Cloning and molecular characterization of HbCOI1 from Hevea brasiliensis.

The full-length cDNA encoding a coronatine insensitive-1 (COI1) protein, designated HbCOI1, was isolated for the first time from Hevea brasiliensis by the rapid amplification of cDNA ends (RACE) method. HbCOI1 contained a 2,187 bp open reading frame encoding 597 amino acids. The deduced HbCOI1 protein, which showed high identity to COI1 protein of other plant species, was predicted to possess F-box and LRRs domains. The promoter region of HbCOI1 was isolated by the PCR-based DNA walking method. TATA box and other core configurations were found in the promoter. Several sequences similar to the eukaryotic cis regulatory element were found in the 5'-untranslated region (UTR) proximal 5' flanking sequence of HbCOI1. Southern blot analysis indicated that the HbCOI1 is present as a single copy in Hevea brasiliensis. Transcription pattern analysis revealed that HbCOI1 had high transcription in laticifer, low in barks and leaf. Transcription of HbCOI1 in latex was induced by jasmonate and tapping.