Construction and analysis of EST libraries of the trans-polyisoprene producing plant, Eucommia ulmoides Oliver.
Eucommia ulmoides Oliver is one of a few woody plants capable of producing abundant quantities of trans-polyisoprene rubber in their leaves, barks, and seed coats. One cDNA library each was constructed from its outer stem tissue and inner stem tissue. They comprised a total of 27,752 expressed sequence tags (ESTs) representing 10,520 unigenes made up of 4,302 contigs and 6,218 singletons. Homologues of genes coding for rubber particle membrane proteins that participate in the synthesis of high-molecular poly-isoprene in latex were isolated, as well as those encoding known major latex proteins (MLPs). MLPs extensively shared ESTs, indicating their abundant expression during trans-polyisoprene rubber biosynthesis. The six mevalonate pathway genes which are implicated in the synthesis of isopentenyl diphosphate (IPP), a starting material of poly-isoprene biosynthesis, were isolated, and their role in IPP biosynthesis was confirmed by functional complementation of suitable yeast mutants. Genes encoding five full-length trans-isoprenyl diphosphate synthases were also isolated, and two among those synthesized farnesyl diphosphate from IPP and dimethylallyl diphosphate, an assumed intermediate of rubber biosynthesis. This study should provide a valuable resource for further studies of rubber synthesis in E. ulmoides.
Department of Biotechnology, Graduate School of Engineering, Osaka University, Suita, Osaka, 565-0871, Japan. nosuzuk@bio.eng.osaka-u.ac.jp
Nobuaki
N
Suzuki
Hirotaka
H
Uefuji
Takashi
T
Nishikawa
Yukio
Y
Mukai
Atsushi
A
Yamashita
Masahira
M
Hattori
Naotake
N
Ogasawara
Takeshi
T
Bamba
Ei-ichiro
E
Fukusaki
Akio
A
Kobayashi
Yoshiyuki
Y
Ogata
Nozomu
N
Sakurai
Hideyuki
H
Suzuki
Daisuke
D
Shibata
Yoshihisa
Y
Nakazawa
D019883:Alkyl and Aryl Transferases / Q000235:genetics / Q000378:metabolism; D000595:Amino Acid Sequence; D031283:Eucommiaceae / Q000235:genetics* / Q000378:metabolism*; D020224:Expressed Sequence Tags; D015723:Gene Library; D017343:Genes, Plant; D005816:Genetic Complementation Test; D045782:Hemiterpenes / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D007840:Latex / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation; D009943:Organophosphorus Compounds; D018547:Plant Stems / Q000235:genetics
D045782:Hemiterpenes; D007840:Latex; D009943:Organophosphorus Compounds; C004809:isopentenyl pyrophosphate; C455100:1,4-polyisoprene; D019883:Alkyl and Aryl Transferases