Ribonuclease P (, "RNase P") is a type of ribonuclease which cleaves RNA. Ribonuclease cleaves phosphodiester bonds between RNA nucleotides. Pol gene products include enzymes reverse transcriptase, integrase and ribonuclease H domains. RNA-dependent DNA polymerase activity, ribonuclease H (RNAse H), and DNA-dependent DNA polymerase activity. The p66 subunit has two domains, a polymerase and ribonuclease H. One such enzyme is Ribonuclease A (RNase A), a protein enzyme. After the RISC localizes to the target mRNA, the RNA is cleaved by a ribonuclease. In eukaryotes, ribonuclease H1 is involved in DNA replication of the mitochondrial genome. This is cleaved by RNase III, an RNA-specific ribonuclease, to form a crRNA/tracrRNA hybrid. Mammalian RIs are unable to bind certain pancreatic ribonuclease family members from other species. Weiss has considered the mechanisms by which the phosphodiesterase antagonises Ribonuclease L. S-tag is the name of an oligopeptide derived from pancreatic ribonuclease A (RNase A). Common examples include the ferredoxin fold, ribonuclease A, and the SH2 domain. The ribonuclease activity of ECP is not essential for cytotoxicity. Bovine pancreatic ribonuclease is one of the classic model systems of protein science.