5个毛果杨PtrZFP基因的鉴定和表达分析

Cloning and expression analysis of 5 ZFP genes from Poplus trichocarpa

ZFP转录因子是植物中的一类具有指环结构域的转录因子。从毛果杨中鉴定出5条ZFP基因(命名为PtrZFP1-5),对其特性和表达模式进行了分析,以期初步了解这些基因是否能对胁迫做出应答。对PtrZFP1-5基因进行生物学分析,进一步利用qRT-PCR技术分析NaCl、PEG6000和ABA胁迫处理后毛果杨根、茎和叶中5条基因的表达情况。PtrZFP1-5基因编码蛋白氨基酸残基数为258~338 aa,编码蛋白的分子量为27.7~37.3 kDa,理论等电点为4.87~8.61,5个基因不均等的分布在毛果杨基因组的3条染色体上。qRT-PCR结果显示,0.2 mol·L-1 NaCl、15%(w/v)PEG6000和100μmol·L-1 ABA胁迫处理后,5个PtrZFP基因在毛果杨根、茎和叶中的表达模式明显不同。PtrZFP1基因在3种胁迫后毛果杨中均被明显的上调表达;PtrZFP2基因在盐、渗透和ABA胁迫处理后,叶中的表达都明显被抑制;PtrZFP3基因受到干旱胁迫时在根中的响应最为明显;而叶和茎中,表达量在大部分胁迫的大部分时间点无明显改变。PtrZFP4基因也能在根和茎中对干旱胁迫做出明显应答。PtrZFP5基因在经受盐和ABA胁迫后,在叶中的表达受到明显抑制。PtrZFP1-5这5个基因至少能在一种器官中对一种胁迫处理做出应答,但参与的胁迫应答类型和机制可能不同。

ZFPs are a class of transcription factors in plants that have a loop domain.In this study,5 ZFP genes(named PtrZFP1-5)were identified from Populus trichocarpa,and their sequence characteristics and expression patterns were analyzed to understand the stress response function.The bioinformatics analysis of PtrZFP1-5 gene was carried out,and the expressions of 5 PtrZFP genes in root,stem and leaf of Populus under NaCl,PEG6000 and ABA treatment were further analyzed by qRT-PCR.The number of amino acid residues encoded by PtrZFP1-5 gene was 258-338 aa,the molecular weight of the encoded protein was 27.7-37.3 kDa,and the theoretical isoelectric point was 4.87-8.61.5 PtrZFP genes were unevenly distributed on the three chromosomes of Populus genome.The results of qRT-PCR showed that the expression patterns of 5 PtrZFP genes in roots,stems and leaves of Populus were significantly different after treatment with 0.2M NaCl,15%(w/v)PEG6000or 100μM ABA treatment.The expressions of PtrZFP1 were all up-regulated in three kinds of stresses.The expressions of PtrZFP2 were significantly inhibited in leaves after salt,osmotic and ABA treatment.The expression changed of PtrZFP3 in roots was most obvious under drought stress.In leaves and stems,the expression level did not change significantly at most of the time points of most stress.The PtrZFP4 gene also responded to drought stress in roots and stems.The expression of PtrZFP5 gene in leaves was significantly reduced after exposure to salt and ABA stress.PtrZFP1-5 genes can respond to at least one stress treatment in one organ,but the type and mechanism of the involved stress response may be different.