21Sugarcane:AMajorSourceofSweetness,Alcohol,andBio-energy503
incomesandadecreaseintheuseofpesticides(http://www.isaaa.org)overthelast10years.Besidesdeliveringsuchsuccessfulagriculturalproducts,thistechnologyalsooffersthepossibilityofstudyingthethousandsofplantgenes(withknownandunknownfunctions)thathavebeenproducedbynumerousgenomeprogramscon-ductedthroughouttheworld(Dongetal.2005).Asageneralrulethesenewgenesaresilencedorover-expressed,creatingopportunitiestostudytheirfunctionintheplantandtoproducenewphenotypesnotpossiblethroughconventionalbreeding(Galun2005;Mullerr2006).
The?rstexamplesoftheexpressionofexoticgenesinsugarcaneplantswereobtainedbytheinsertionofgenesconferringantibioticandherbicideresistance(BowerandBirch1992;Gallo-MeagherandIrvine1996).Formanyyearsnow,thegenetictransformationofsugarcanehasbeenarealityindifferentlabora-toriesaroundtheworld.Theproductionofherbicide-resistantplantsisnowacommonpractice(Falcoetal.2000;Manickavasagametal.2004)andagronom-icalperformanceandinheritancestudiesofplantscontainingthistraithavebeenperformedinthe?eld(LeibbrandtandSnyman2003;Butter?eldetal.2002).Insect-resistantsugarcaneplantswere?rstproducedbytransformationwithatrun-catedversionoftheBacillusthuringiensiscryIAbgeneandtheplantsproducedverylowamountsoftheprotein,presentingsomelarvicidalactivity(Arencibiaetal.1997).Bragaetal.(2001,2003)reportedtheproductionofanumberoftransgeniceventsresistanttosugarcaneborerintwocommercialsugarcaneculti-vars.ThegeneusedwasareconstructedversionofcryIAbandtheplantsshowedhighresistanceundergreenhouseand?eldconditions.Recently,atruncatedver-sionoftheB.thuringiensiscryIAcgenewasexpressedinsugarcaneplantsbyWengetal.(2006),andsigni?cantproteinlevelsandinsectresistancewereob-tainedfromatleasttwosugarcaneclones.Otherstrategieshavebeenusedtoobtaininsect-resistantsugarcaneplantsusinggenesfromvarioussources.Nuttetal.(1999)andNutt(2005)obtainedtransgenicsugarcaneplantsexpressingei-therthepotatoproteinaseinhibitorIIorthesnowdroplectingene,whichwereabletoreducetheweightofthecanegrublarvaefeedingonthem.TransgenicplantscontainingthesnowdroplectingenewerealsoreportedbyChenetal.(2004)withnoinformationoninsectresistancestudies.FalcoandSilva-Filho(2003)ex-pressedthesoybeanKunitzandBowman-Birktrypsininhibitorsinsugarcane,ob-tainingareductioningrowthofthesugarcaneborerlarvaefeedingontransgenicplants,withnomortality.Differentgroupshavereportedonresistancetoviraldiseasesinsugarcane:forsugarcanemosaicvirus(SCMV)(Joyceetal.1998;Ingelbrechtetal.1999);forFijidiseasevirus(FDV)(McQualteretal.2001);andforsugarcaneyellowleafvirus(SCYLV)(Rangeletal.2003).Eventhoughsugarcanegeneticengineeringhasdemonstratedhighpotential,therehasbeennocommercialreleaseoftransgenicsugarcaneeitherduetointellectualprop-ertyconsiderationsormoreprobablytoindustrialconcernsoverpublicpercep-tion.Theseconstraintsoncommercialreleasearelikelytocontinueinthenearfuture.Theeasewithwhichmanysugarcanegenotypescannowbetransformed,togetherwiththeidenti?cationofthesequencesofthousandsofgenesthatthis
504A.D’Hontetal.
plantexpresses,raisethepossibilityofalteringtheexpressionofspeci?cgenesintheplantandidentifyingtheeffectsthismodi?cationhasontheplant’sphe-notype.ThedevelopmentofRNAiandanti-sensetechnologyallowsforgenedown-regulationeveninahighpolyploidsituation.Non-?oweringplantsofaheavily?oweringsugarcanevarietywereproducedthroughtheanti-senseexpres-sionofasinglecandidate?owerdevelopmentgenefoundintheSucestdatabase(Figueiredo2003).Floweringisundesirableinsugarcanecommercial?elds.WuandBirch(2007)showedthattheexpressionofaheterologoussucroseisomerasegenedirectedtowardsthevacuoleoftransgenicsugarcaneplantsresultedinplantscapableofdoublingthetotalsugarsstoredinmatureculms.Intheseplants,theamountofstoredsucrosewasthesameasincontrolnon-transgenicplantsandtheincreaseintotalsugarwasduetotheaccumulationofisomaltulose,asucroseisomer.Thetransgenicplantswithenhancedsugaraccumulationalsoshowedin-creasedphotosynthesis,sucrosetransportandsinkstrength.Down-regulationandover-expressionofthegenesinvolvedincarbohydratemetabolismisthetopicofmanystudies,withtheaimofincreasingthecontentofsucroseandothermetabolites.
Inthelastfewyears,sugarcanehasalsoturnedintoatargetfortheproductionofnovelproductssuchasbiopolymers(McQualteretal.2005)andasaproducerofpharmaceuticalproteinswithdifferentproperties(Wangetal.2005).Theplantiswell-suitedtotheseapproachesduetosomeofitscharacteristicssuchasvegetativepropagation,theabsenceof?oweringinmostcommercialcultivars,theproductionofalargebiomass,thelargeamountofcarbonpartitionedintosucrose(upto42%ofthestalkdryweight),andamobilepoolofhexosesugarsthroughoutmostofitslife.TheproductionofbiopolymerswasobtainedbyMcQualteretal.(2005)insug-arcaneplants,accumulatingupto7.3%and1.5%dryweightofp-hydroxybenzoicacidinleafandstemtissue,respectively.Thisproductwasquantitativelyconvertedtoglucoseconjugatesbyendogenousuridinediphosphate-glucosyltransferasesandpresumablystoredinthevacuole.InitialstepstoproducepharmaceuticalproteinsweretakenwhenWangetal.(2005)successfullyproducedthehumangranulocytemacrophagecolony-stimulatingfactor(GM-CSF)insugarcane.Unfortunately,inthe?eld,theplantswereabletoaccumulateonly0.02%ofthetotalsolubleproteinasGM-CSF.
Inmonocots,themostfrequentlyusedpromotersarethemaizeubiquitinUbi-1andthericeactinact1.Eventhoughtheymaintainarelativelyconstantexpres-sionpattern,theyshowdistinctexpressionpatternsindifferentspecies,celltypes,andcultivationconditions(Neuteboometal.2002).Theidenti?cationofsugar-canetissue-speci?cpromotersisanimportantstepthatwillallowcontrolledgeneexpressionsothatnovelproductscanbeaccumulatedinthedesiredpartoftheplant,suchasintheleavesorstemparenchymacells.Afewpromotersfromsug-arcanegeneshavebeentestedinthepast,withlimitedsuccess(Birchetal.1995;Weietal.1999,2003;vanderMerweetal.2003).Again,thelargenumberofsugarcanegenesavailable,coupledwithstudiestounderstandwhenandwheretheyareexpressed,becomeimportanttoolstoidentifyregulatorysequencesthatcanbeusedtodrivespeci?cgenes.
21Sugarcane:aMajorSourceofSweetness,Alcohol,andBio-energy505
21.7Perspectives
SugarcaneMendeliangeneticshasliterallystartedwiththeadventofmolecularinves-tigationtechniques.The?rstmonofactorialsegregationsandthe?rstgeneticlinkagewereobervedlessthantwentyyearsago(Glaszmannetal.1989).Manyevolution-aryquestionshavebeenaddressed,con?rminghypothesesorconcludingearlierde-batesandoccasionallythrowingnewlightandimprovingoverallunderstanding.Thegenomehasbecomelessmysterious,althoughitscomplexityhasbeencon?rmedformanyaspects.Shortcutshavebeenidenti?edthankstosyntenywithothergrasses,andtheavailabilityofthesorghumsequencewillshortlyinitiateanewroundofprogress.TheremarkableeffortmadewithsugarcaneESTsisyieldingawealthycatalogofgenes,whosedocumentationstartstoopennewperspectivesforbreed-ingbetter-adaptedsugarcane.Theworldwiderealizationofthecentralimportanceofbio-energywillundoubtedlyfosterattentiononsugarcanephysiologyandgenetics.
References
AbeH,Yamaguchi-ShinozakiK,UraoT,IwasakiT,HosokawaD,etal.(1997)RoleofArabidopsisMYCandMYBhomologsindrought-andabscisicacid-regulatedgeneexpression.PlantCell9:1859–1868
AitkenKS,JacksonPA,McIntyreCL(2005)AcombinationofAFLPandSSRmarkersprovidesextensivemapcoverageandidenticationofhomo(eo)logouslinkagegroupsinasugarcanecultivar.TheorApplGenet110:789–801
AlixK,BaurensFC,PauletF,GlaszmannJC,D’HontA(1998)IsolationandcharacterizationofasatelliteDNAfamilyintheSaccharumcomplex.Genome41:854–864
AlixK,PauletF,GlaszmannJC,D’HontA(1999)Inter-Alulikespecies-speci?csequencesintheSaccharumcomplex.TheorApplGenet6:962–968
Al-JanabiSM,HoneycuttRJ,McClellandM,SobralBWS(1993)AgeneticlinkagemapofSac-charumspontaneumL.‘SES208’.Genetics134:1249–1260
Al-JanabiSM,HoneycuttRJ,SobralBW(1994)ChromosomeassortmentinSaccharum.TheorApplGenet89:959–963
AraújoPG,RossiM,JesusEM,Saccaro-JuniorNL,KajiharaD,etal.(2005)Transcriptionallyactivetransposableelementsinrecenthybridsugarcane.PlantJ44(5):707–17
ArceneauxG(1967)Cultivatedsugarcanesoftheworldandtheirbotanicalderivation.ProcIntSocSugarCaneTechnol12:844–854
ArencibiaA,VazquezRI,PrietoD,etal.(1997)Transgenicsugarcaneplantsresistanttostemborerattack.MolBreeding3(4):247–255
ArrudaP(2001)Sugarcanetranscriptome.Alandmarkinplantgenomicsinthetropics.GeneticsMolBiol24:1–296
AsnaghiC,PauletF,KayeC,GrivetL,DeuM,etal.(2000)ApplicationofsyntenyacrossPoaceaetodeterminethemaplocationofasugarcanerustresistancegene.TheorApplGenet101:962–969
AsnaghiC,RoquesD,RuffelS,KayeC,HoarauJ-Y,etal.(2004)Targetedmappingofasugarcanerustresistancegene(Bru1)usingbulkedsegregantanalysisandAFLPmarkers.TheorApplGenet108:759–764
BesseP,McIntyreCL,BerdingN(1997)CharacterisationofErianthussect.RipidiumandSaccha-rumgermplasm(Andropogoneae–Saccharinae)usingRFLPmarkers.Euphytica93:283–292BirchRG,BowerR,ElliotA,PotierB,FranksT,etal.(1995)Expressionofforeigngenesinsugarcane.ProcIntlSocSugarCaneTechnol22:368–373
506A.D’Hontetal.
BoddeyRM,UrquiagaS,AlvesBJR,ReisV(2003)Endophyticnitrogen?xationinsugarcane:presentknowledgeandfutureapplications.PlantandSoil252:139–149
BoivinK,DeuM,RamiJF,TroucheG,HamonP(1999)TowardsasaturatedsorghummapusingRFLPandAFLPmarkers.TheorApplGenet98:320–328
BowerNI,CasuRE,MacleanDJ,ReverterA,ChapmanSC,etal.(2005)Transcriptionalresponseofsugarcanerootstomethyljasmonate.PlantSci168:761–772
BowerR,BirchRG(1992)Transgenicsugarcaneplantsviamicroprojectilebombardment.PlantJ2(3):409–416
BowersJE,AbbeyC,AndersonS,ChangC,DrayeX,etal.(2003)Ahigh-densitygeneticrecom-binationmapofsequence-taggedsitesforsorghum,asaframeworkforcomparativestructuralandevolutionarygenomicsoftropicalgrainsandgrasses.Genetics165(1):367–86
BowyerJR,LeegoodRC(1997)Photosynthesis.In:DayPM,HarboneJB(eds)Plantbiochemistry.AcademicPress,SanDiego,pp49–110
BragaDPV,ArrigoniEDBBurnquistWL,Silva-FilhoMC,UlianEC(2001)AnewapproachforcontrolofDiatraeasaccharalis(Lepidoptera:Crambidae)throughtheexpressionofaninsecti-cidalCryIa(b)proteinintransgenicsugarcane.ProcIntSocSugarCaneTechnol24(2):331–336BragaDPV,ArrigoniEDB,Silva-FilhoMC,UlianEC(2003)ExpressionoftheCry1Abproteiningeneticallymodi?edsugarcaneforthecontrolofDiatraeasaccharalis(Lepidoptera:Cram-bidae).JNewSeeds5:209–222
BrandesEW(1956)Origin,dispersalanduseinbreedingoftheMelanesiangardensugarcanesandtheirderivatives,Saccharumof?cinarumL.ProcIntSocSugarCaneTechnol9:709–750BremerG(1961)Problemsinbreedingandcytologyofsugarcane.Euphytica10:59–78
BrownNJ,ParsleyK,HibberdJM(2005)ThefutureofC4research-maize,FlaveriaorCleome?TrendsPlantSci10:215–221
BundockP,HooykaasP(2005)AnArabidopsishAT-liketransposaseisessentialforplantdevel-opment.Nature436:282–284
BurnquistWL,SorrellsME,TanksleyS(1992)CharacterizationofgeneticvariabilityinSaccha-rumgermplasmbymeansofrestrictionfragmentlengthpolymorphism(RFLP)analysis.ProcIntSocSugarCaneTechnol21:355–365
Butter?eldMK,D’HontA,BerdingN(2001)Thesugarcanegenome:asynthesisofcurrentunder-standing,andlessonsforbreedingandbiotechnology.ProcSocAfrSugarcaneTechnolAssn75:1–5
Butter?eldMK,IrvineJE,GarzaMV,MirkovE(2002)Inheritanceandsegregationofvirusandherbicideresistancetransgenesinsugarcane.TheorApplGenet104(5):797–803
CaiQ,AitkenKS,PiperidisG,JacksonPA,McIntyreCL(2005)ApreliminaryassessmentofthegeneticrelationshipbetweenErianthusrockiiandthe“SaccharumComplex”usingmicrosatel-liteandAFLPmarkers.PlantSci169:976–984
CalsaJrT,FigueiraA(2007)Serialanalysisofgeneexpressioninsugarcane(Saccharumspp.)leavesrevealedalternativeC4metabolismandputativeantisensetranscripts.PlantMolBiol63,745–62
CarsonDL,BothaFC(2000)Preliminaryanalysisofexpressedsequencetagsforsugarcane.CropSci40:1769–1779
CarsonDL,BothaFC(2002)Genesexpressedinsugarcanematuringinternodaltissue.PlantCellRep20:1075–1081
CasacubertaJM,SantiagoN(2003)PlantLTR-retrotransposonsandMITEs:controloftransposi-tionandimpactontheevolutionofplantgenesandgenomes.Gene5:311:1–11
CasuR,DimmockC,ThomasM,BowerN,KnightD,etal.(2001)Geneticandexpressionpro?l-inginsugarcane.ProcIntSocSugarCaneTechnol24:542–546
CasuRE,GrofCP,RaeAL,McIntyreCL,DimmockCM,etal.(2003)Identi?cationofanovelsugartransporterhomologuestronglyexpressedinmaturingstemvasculartissuesofsugarcanebyexpressedsequencetagandmicroarrayanalysis.PlantMolBiol52:371–86
CasuRE,DimmockCM,ChapmanSC,GrofCP,McIntyreCL,etal.(2004)Identi?cationofdifferentiallyexpressedtranscriptsfrommaturingstemofsugarcanebyinsilicoanalysisofstemexpressedsequencetagsandgeneexpressionpro?ling.PlantMolBiol54:503–17
21Sugarcane:aMajorSourceofSweetness,Alcohol,andBio-energy507
CasuRE,MannersJM,BonnettGD,JacksonPA,McIntyreCL,etal.(2005)Genomicsapproachesfortheidenti?cationofgenesdeterminingimportanttraitsinsugarcane.FieldCropsRes92:137–147
CasuRE,JarmeyJM,BonnettGD,MannersJM(2007)Identi?cationoftranscriptsassociatedwithcellwallmetabolismanddevelopmentinthestemofsugarcanebyAffymetrixGeneChipsugarcanegenomearrayexpressionpro?ling.FunctIntegrGenomics7:153–167
ChenPH,LinMJ,XueZP,ChenRKA(2004)StudyongenetictransformationofGNAgeneinsugarcane.ActaAgriculturaeUniversitatisJiangxiensis26(5):740–743,748
ChenY,ChenC,LoC(1993)CytogeneticstudiesonSaccharum-Miscanthusnobilisation.Proc7thIntlongreSABRAO:223–233
CuadradoA,AcevedoR,MorenoDiasdelaEspinaS,JouveN,delaTorreC(2004)GenomeremodellinginthreemodernS.of?cinarumxS.spontaneumsugarcanecultivars.JExpBot55:847–854
daSilvaJ,ZorreéisME,BurnquistW,TanksleySD(1993)RFLPlinkagemapandgenomeanalysisofSaccharumspontaneum.Genome36:782–791
daSilvaJA,HoneycuttRJ,BurnquistW,Al-Janabi,SM,SorrellsME,etal.(1995)SaccharumspontaneumL.‘SE208’geneticlinkagemapcombiningRFLP-andCR-basedmarkers.MolBreeding1:165–179
DanielsC(1996)Vol6BiologyandbiologicaltechnologyPartIIIAgro-industriesandforestry.In:NeedhamJ(Editor)ScienceandcivilizationinChina.CambridgeUniversityPress,Cambridge,UnitedKingdom
DanielsJ,DanielsC(1975)Geographical,historicalandculturalaspectoftheoriginoftheIndianandChinesesugarcanesS.barberiandS.sinense.SugarcaneBreedingnewsletter36:4–23
DanielsJ,RoachBT(1987)Taxonomyandevolutioninsugarcane,p7–84.In:HeinzDJ(ed),Sugarcaneimprovementthroughbreeding,ElsevierPress,Amsterdam
DaugroisJH,GrivetL,RoquesD,HoarauJY,LombardH,etal.(1996)AputativemajorgeneforrustresistancelinkedwithaRFLPmarkersinsugarcanecultivar‘R570’.TheorApplGenet92:1059–1064
DeRosaJrVE,NogueiraFTS,MenossiM,UlianEC,ArrudaP(2005)Identi?cationofmethyljasmonateresponsivegenesinsucarcaneusingcDNAarrays.BrazilianJPlantPhysiol17:131–136
DelaneyTP,UknesS,VernooijB,FriedrichL,WeymannK,etal.(1994)Acentralroleofsalicylicacidinplantdiseaseresistance.Science266:1247–1250
D’HontA(2005)UnravellingthegenomestructureofpolyploidsusingFISHandGISH;examplesofsugarcaneandbanana.CytogenetGenomeRes109(1–3):27–33
D’HontA,GlaszmannJC(2001)Sugarcanegenomeanalysiswithmolecularmarkers,a?rstdecadeofresearch.ProcIntSocSugarCaneTechnol24:556–559
D’HontA,LuYH,FeldmannP,GlaszmannJC(1993)Cytoplasmicdiversityinsugarcanerevealedbyheterologousprobes.SugarCane1:12–15
D’HontA,LuYH,GonzàlezdeLeònD,GrivetL,FeldmannP,etal.(1994)Amolecularap-proachtounravelingthegeneticsofsugarcane,acomplexpolyploidoftheAndropogoneaetribe.Genome37:222–230
D’HontA,GrivetL,FeldmannP,RaoPS,BerdingN,etal.(1995)Identi?cationandcharacteriza-tionofsugarcaneintergenerichybrids,Saccharumof?cinarumxErianthusarundinaceus,withmolecularmarkersandDNAinsituhybridization.TheorApplGenet91:320–326
D’HontA,GrivetL,FeldmannP,RaoPS,Berding,N,etal.(1996)Characterisationofthedoublegenomestructureofmodernsugarcanecultivars(Saccharunspp)bymolecularcytogenetics.MolGenGenet250:405–413
D’HontA,IsonD,AlixK,RouxC,GlaszmannJC(1998)DeterminationofbasicchromosomenumbersinthegenusSaccharumbyphysicalmappingofribosomalRNAgenes.Genome41:221–225
D’HontA,PauletF,GlaszmannJC(2002)Oligoclonalinterspeci?coriginof‘NorthIndian’and‘Chinese’sugarcanes.ChromosomeRes10:253–262