The programmed induction of meiotic DNA double-strand breaks (DSBs) by the evolutionarily conserved SPO-11 protein, which is structurally related to archaeal Topo VIA topoisomerases, triggers meiotic recombination. Identification of several meiosis-specific factors that are required for SPO-11-mediated DSB formation raises the question whether SPO-11 alone can cleave DNA. Here, we have developed procedures to express and purify C. elegans SPO-11 in a soluble, untagged, and monodispersed form. Our biochemical and biophysical analyses demonstrate that SPO-11 is monomeric and binds DNA, double-stranded DNA in particular. Importantly, SPO-11 does not exhibit DNA cleavage activity under a wide range of reaction conditions, suggesting that co-factors are needed for DSB induction activity. Our SPO-11 purification system and the findings reported herein should facilitate future mechanistic studies directed at delineating the mechanism of action of the SPO-11 ensemble in meiotic DSB formation.
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http://dx.doi.org/10.1038/s41598-017-02641-z | DOI Listing |
J Agric Food Chem
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Department of Food Science and Technology, School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, 2# Xuelin Road, Nanjing 210023, People's Republic of China.
Acrolein (ACR) present in vivo and in vitro can damage proteins and DNA, linking it to various chronic diseases. In this paper, ergothioneine (EGT), abundant in edible mushrooms, has been studied for its ability to trap ACR and its reaction pathway with ACR at high temperatures using ultraperformance liquid chromatography-mass spectrometry (UPLC-MS/MS). We synthesized the adducts (EGT-ACR-1 and EGT-ACR-2), elucidating their structure and reaction site through HRMS and nuclear magnetic resonance.
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January 2025
Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology (TUAT), 2-24-16 Naka-cho Koganei-shi, Tokyo 184-8588, Japan.
Nanopore sensing is widely used for single-molecule detection, originally applied to nucleic acids and now extended to protein sensing. Our study focuses on the complex conformational changes of peptides in nanopores, which may have implications for peptide fingerprinting and protein identification. Specifically, we investigated the interaction of a β-hairpin peptide (SV28) within an α-hemolysin (αHL) nanopore.
View Article and Find Full Text PDFSci Adv
January 2025
Université de Lorraine, INRAE, DynAMic, F-54000 Nancy, France.
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View Article and Find Full Text PDFPLoS One
January 2025
Department of Surgery, Asian Liver Center, Stanford University School of Medicine, Stanford, California, United States of America.
Patients with chronic hepatitis B infection (CHB) have an increased risk for death from liver cirrhosis and hepatocellular carcinoma (HCC). In the United States, only an estimated 37% of adults with chronic hepatitis B diagnosis without cirrhosis receive monitoring with at least an annual alanine transaminase (ALT) and hepatitis B deoxyribonucleic acid (DNA), and an estimated 59% receive antiviral treatment when they develop active hepatitis or cirrhosis. A Markov model was used to calculate the costs, health impact and cost-effectiveness of increased monitoring of adults with HBeAg negative inactive or HBeAg positive immune tolerant CHB who have no cirrhosis or significant fibrosis and are not recommended by the current American Association for the Study of Liver Diseases (AASLD) clinical practice guidelines to receive antiviral treatment, and to assess whether the addition of HCC surveillance would be cost-effective.
View Article and Find Full Text PDFNew Phytol
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Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, 9052, Belgium.
Precise gene-editing methods are valuable tools to enhance genetic traits. Gene editing is commonly achieved via stable integration of a gene-editing cassette in the plant's genome. However, this technique is unfavorable for field applications, especially in vegetatively propagated plants, such as many commercial tree species, where the gene-editing cassette cannot be segregated away without breaking the genetic constitution of the elite variety.
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