A cDNA clone encoding a vacuolar H+-pyrophosphatase (V-H+-PPase) was isolated from Hordeum brevisubulatum (Trin.) Link by using RACE method. Sequence analysis revealed that HbVP1 contained 2 319 nucleotides of open reading frame (ORF) and 420 nucleotides of 3′-untranslated region. Its encoding protein consisted of 773 amino acid residues, which includes 14 transmembrane helices. The predicated molecular mass is 80.4 kDa with pI of 4.90. The V-H+-PPases in higher plants shared low identity (40-55%) with those of protozoa, marine alga and archaebacteria. HbVP1 transcripts accumulated abundantly in roots, shoots and seeds, and it was also strongly induced by salt treatment.
【目的】克隆强抗寒性牧草——短芒大麦DREB1(dehydration responsive element binding protein 1)转录因子,分析其生理生化特性,为理想抗逆工程基因的筛选和利用奠定理论基础。【方法】利用RACE-PCR(Rapidamplification of cDNAends-polymerase chain reaction)技术分离短芒大麦DREB1转录因子全长cDNA序列,North-ern杂交和凝胶滞留试验分析其在逆境条件下的表达情况,及其与DRE(dehydration responsive element)元件的结合活性。【结果】从强抗寒性短芒大麦中成功分离了1个新的DREB1类转录因子HbDREB1,该基因全长899 bp,其蛋白序列中含有1个典型的AP2/EREBP DNA结构域及"PKK/RPAGRxKFxETRHP"和"DSAWR"、"LWSY"3个DREB1特征标签序列;序列比对分析表明,HbDREB1与其他植物的DREB1类转录因子的同源性较高。HbDREB1在转录水平上明显受冷胁迫诱导表达,具有结合DRE-顺式作用元件的功能及作为转录因子必备的核定位特性。【结论】HbDREB1基因参与了非生物胁迫信号转导,具有提高植物抗寒性的潜能。
[目的]研究强抗寒性牧草——短芒大麦DREB1(dehydration responsive element binding protein1)基因的功能,为理想抗逆工程基因的筛选和利用奠定理论基础。[方法]利用农杆菌介导法转化烟草叶盘,对转基因烟草进行分子生物学鉴定,并对离子渗漏率、脯氨酸表达量生理生化特性进行测定。[结果]HbDREB1整合入烟草基因组,已在转录水平上表达,转基因烟草在冷胁迫条件下的离子渗漏率明显低于对照组,且其脯氨酸表达量明显增高。[结论]HbDREB1基因具有提高植物抗寒性的潜能。