RNA endonuclease activity producing 5'-phosphomonoesters, hydrolytic mechanism ribonuclease IV activity https://github.com/geneontology/go-ontology/issues/30193 GO:0033893 molecular_function endoribonuclease IV activity Catalysis of the endonucleolytic cleavage of poly(A) to fragments terminated by 3'-hydroxy and 5'-phosphate groups. MetaCyc:3.1.26.6-RXN EC:3.1.26.6