Cloning and Expression Analysis of HbERFB4-1 Gene in Hevea brasiliensi

Based on EST sequences from an ethephon-induced latex SSH cDNA library of Hevea brasiliensis,a full-length cDNA encoding AP2/ERF type gene named as HbERFB4-1,was cloned from H.brasiliensis by RACE-PCR.The HbERFB4-1 cDNA has full length of 732 bp with an open reading frame(ORF) of 444 bp,and encodes 147 amino acid residues.No introns were detected in HbERFB4-1gene.The deduced HbERFB4-1 contains an AP2 domain and three NISs,which shows high identity to AP2/ERF in Populus trichocarpa,Ricinus communis,Arabidopsis thaliana and Glycine max,counting for 78%、71%、62% and 55%,respectively.Phyogenetic analysis showed that HbERFB4-1 belonged to the B4 subfamily of ERF family.Semi-quantitative RT-PCR analysis indicated that the transcription of HbERFB4-1 in latex was low,but it was rapidly induced by ethephon,suggesting that HbERFB4-1 is involved in the ethylene signal pathway in latex of H.brasiliensis.