Traditional methods to assay enzymatic cleavage of DNA are discontinuous and time consuming. In contrast, recently developed fluorescence methods are continuous and convenient. However, no fluorescence method has been developed for single-stranded DNA digestion. Here we introduce a novel method, based on molecular beacons, to assay single-stranded DNA cleavage by single strand-specific nucleases. A molecular beacon, a hairpin-shaped DNA probe labeled with a fluorophore and a quencher, is used as the substrate and enzymatic cleavage leads to fluorescence enhancement in the molecular beacon. This method permits real time detection of DNA cleavage and makes it easy to characterize the activity of DNA nucleases and to study the steady-state cleavage reaction kinetics. The excellent sensitivity, reproducibility and convenience will enable molecular beacons to be widely useful for the study of single-stranded DNA cleaving reactions.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC102637 | PMC |
http://dx.doi.org/10.1093/nar/28.11.e52 | DOI Listing |
Heliyon
January 2025
Department of Otorhinolaryngology Head and Neck Surgery, Children's Hospital Capital Institute of Pediatrics, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
(, Hi) is an opportunistic bacterium that colonizes the upper respiratory tract of humans and frequently causes meningitis, pneumonia, sepsis, and other severe infections in children. Early and accurate detection of is essential for effective diagnosis and treatment. In this study, we established a novel diagnostic method by integrating the CRISPR-Cas12a detection platform with multiple cross-displacement amplification (MCDA), termed the Hi-MCDA-CRISPR assay.
View Article and Find Full Text PDFMol Med
January 2025
Research Institute, National Cancer Center, Goyang-Si, Gyeonggi-Do, 10408, Republic of Korea.
Background: Double-strand breaks (DSBs) are primarily repaired through non-homologous end joining (NHEJ) and homologous recombination (HR). Given that DSBs are highly cytotoxic, PARP inhibitors (PARPi), a prominent class of anticancer drugs, are designed to target tumors with HR deficiency (HRD), such as those harboring BRCA mutations. However, many tumor cells acquire resistance to PARPi, often by restoring HR in HRD cells through the inactivation of NHEJ.
View Article and Find Full Text PDFBiochem J
January 2025
School of Science, University of Waikato, Hamilton, Waikato, 3216, New Zealand.
DNA-joining by ligase and polymerase enzymes has provided the foundational tools for generating recombinant DNA and enabled the assembly of gene and genome-sized synthetic products. Xenobiotic nucleic acid (XNA) analogues of DNA and RNA with alternatives to the canonical bases, so-called 'unnatural' nucleobase pairs (UBP-XNAs), represent the next frontier of nucleic acid technologies, with applications as novel therapeutics and in engineering semi-synthetic biological organisms. To realise the full potential of UBP-XNAs, researchers require a suite of compatible enzymes for processing nucleic acids on a par with those already available for manipulating canonical DNA.
View Article and Find Full Text PDFVirus Evol
January 2025
MRC-University of Glasgow Centre for Virus Research, The University of Glasgow, Glasgow G61 1QH, United Kingdom.
Anelloviruses are a group of small, circular, single-stranded DNA viruses that are found ubiquitously across mammalian hosts. Here, we explored a large number of publicly available human microbiome datasets and retrieved a total of 829 anellovirus genomes, substantially expanding the known diversity of these viruses. The majority of new genomes fall within the three major human anellovirus genera: , and , while we also present new genomes of the under-sampled , and genera.
View Article and Find Full Text PDFSmall Methods
January 2025
Hangzhou Institute of Medicine, Chinese Academy of Sciences, Hangzhou, Zhejiang, 310018, China.
Colorectal cancer (CRC) remains a significant global health challenge, underscoring the need for innovative therapeutic strategies. Oncogenic miRNAs (oncomiRs) play a significant biological role in the initiation and progression of colorectal cancer. Inspired by the cooperative mechanisms of plant nanovirus, which employ multiple circular single-stranded DNA (CssDNA) genomes, it is hypothesized that the development and delivery of CssDNA to target oncomiRs would achieve therapeutic benefits in CRC.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!