Abstract：2C-methyl-D-erythritol 2, 4-cyclodiphosphate synthase (MCS) is the fifth enzyme of the nonmevalonate terpenoid pathway for isopentenyl diphosphate biosynthesis and is involved in the methylerythritol phosphate (MEP) pathway. A MCS gene was isolated from Hevea brasiliensis by RT-PCR and RACE based on the conserved sequences of plant MCS genes. The cDNA, which designated HbMCS1, consists of 965 bp and encodes a protein of 241 amino acids with a predicted molecular mass of 25.82 kDa. In comparison, this putative HbMCS1 protein shows from 62.2% to 70.8 % identity to other plants MCS. Semi-quantitative RT-PCR analysis indicates that the HbMCS1 is more highly expressed in callius than in latex and leaves. The transcription of HbMCS1 in latex was induced tapping, whereas ethylene had little effect. The present study contributes towards an understanding of the biosynthetic mechanism of natural rubber in Hevea brasiliensis.
