The RNase PH-like exosome proteins, PNPase and RNase PH all belong to the RNase PH family of RNases and are phosphorolytic exoribonucleases, meaning that they use inorganic phosphate to remove nucleotides from the 3' end of RNA molecules.
RNase PH-like enzymes, PNPase and RNase PH, are part of the RNase PH family that degrades RNA molecules using inorganic phosphate to remove nucleotides from their 3' ends, a process also employed by other phosphorolytic exoribonucleases.