NUCLEASE

Nucleases are a type of hydrolytic enzymes that cleave the phosphodiester bonds between the sugars and the phosphate moieties of nucleic acids. The cleavage reactions may occur at the end or within the strand of DNA molecules, thus DNA nucleases are usually categorized as endonucleases and exonucleases. DNA nucleases catalyze the cleavage of phosphodiester bonds. These enzymes play a crucial role in various DNA repair processes, including DNA replication, base excision repair, nucleotide excision repair, mismatch repair, and double strand break repair. In recent years, new nucleases involved in various DNA repair processes have been reported, including Mus81: Mms4 (Eme1) complex and Artemis treated with V (D) J recombinant intermediate: DNA-PK complex. Defects in these nucleases can lead to genetic instability or severe immune deficiencies. Therefore, the structural biology of various nucleases is crucial for elucidating the molecular mechanisms of complex DNA repair mechanisms. The three-dimensional structural information of nucleases is rapidly accumulating, providing important insights into molecular structure and DNA recognition and cleavage mechanisms. This review focuses on the three-dimensional structure function relationship of nucleases, which are crucial for DNA repair processes.