Cloning and characterization of HsfA2 from Lily (Lilium longiflorum).
Heat shock transcription factors (Hsfs) are the terminal components of the signal transduction chain mediating the activation of genes responsive to both heat stress and a large number of chemical stressors. This paper aims to clone Hsf from lily and characterize its function by analyses of mRNA expression, transactivation activity and thermotolerance of transgenic Arabidopsis. In this study, the gene encoding HsfA2 with 1,053 bp open reading frame (ORF) was cloned by rapid amplification of cDNA ends (RACE) technique from Lilium longiflorum 'White heaven'. Multiple alignment and phylogenetic analyses showed that the deduced protein was a novel member of the Hsf class A2. Expression analyses by RT-PCR indicated that LlHsfA2 expression was induced by heat shock and H(2)O(2) treatment, but not by NaCl. It was also found that the expression of LlHsfA2 correlated with thermotolerance in Lilium longiflorum 'White heaven' and Oriental hybrid 'Acapulco' under heat stress. Furthermore, yeast one-hybrid assay showed that LlHsfA2 had transactivation activity. In addition, overexpression of LlHsfA2 activated the downstream genes including Hsp101, Hsp70, Hsp25.3 and Apx2 and enhanced the thermotolerance of transgenic Arabidopsis plants. Taken together, our data suggest that LlHsfA2 is a novel and functional HsfA2, involved in heat signaling pathway in lily and useful for improvement of thermotolerance in transgenic plants.
Xin
Haibo
H
Department of Ornamental Horticulture and Landscape Architecture, China Agricultural University, 2 Yuanmingyuan Xilu, Beijing 100193, People's Republic of China.
Zhang
Hua
H
Chen
Li
L
Li
Xiaoxin
X
Lian
Qinglong
Q
Yuan
Xue
X
Hu
Xiaoyan
X
Cao
Li
L
He
Xiuli
X
Yi
Mingfang
M
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D029681:Arabidopsis Proteins; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D000076249:Heat Shock Transcription Factors; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D006358:Hot Temperature; D006861:Hydrogen Peroxide / Q000494:pharmacology; D027762:Lilium / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics; D016415:Sequence Alignment; D012965:Sodium Chloride / Q000494:pharmacology; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation
D029681:Arabidopsis Proteins; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; C000620134:HSFA2 protein, Arabidopsis; D000076249:Heat Shock Transcription Factors; D006360:Heat-Shock Proteins; D010940:Plant Proteins; D018749:RNA, Plant; D014157:Transcription Factors; D012965:Sodium Chloride; D006861:Hydrogen Peroxide