Ribonucleotides in DNA

We report here the consequences of loss of Saccharomyces cerevisiae RNase H2 by comparing mRNA expression profiles in wild type yeast versus a strain lacking the RNH201 gene, encoding the catalytic subunit. Deleting RHN201 alters mRNA expression for hundreds of genes. Expression changes were based on seven biological replicates (3 from one batch and 4 from another batch) and are seen for many genes involved in stress responses and genome maintenance, consistent with a role of RNase H2 in removing ribonucleotides incorporated into DNA during replication. Differentially expressed genes include, those involved in ribosomal RNA processing and biogenesis and in tRNA modification, supports a role for RNase H2 in resolving R-loops formed during transcription of rRNA and tRNA. Other differentially expresses genes include putative or known helicases and nucleases maintenance of dsRNA viruses, which could be relevant to how mammalian RNase H2 dysfunction elicits an innate immune response leading to neurodegeneration. We examine the consequences of loss of Saccharomyces cerevisiae RNase H2 by comparing mRNA expression profiles in wild type yeast versus a strain lacking the RNH201 gene encoding the catalytic subunit. Expression changes were based on seven biological replicates (3 from one batch and 4 from another batch). For strain reference please see S.A. Nick McElhinny, et al, Genome instability due to ribonucleotide incorporation into DNA, Nat Chem Bio 6, 774-781 (2010).