000 02219nam a2200229Ia 4500
008 220216s9999 xx 000 0 und d
100 _aKim In Jeong
245 2 _aA Novel cDNA from Parthenium argentatum gray enhances the rubber biosynthetic activity in vitro
260 _bJournal of Experimental Botany
_c2004
300 _a377-385
520 _aNatural rubber (cis-1,4-polyisoprene) is an isoprenoid compound produced exclusively in plants by the action of rubber transferase. Despite a keen interest in revealing the mechanisms of rubber chain elongation and chain length determination, the molecular nature of rubber transferase has not yet been identified. A recent report has revealed that a 24 kDa protein tightly associated with the small rubber particles of Hevea brasiliensis, therefore designated small rubber particle protein (SRPP), plays a positive role in rubber biosynthesis. Since guayule (Parthenium argentatum gray) produces natural rubber similar in size to H. brasiliensis, it is of critical interest to investigate whether guayule contains a similar protein to the SRPP. A cDNA clone has been isolated in guayule that shares a sequence homology with the SRPP, thus designated guayule homologue of SRPP (GHS), and the catalytic function of the protein was characterized. Sequence analysis revealed that the GHS is highly homologous in several conserved regions to the SRPP (50;identity). In vitro functional analysis of the recombinant protein overexpressed in E.coli revealed that the GHS plays a positive role in isopentenyl diphosphate incorporation into high molecular weight rubbers as SRPP does. These results indicate that guayule and Hevea rubber trees contain a protein that is similar in its amino acid sequence and plays a role in isopentenyl diphosphate incorporation in vitro, implying that it contributes to the enhancement of rubber biosynthetic activity in rubber trees.
650 _aGuayule
650 _aHevea brasiliensis
650 _aIDP incorporation
650 _aParthenium argentatum
650 _aRubber biosynthesis
650 _aRubber particle protein
700 _aKang Hunseung
700 _aKwak Yeon Sig
700 _aRyu Stephen B
942 _cJS
999 _c53482
_d53482