NEIL1 mRNA splicing variants are expressed in normal mouse organs

Area of Science:

• Molecular Biology
• DNA Repair Mechanisms

Background:

• Oxidized pyrimidines are repaired by base excision repair, initiated by DNA glycosylases.
• NEIL1 is a key mammalian DNA glycosylase for repairing oxidized pyrimidines.

Purpose of the Study:

• Investigate the expression of two putative variant mouse NEIL1 (mNEIL1) mRNAs in normal mouse organs.
• Determine the enzymatic activity and regulatory potential of mNEIL1 variant proteins.

Main Methods:

• Reverse transcription-PCR (RT-PCR) to detect mRNA expression in 9 mouse organs.
• Immunoblot analysis of nuclear extracts to identify protein variants.
• Recombinant protein expression and in vitro enzymatic activity assays.

Main Results:

• Both mNEIL1 variant mRNAs were expressed in all 9 normal mouse organs examined.
• Immunoblotting detected full-length mNEIL1 and two variant proteins in mouse liver nuclear extracts.
• Recombinant variant proteins lacked enzymatic activity, but variant 1 modulated full-length mNEIL1 activity.

Conclusions:

• mNEIL1 mRNA variants are widely expressed in normal mouse tissues.
• Variant 1 protein may play a regulatory role in NEIL1-mediated DNA repair, despite lacking intrinsic enzymatic activity.