histone arginine deiminase activity histone H2AR3 arginine deiminase activity https://github.com/geneontology/go-ontology/issues/23152 https://github.com/geneontology/go-ontology/issues/28520 https://github.com/geneontology/go-ontology/issues/30578 molecular_function histone-arginine deiminase activity (H2A-R3 specific) Catalysis of the reaction: H2O + histone 2A L-arginyl (position 3)= histone 2A L-citrullyl (position 3) + NH4+, resulting in histone H2A citrullination at position 3. histone H2A-R3 arginine deiminase activity Note that the residue position corresponds to the canonical human H2A2A histone (UniProtKB:Q6FI13); this residue seems to be only present in animals. Residue 1 is the first residue following removal of the initiating Methionine (Met). Note that each histone is encoded by multiple genes, and sequences may vary across different genes within an organism. The substrate for histone deiminase may be methyl-arginine, rather than arginine (see PMID:35197210 and PMID:16567635). GO:0140811 H2A-R3 citrullination 2022-05-11T10:07:04Z pg