calcium ion binding. similar to hypothetical protein OsJ_014860 [Oryza sativa (japonica cultivar-group)] (GB:EAZ31377.1); similar to OSJNBb0065J09.4 [Oryza sativa (japonica cultivar-group)] (GB:CAE05708.1); contains InterPro domain Photosystem II oxygen evolving complex protein PsbQ; (InterPro:IPR008797)