Phytohormoneabscisicacid(ABA)wascriticalformanyplantgrowthanddevelopmentalprocessesincludingseedmaturation,germinationandresponsetoenvironmentalfactors.WiththepurposetodetectthepossibleABArelatedsignaltransductionpathways,wetriedtoisolateABA-regulatedgenesthroughcDNAmacroarraytechnologyusingABA-treatedriceseedlingasmaterials(undertreatmentfor2,4,8and12h).Of6144cDNAclonestested,37differentialclonesshowinginductionorsuppressionforatleastonetime,wereisolated.Ofthem30and7wereup-ordown-regulatedrespectively.Sequenceanalysesrevealedthattheputativeencodedproteinswereinvolvedindifferentpossibleprocesses,includingtranscription,metabolismandresistance,photosynthesis,signaltransduction,andseedmaturation.6cDNAcloneswerefoundtoencodeproteinswithunknownfunctions.RegulationbyABAof7selectedclonesrelatingtosignaltransductionormetabolismwasconfirmedbyreversetranscriptionPCR.Inaddition,somecloneswerefurthershowntoberegulatedbyotherplantgrowthregulatorsincludingauxinandbrassinosteroid,which,however,indicatedthecomplicatedinteractionsofplanthormones.PossiblesignaltransductionpathwaysinvolvedinABAwerediscussed.
