protein serine/threonine kinase activity histone H2AXS139 kinase activity https://github.com/geneontology/go-ontology/issues/25034 https://github.com/geneontology/go-ontology/issues/28520 https://github.com/geneontology/go-ontology/issues/30578 molecular_function 2011-08-22T01:13:34Z histone kinase activity (H2A.x-S139 specific) Note that the residue position corresponds to the canonical human H2AX histone (UniProtKB:P16104); this residue is conserved across all eukaryotes. 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. histone H2AS139 kinase activity histone kinase activity (H2A-S139 specific) bf GO:0035979 Catalysis of the reaction: histone H2AX-serine (position 139) + ATP = histone H2AX-phosphoserine (position 139) + ADP. This reaction is the addition of a phosphate group to the serine residue at position 139 of histone variant H2AX. histone H2AX kinase activity