Endonuclease V (EndoV) initiates a major base-repair pathway for nitrosative deamination resulting from endogenous processes and increased by oxidative stress from mitochondrial dysfunction or inflammatory responses. We solved the crystal structures of Thermotoga maritima EndoV in complex with a hypoxanthine lesion substrate and with product DNA. The PYIP wedge motif acts as a minor groove-damage sensor for helical distortions and base mismatches and separates DNA strands at the lesion. EndoV incises DNA with an unusual offset nick 1 nucleotide 3' of the lesion, as the deaminated adenine is rotated approximately 90 degrees into a recognition pocket approximately 8 A from the catalytic site. Tight binding by the lesion-recognition pocket in addition to Mg(2+) and hydrogen-bonding interactions to the DNA ends stabilize the product complex, suggesting an orderly recruitment of downstream proteins in this base-repair pathway.
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http://dx.doi.org/10.1038/nsmb.1538 | DOI Listing |
bioRxiv
November 2024
Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), 97072 Würzburg, Germany.
Base editors create precise genomic edits by directing nucleobase deamination or removal without inducing double-stranded DNA breaks. However, a vast chemical space of other DNA modifications remains to be explored for genome editing. Here, we harness the bacterial anti-phage toxin DarT2 to append ADP-ribosyl moieties to DNA, unlocking distinct editing outcomes in bacteria versus eukaryotes.
View Article and Find Full Text PDFMetab Brain Dis
November 2024
Programa de Pós-Graduação em Bioquímica e Bioprospecção - Laboratório de Neuroquímica, Inflamação e Câncer, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Campus Universitário S/N, Capão do Leão, RS, Brazil.
Neuroinflammation is associated with many neurological disorders. Gallic acid (GA) has attracted significant attention due to its biological properties, such as neuroprotective, anti-inflammatory, and antioxidant effects. In this study, we evaluated the effects of GA in memory, TNF-α levels, oxidative stress, and activities of acetylcholinesterase (AChE), Na, K-ATPase and Ca-ATPase in the brain of mice exposed to lipopolysaccharide (LPS).
View Article and Find Full Text PDFNucleic Acids Res
December 2024
Department of Bioengineering, University of California Riverside, 900 University Avenue, 92512 Riverside, CA, USA.
CRISPR-based DNA adenine base editors (ABEs) hold remarkable promises to address human genetic diseases caused by point mutations. ABEs were developed by combining CRISPR-Cas9 with a transfer RNA (tRNA) adenosine deaminase enzyme and through directed evolution, conferring the ability to deaminate DNA. However, the molecular mechanisms driving the efficient DNA deamination in the evolved ABEs remain unresolved.
View Article and Find Full Text PDFCell
December 2024
Laboratory of Bacteriology, The Rockefeller University, New York, NY 10065, USA; Howard Hughes Medical Institute, The Rockefeller University, New York, NY 10065, USA. Electronic address:
Mutat Res Rev Mutat Res
December 2024
Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, China; Key Laboratory of Endocrine Glucose & Lipids Metabolism and Brain Aging, Ministry of Education, Shandong Provincial Hospital Affiliated to Shandong First Medical University, China; "Chuangxin China" Innovation Base of stem cell and Gene Therapy for endocrine Metabolic diseases, China; Shandong Engineering Research Center of Stem Cell and Gene Therapy for Endocrine and Metabolic Diseases, Jinan, Shandong 250021, China. Electronic address:
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