24CA

Crystal structure of nuclease MYG1(D93A) bound to Mn2+ and AMP

24CA の概要

• エントリーDOI: 10.2210/pdb24ca/pdb
• 分子名称: MYG1 exonuclease, ADENOSINE MONOPHOSPHATE, MANGANESE (II) ION, ... (4 entities in total)
• 機能のキーワード: myg1, nuclease, mn2+, dhh family, hydrolase
• 由来する生物種: Homo sapiens (human)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 37636.90

構造登録者

Ding, J.,Lan, C.,Chen, Z. (登録日: 2026-02-27, 公開日: 2026-04-22)

主引用文献

Lan, C.,Chen, Z.,Wang, G.,Ding, J.
Biochemical and structural studies reveal the substrate specificity and catalytic mechanism of MYG1 as a two-metal ion-dependent 3'→5' exonuclease.
Acta Biochim.Biophys.Sin., 2026

PubMed Abstract: Nucleases are a class of enzymes that specifically cleave nucleic acids in all living organisms. They play crucial roles in essential biological processes, including the regulation of gene expression, DNA damage repair, and RNA processing and degradation. MYG1 (melanocyte proliferating gene 1) is a highly conserved eukaryotic protein that exhibits 3'→5' exonuclease activity. This study systematically characterizes the enzymatic properties of MYG1 and determines its structures in complexes with metal ions and various mono- and poly-(deoxy)nucleotides. The functional roles of key residues involved in metal ion binding and substrate binding in the catalytic reaction are examined through site-directed mutagenesis, enzymatic activity assay, and structure determination. Our biochemical and structural data together demonstrate that MYG1 is a Mn - or Mg -dependent 3'→5' exonuclease capable of cleaving a variety of nucleic acids with different structures. It exhibits the highest activity for single-stranded RNA and a nucleotide preference for U in single-stranded RNA and dT in single-stranded DNA. Mechanistically, MYG1 functions as a dimer, with the active site formed by the catalytic domain of monomer 1 and the substrate-binding domain of monomer 2, and cleaves nucleic acids through a two-metal ion-mediated catalytic mechanism. These findings establish a molecular basis for further investigations into the biological functions and molecular mechanisms of MYG1 within cells and its potential roles in human diseases.

PubMed: 41964352
DOI: 10.3724/abbs.2026058

実験手法

X-RAY DIFFRACTION (1.93 Å)