简介：Throughexploitingthehighhomologyofcerealcropgenes,membranouscDNAmicroarrayscontaining3311uniquericetranscripts(including1639cndosperm-derivedtranscriptsand1672maturestem-derivedtranscripts)wereusedformonitoringtheexpressionprofilesofl-leafstageseedlingsof4cerealcropspecies:rice,maize,sorghumandbarley.Afterhybridizingwith[P]labeledprobes,73.6%ofthearrayedgenesgeneratedreliablesignalsinallofthefourcerealcrops.Furtheranalysisrevealedthatamongthearrayedgenes,ahigherpercentageoftheendosperm-derivedtranscripts(86.6%)expressedthanthatofthematurestem-derivedgenes(60.9%),indicatingthatmostoftheendospermexpressedgenesfunctionedinyoungseedlingswhilcconsiderableamountofmaturestemtissueexpressedgenesdidnotexpress.Theseresultsalsoinferredthatsomegenesmightfunctiononlyatcertaindevelopmentalstages.Bycomparingtheobtainedprofdes,84geneswereidentifiedconstantlyexpressedinallthefourcerealcrops.Manyhousekeepinggenes,suchaspolyubiquitin,ubiquitinconjugatingenzymeandribosomalproteinswereincludedinthiscatalogue.Theexperimentalsoidentified14riceseedlingspecificallyexpressedgenes,including3bioticandabioticstressinducedgenesand1apoptosissuppressorencodinggeneBaxinhibitor-1.Thisinvestigationprovidedinvaluableinformationforcomparativegenomicsofgramineaemembers.

简介：Twostarch-branchingenzyme(SBE)inrice,isknowntobeakeyenzymeinamylopectinbiosynthesis.ThecDNAoftwoSBE(starch-branchingenzyme)genesSheIandShedencodingSBEⅠandSBEⅢ(twomajorisoformsinrice)wereclonedbyanimprovedRT-PCRtechnique,fromatemplatecDNAlibray,derivedfromthetotalmRNAsextractedfromtheimmatureseedsofajaponicariceWuyunjing7.DNAsequenceanalysisshowedthatthesizeoftheclonedSheIandShedcDNAswere2490and2481bplong,respectively,includingtheirentirecodingsequences.ComparisonanalysisindicatedthatthenucleotidesequenceofShe3wasthesameasthatofshed(GenbankAccessionNo.D16201)asreportedpreviously.Therewereonlyfourbase-pairsdifference,whichresultedinchangesoftwodeducedaminoacidsbetweentheclonedShe1cDNAandthereportedshe1(GenbankAccessionNo.D11082).TheclonedSheIandShedcDNAsmakeitpossibletoimprovericestarchqualitythroughgeneticengineering.