Complex Roles of NEIL1 and OGG1: Insights Gained from Murine Knockouts and Human Polymorphic Variants

Area of Science:

• Genetics and Molecular Biology
• Genomic Stability
• DNA Repair Mechanisms

Background:

• DNA glycosylases initiate base excision repair (BER) for genomic integrity in nuclear and mitochondrial DNA.
• OGG1 and NEIL1 exhibit overlapping substrate recognition, such as for FapyGua, but possess distinct substrate specificities and repair chemistries.
• Studies in knockout murine models reveal complex in vivo roles for NEIL1 and OGG1, with diverse phenotypic manifestations.

Purpose of the Study:

• To compare the roles of NEIL1 and OGG1 in maintaining genomic integrity.
• To analyze insights gained from knockout/transgenic mouse models and human disease susceptibility.
• To elucidate the differential impacts of NEIL1 and OGG1 deficiencies on cancer and metabolic health.

Main Methods:

• Comparative analysis of NEIL1 and OGG1 functions in DNA repair.
• Phenotypic characterization of murine models deficient in Neil1 or Ogg1.
• Investigation of human disease susceptibility linked to polymorphic variants of these genes.

Main Results:

• OGG1 deficiency confers resistance to carcinogenesis, while NEIL1 deficiency increases cancer susceptibility.
• Both OGG1 and NEIL1 deficiencies lead to age- and diet-induced metabolic syndrome.
• Mitochondrial expression of OGG1 can ameliorate metabolic syndrome phenotypes.
• OGG1 also functions as a transcription factor regulating inflammation.

Conclusions:

• NEIL1 and OGG1 play critical, yet distinct, roles in maintaining genomic stability and overall health.
• Differences in their nuclear and mitochondrial functions contribute to varied disease susceptibilities.
• Understanding these glycosylases is crucial for addressing cancer and metabolic disorders.