Generation of ribonuclease H2 A subunit (RH2A)-knockout HEK293 cells and analysis of the ribonucleotide content of their genomic DNA

Mammalian ribonuclease (RNase) H2 is a trimeric protein consisting of three subunits (catalytic A and accessory B and C).RNase H2 is involved in the removal of misincorporated ribonucleotides from genomic DNA and RNA strands from RNA/DNA hybrids.In humans, mutations in RNase H2 gene have been linked to a severe neuroinflammatory disorder, Aicardi-Goutières syndrome (AGS).Here, we constructed RNase H2 A subunit (RH2A) knockout human embryonic kidney 293 (HEK293) cells.Knockout cells lacked the RNase H2 activity.However, unlike our previous results with mouse fibroblast NIH3T3 cells, the knockout HEK293 cells did not exhibit an accumulation of ribonucleotides in genomic DNA.These results suggest that the effects of knockout of RNase H2 on accumulation of ribonucleotides differ depending on cell species.