关键词: 蜡梅, 胚胎晚期丰富蛋白, 原核表达, 基因表达分析

Abstract: CpLEA，a new late embryogenesis abundant protein（LEA）gene was identified by randomly cloning and sequencing from Chimonanthus praecox flowers cDNA library. CpLEA has an open reading frame（ORF）of 273 bp encoding a putative 91aa-polypeptide，with two introns of 35 bp and 707 bp respectively. The bioinformatics analysis showed that there were no signal peptide and trans-membrane domain existing in CpLEA protein. Phylogenetic analysis indicated that CpLEA protein can be clustered together with the other known plant group 3 LEA proteins according to its sequence characterizations. Then， the prokaryotic expression vector，which contained the ORF of CpLEA gene，was constructed and the targeted fusion protein at the molecular weight 30 kD coding by CpLEA gene was induced by IPTG. qRT-PCR demonstrated that expression of CpLEA was higher in mature seed compared to that in other tissues and was almost cannot be observed in roots. During the flowering stage，the expression of CpLEA was abundant in the early stage of the flower development and then decreased until the blooming stage and increased significantly at the scence senescence stage. The expression of CpLEA was up-regulated by ABA，cold，salt，drought and hot stresses. It can be to some extent inferred that the CpLEA gene obtained in this study plays an important role in early stage of flower development and abiotic stresses responses.

Key words: Chimonanthus praecox, late embryogenesis abundant protein（LEA）, prokaryotic expression, gene expression analysis