简介：SulfatecanbeactivatedbyATPsulfurylaseandadenosine5’-phosphosulfatekinase(APSK)invivo.RecentstudiessuggestedthatAPSKinArabidopsisthalianaregulatedthepartitionbetweenAPSreductionandphosphorylationanditsactivitycanbemodulatedbycellularredoxstatus.InordertostudyregulationofAPSKinrice(OsAPSK),OsAPSK1genewasclonedanditsactivitywasanalyzed.OsAPSK1C36andC69werefoundtobetheconservedcounterpartsofC86andC119,whichinvolvedindisulfideformationinAtAPSK.C36A/C69AOsAPSK1doublemutationwasmadebysitedirectedmutagenesis.OsAPSK1anditsmutantwereprokaryoticallyover-expressedandpurified,andthenassayedforAPSphosphorylationactivity.OsAPSK1activitywasdepressedbyoxidizedglutathione,whiletheactivityofitsmutantwasnot.Furtherstudiesinthecasethatoxidativestresswillfluctuateinvivo3’-phosphoadenosine-5’-phosphosulfatecontent,andallAPSKisoenzymeshavesimilarregulationpatternsarenecessarytobeperformed.