Botanical Studies (2006) 47: 111-118.
MOLECULAR BIOLOGY
Gene Investigation into the Inner bark of Taiwania (Taiwania cryptomerioides)
Chen-HsienLEE1,Ming-HsunCHAN2,Ya-NanWANG1,2,andFang-HuaCHU1,*
1 2
School of Forestry and Resource Conservation, National Taiwan University, Taipei, Taiwan Experimental Forest, College of Bio-Resource and Agriculture, National Taiwan University, Taipei, Taiwan
(ReceivedJune23,2005;AcceptedNovember16,2005) ABSTRACT. Taiwania(Taiwania cryptomerioidesHayata)isaconifertreeindigenoustoTaiwanandoneof themosteconomicallyimportantforesttreespeciesontheisland.Morethan100secondarymetaboliteshave beenisolatedfromthisspecies.EssentialoilsandextractsfromTaiwaniapossessmanybioactivities,including antibacterial, antifungal, antitermite, antimite, antioxidiant and antitumor activities. In order to research thosegenesinvolvedinbiochemicalsynthesisandwoodformation,weconstructedacDNAlibraryfromthe inner bark ofTaiwania. Using single-pass sequencing of cDNA clones, 973 expressed sequence tags (ESTs) were generated. A BLASTX search revealed that ESTs related to cell rescue, defense and cell aging were abundantintheinnerbarklibrary,especiallygenesthatrespondtopathogeninfection.Inaddition,homology analysisrevealedthatESTsrelatedtocellwallstructureandsecondarymetabolismrepresentedabout2.3%of the clones. However, 57% of the ESTs from Taiwania showed no significant similarity to any other protein sequencesinthepublicdatabases.ThesesequencesindicatetheuniquenessofTaiwania,anditsconsequently remarkablevalue. Keywords: ExpressedSequenceTags(ESTs);Innerbark;Taiwania(Taiwania cryptomerioidesHayata).
INTRODUCTION
Taiwania(Taiwania cryptomerioidesHayata)isanative species of Taiwan. Along with Ginkgo biloba, Sequoiadendron giganteum and Metasequoia glyptostroboides, TaiwaniaisarelictfromtheTertiaryperiodoftheCenozoicera.ItisindigenoustothecentralpartofTaiwanand lives at altitudes of 1,800~2,600 meters above sea level. It has been planted and flourished at heights as low as 800 meters.Taiwaniaisanimportantspecieseconomicallyas itprovidesgoodqualitywoodforconstruction.Thewood ofTaiwania has good properties, being able to withstand harshweather,bacteriaandtermites.Itisdurableenough forlong-termuse(Wangetal.,1997).Largevolumesof Taiwaniabarkresiduesareprocessedbytheforestindustry.Thebarkcanbeconvertedintofuel,chemicalmaterials, and wood charcoal for various uses. Experiments onthe chemicalcompounds found inTaiwania and other conifers have been conducted for years (Chang et al., 2000a). Many researches have proved that the bioactivity of woodhasacorrelationwiththeextractivesofwood.Essential oils and extractives from Taiwania heartwood, sapwood,andleaveshaveantibacterial,antifungal,antitermite,andantimiteproperties(Changetal.,2000a).Addi* orresponding author: E-mail: fhchu@ntu.edu.tw; Tel: C +886-2-33665261;Fax:+886-2-23654520.

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