

Post Translational Modification ◽

Dna Breaks ◽

Strand Breaks ◽

Homology Directed Repair ◽

Damage Repair ◽

Somatic Tissues

SummaryPoly(ADP-ribosyl)ation is a reversible post-translational modification synthetized by ADP-ribose transferases and removed by poly(ADP-ribose) glycohydrolase (PARG), which plays important roles in DNA damage repair. While well-studied in somatic tissues, much less is known about poly(ADP-ribosyl)ation in the germline, where DNA double-strand breaks are introduced by a regulated program and repaired by crossover recombination to establish a tether between homologous chromosomes. The interaction between the parental chromosomes is facilitated by meiotic specific adaptation of the chromosome axes and cohesins, and reinforced by the synaptonemal complex. Here, we uncover an unexpected role for PARG in promoting the induction of meiotic DNA breaks and their homologous recombination-mediated repair in Caenorhabditis elegans. PARG-1/PARG interacts with both axial and central elements of the synaptonemal complex, REC-8/Rec8 and the MRN/X complex. PARG-1 shapes the recombination landscape and reinforces the tightly regulated control of crossover numbers without requiring its catalytic activity. We unravel roles in regulating meiosis, beyond its enzymatic activity in poly(ADP-ribose) catabolism.

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Adenosine-receptor-mediated stimulation of low-Km GTPase in guinea-pig cerebral cortex

Biochemical Journal ◽

10.1042/bj2320501 ◽

1985 ◽

Vol 232 (2) ◽

pp. 501-504 ◽

Cited By ~ 9

Author(s):

V Hausleithner ◽

M Freissmuth ◽

W Schütz

Keyword(s):

Adenylate Cyclase ◽

Guinea Pig ◽

Radioligand Binding ◽

Rank Order ◽

Binding Studies ◽

Gtp Hydrolysis ◽

Sequence Of Events ◽

Competition Binding ◽

Cortical Membranes ◽

Stimulation Of

Inhibition of receptor-coupled adenylate cyclase by hormones is proposed to be associated with GTP hydrolysis. Since adenosine inhibits cerebral-cortical adenylate cyclase via A1 adenosine receptors, the present study attempts to verify this mechanism for A1-selective adenosine derivatives. In guinea-pig cortical membranes N6-(phenylisopropyl)adenosine (PIA) increased the Vmax. of the low-Km GTPase, with an EC50 (concentration causing 50% of maximal stimulation) of about 0.1 microM, and the stimulatory effect was competitively antagonized by 5 microM-8-phenyltheophylline. The rank order of potency of the stereoisomers of PIA and of 5-(N-ethylcarboxamido)adenosine (NECA) to stimulate GTPase correlated with their ability to inhibit adenylate cyclase activity (R-PIA greater than NECA greater than S-PIA). Competition binding studies with (-)-N6- ([125I]iodo-4-hydroxyphenylisopropyl)adenosine suggest that adenylyl imidodiphosphate (p[NH]ppA), an essential component of the GTPase assay system, is a more potent A1-receptor agonist than ATP, with an IC50 (concentration giving half-maximal displacement of radioligand binding) of 7.9 microM. On the basis of the p[NH]ppA concentration used in the GTPase assay (1.25 mM), enzyme stimulation by adenosine seems to be highly underestimated. Nevertheless, adenosine-induced GTP hydrolysis reflects an increased turnover of guanine nucleotides at the Ni regulatory site and appears to be a crucial step in the sequence of events processing the inhibitory signal to adenylate cyclase.

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Poly(ADP-ribose) glycohydrolase coordinates meiotic DNA double-strand break induction and repair independent of its catalytic activity

Nature Communications ◽

10.1038/s41467-020-18693-1 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Eva Janisiw ◽

Marilina Raices ◽

Fabiola Balmir ◽

Luis F. Paulin ◽

Antoine Baudrimont ◽

...

Keyword(s):

Catalytic Activity ◽

Synaptonemal Complex ◽

Strand Break ◽

Dna Double Strand Breaks ◽

Post Translational Modification ◽

Dna Breaks ◽

Strand Breaks ◽

Damage Repair ◽

Dna Double Strand Break ◽

Somatic Tissues

Abstract Poly(ADP-ribosyl)ation is a reversible post-translational modification synthetized by ADP-ribose transferases and removed by poly(ADP-ribose) glycohydrolase (PARG), which plays important roles in DNA damage repair. While well-studied in somatic tissues, much less is known about poly(ADP-ribosyl)ation in the germline, where DNA double-strand breaks are introduced by a regulated program and repaired by crossover recombination to establish a tether between homologous chromosomes. The interaction between the parental chromosomes is facilitated by meiotic specific adaptation of the chromosome axes and cohesins, and reinforced by the synaptonemal complex. Here, we uncover an unexpected role for PARG in coordinating the induction of meiotic DNA breaks and their homologous recombination-mediated repair in Caenorhabditis elegans. PARG-1/PARG interacts with both axial and central elements of the synaptonemal complex, REC-8/Rec8 and the MRN/X complex. PARG-1 shapes the recombination landscape and reinforces the tightly regulated control of crossover numbers without requiring its catalytic activity. We unravel roles in regulating meiosis, beyond its enzymatic activity in poly(ADP-ribose) catabolism.

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Magnesium stimulation of catalytic activity of horse liver aldehyde dehydrogenase. Changes in molecular weight and catalytic sites.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)70631-0 ◽

1980 ◽

Vol 255 (17) ◽

pp. 8206-8209

Author(s):

K. Takahashi ◽

H. Weiner

Keyword(s):

Molecular Weight ◽

Catalytic Activity ◽

Aldehyde Dehydrogenase ◽

Horse Liver ◽

Catalytic Sites ◽

Liver Aldehyde Dehydrogenase ◽

Stimulation Of

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The binding of human complement proteins C5, factor B, β1H and properdin to complement fragment C3b on zymosan

Biochemical Journal ◽

10.1042/bj1990485 ◽

1981 ◽

Vol 199 (3) ◽

pp. 485-496 ◽

Cited By ~ 82

Author(s):

R G DiScipio

Keyword(s):

Protein Modification ◽

Alternative Pathway ◽

Covalent Binding ◽

Association Constants ◽

Affinity Constant ◽

Distinct Region ◽

Binding Studies ◽

Factor B ◽

Complement Proteins ◽

Competition Binding

The covalent binding of complement fragment C3b to zymosan by the action of the alternative-pathway C3 convertase and the reversible binding of several complement proteins (component C5, factor B, beta 1H and properdin) to C3b on zymosan have been investigated. When C3b is deposited on zymosan after activation by a surface-bound C3 convertase, the C3b molecules are deposited in foci around the C3 convertase site, with an average of 30 C3b molecules per site. The association constants of C5, factor B, beta 1H, and properdin for C3b bound to zymosan have been determined. The association constants ranged from 6.5 x 10(-5) M-1 for factor B to 2.9 x 10(7) M-1 for properdin. An approximate stoichiometry of 1 : 1 for C5, factor B, and properdin binding to C3b has been observed. Curvilinear Scatchard plots were observed for beta 1H binding to C3b, with the maximal extrapolated ratio of beta 1H to C3b of 0.32. Physiological amounts of properdin increase by 7-fold the affinity constant for factor B binding to C3b with no alteration in the stoichiometry. Similarly, physiological amounts of factor B increase the affinity constant of properdin to C3b about 4-fold with only a small measured difference in stoichiometry. Competition binding studies and protein modification suggest that C5, factor B, beta 1H, and properdin each bind to a distinct region on C3b.

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A novel transglutaminase-mediated post-translational modification of phospholipase A2 dramatically increases its catalytic activity.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(17)44886-1 ◽

1990 ◽

Vol 265 (28) ◽

pp. 17180-17188 ◽

Cited By ~ 4

Author(s):

E Cordella-Miele ◽

L Miele ◽

A B Mukherjee

Keyword(s):

Catalytic Activity ◽

Phospholipase A2 ◽

Post Translational Modification

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Electrochemical characterization of Cu(II) complexes of brain-related tau peptides

Canadian Journal of Chemistry ◽

10.1139/cjc-2020-0288 ◽

2021 ◽

Vol 99 (7) ◽

pp. 628-636

Author(s):

Camilla Golec ◽

Jose O. Esteves-Villanueva ◽

Sanela Martic

Keyword(s):

Metal Ions ◽

Tau Protein ◽

Metal Ion ◽

Differential Pulse ◽

Redox Couple ◽

Peptide Sequence ◽

Binding Studies ◽

Biologically Relevant ◽

Redox Active ◽

Competition Binding

Metal ion dyshomeostasis plays an important role in diseases, including neurodegeneration. Tau protein is a known neurodegeneration biomarker, but its interactions with biologically relevant metal ions, such as Cu(II), are not fully understood. Herein, the Cu(II) complexes of four tau R peptides, based on the tau repeat domains, R1, R2, R3, and R4, were characterized by electrochemical methods, including cyclic voltammetry, square-wave voltammetry, and differential pulse voltammetry in solution under aerobic conditions. The current and potential associated with Cu(II)/(I) redox couple was modulated as a function of R peptide sequence and concentration. All R peptides coordinated Cu(II) resulting in a dramatic decrease in the current associated with free Cu(II), and the appearance of a new redox couple due to metallo–peptide complex. The metallo–peptide complexes were characterized by the irreversible redox couple at more positive potentials and slower electron-transfer rates compared with the free Cu(II). The competition binding studies between R peptides with Cu(II) indicated that the strongest binding affinity was observed for the R3 peptide, which contained 2 His and 1 Cys residues. The formation of complexes was also evaluated as a function of peptide concentration and in the presence of competing Zn(II) ions. Data indicate that all metallo–peptides remain redox active pointing to the potential importance of the interactions between tau protein with metal ions in a biological setting.

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