G:U mismatches resulting from deamination of cytosine are the most common promutagenic lesions occurring in DNA. Uracil is removed in a base-excision repair pathway by uracil DNA-glycosylase (UDG), which excises uracil from both single- and double-stranded DNA. Recently, a biochemically distinct family of DNA repair enzymes has been identified, which excises both uracil and thymine, but only from mispairs with guanine. Crystal structures of the mismatch-specific uracil DNA-glycosylase (MUG) from E. coli, and of a DNA complex, reveal a remarkable structural and functional homology to UDGs despite low sequence identity. Details of the MUG structure explain its thymine DNA-glycosylase activity and the specificity for G:U/T mispairs, which derives from direct recognition of guanine on the complementary strand.

Download full-text PDF

Source
http://dx.doi.org/10.1016/s0092-8674(00)80904-6DOI Listing

Publication Analysis

Top Keywords

uracil dna-glycosylase
8
excises uracil
8
dna
5
uracil
5
crystal structure
4
structure gt/u
4
gt/u mismatch-specific
4
mismatch-specific dna
4
dna glycosylase
4
glycosylase mismatch
4

Similar Publications

Targeted deaminase-free T-to-G and C-to-K base editing in rice by fused human uracil DNA glycosylase variants.

Plant Biotechnol J

January 2025

Institute of Crop Sciences/National Nanfan Research Institute, Chinese Academy of Agricultural Sciences (CAAS), and Key Laboratory of Gene Editing Technologies (Hainan), Ministry of Agriculture and Rural Affairs, Sanya, China.

View Article and Find Full Text PDF

The cytotoxic mechanisms of thymidylate synthase inhibitors, such as the multitarget antifolate pemetrexed, are not yet fully understood. Emerging evidence indicates that combining pemetrexed with histone deacetylase inhibitors (HDACi) may enhance therapeutic efficacy in non-small cell lung cancer (NSCLC). To explore this further, A549 NSCLC cells were treated with various combinations of pemetrexed and the HDACi MS275 (Entinostat), and subsequently assessed for cell viability, cell cycle changes, and genotoxic markers.

View Article and Find Full Text PDF

Genome-Wide A → G and C → T Mutations Induced by Functional TadA Variants in .

ACS Synth Biol

January 2025

Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin 300072, P. R. China.

The fusion expression of deoxyribonucleic acid (DNA) replication-related proteins with nucleotide deaminase enzymes promotes random mutations in bacterial genomes, thereby increasing genetic diversity among the population. Most previous studies have focused on cytosine deaminase, which produces only C → T mutations, significantly limiting the variety of mutation types. In this study, we developed a fusion expression system by combining DnaG (RNA primase) with adenine deaminase TadA-8e (DnaG-TadA) in , which is capable of rapidly introducing A → G mutations into the genome, resulting in a 664-fold increase in terms of mutation rate.

View Article and Find Full Text PDF

Continuous Evolution of Protein through T7 RNA Polymerase-Guided Base Editing in .

ACS Synth Biol

January 2025

The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China.

targeted mutagenesis technologies are the basis for the continuous directed evolution of specific proteins. Here, an efficient mutagenesis system (CgMutaT7) for continuous evolution of the targeted gene in was developed. First, cytosine deaminase and uracil-DNA glycosylase inhibitor were sequentially fused to T7 RNA polymerase using flexible linkers to build the CgMutaT7 system, which introduces mutations in targeted regions controlled by the T7 promoter.

View Article and Find Full Text PDF

Straightforward genotyping can provide timely diagnostic information for diseases prevention and treatment. Taking advantages of speediness and convenience, although numerous genotyping strategies combined loop-mediated isothermal amplification (LAMP) and lateral flow have been reported to satisfy the demand of point-of-care test, the false positive result caused by aerosol and primer dimer as an innate conflict seriously limits their practical application. In this study, both aerosol and primer dimer as extrinsic and intrinsic inducements respectively are first broken through at one stroke based on an integrated immunochromatographic biosensor.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!