Structure and Function of SNM1 Family Nucleases

Area of Science:

• Molecular Biology
• Genetics
• Biochemistry

Background:

• The SNM1 gene family comprises three human nucleases: SNM1A, SNM1B/Apollo, and SNM1C/Artemis.
• These nucleases play vital roles in DNA repair pathways such as homologous recombination and nonhomologous end-joining, alongside cell cycle regulation and telomere maintenance.

Approach:

• This review synthesizes recent research on the cellular and biochemical functions of SNM1 nucleases.
• It incorporates structural biology findings, including X-ray crystallography and cryo-electron microscopy (cryo-EM) data.
• Artificial intelligence (AI) tools like AlphaFold are utilized to predict protein structures and explore non-catalytic domain features.

Key Points:

• SNM1A, SNM1B/Apollo, and SNM1C/Artemis share a conserved catalytic domain (metallo-β-lactamase and CPSF-Artemis-SNM1-PSO2).
• SNM1A and SNM1B/Apollo function as exonucleases, while SNM1C/Artemis acts as an endonuclease.
• AI-driven structure predictions offer new insights into protein domains, complementing experimental structural data.

Conclusions:

• Understanding the SNM1 gene family is critical for comprehending DNA repair mechanisms.
• Integrating diverse structural and functional data, including AI predictions, enhances our mechanistic understanding of these nucleases.
• Further research combining structural biology and functional assays will elucidate the precise roles of SNM1 nucleases in cellular processes.