The primary function of endoV differs significantly in prokaryotes and eukaryotes, as suggested by studies on the E. coli and human orthologs.

In prokaryotes endoV is primarily a deoxyribonuclease involved in DNA repair of deoxyinosine introduced into the genome by deamidation of adenine bases (EC 3.1.21.7).

[2] However, it has broad substrate specificity and can also act on other types of DNA lesions[2] as well as on inosine-containing RNA.

[3] In eukaryotes endoV is primarily a ribonuclease and cleaves single-stranded RNA at the 3' position relative to an inosine base, which may be present due to RNA editing by deaminase enzymes (EC 3.1.26.-).

[4] The human endoV localizes to the cytoplasm and nucleoli, suggesting a possible role in processes involving ribosomal RNA.