3'-to-5'exoribonuclease that preferentially degrades DNA and RNA oligonucleotides composed of only two nucleotides . Binds and degrades longer oligonucleotides with a lower affinity . Plays dual roles in mitochondria, scavenging nanoRNAs (small RNA oligonucleotides of <5 nucleotides) that are produced by the degradosome and clearing short RNAs that are generated by RNA processing . Essential for correct initiation of mitochondrial transcription, degrading mitochondrial RNA dinucleotides to prevent RNA-primed transcription at non-canonical sites in the mitochondrial genome . Essential for embryonic development (By similarity). ; [Isoform 3]: 3'-to-5'exoribonuclease that preferentially degrades DNA and RNA oligonucleotides composed of only two nucleotides.
Mitochondrion intermembrane space . Mitochondrion matrix . Mitochondrion . Cytoplasm . Nucleus .; [Isoform 3]: Cytoplasm . Nucleus .
Highly expressed in the heart and at lower levels in the lymph nodes, brain, lung, liver, spleen and thymus.