甜菜BvABF基因家族全基因组鉴定及其ABA处理下表达模式分析

Genome-wide identification of the Beta vulgaris ABF(BvABF)gene family and analysis of the expression pattern in sugar beet under ABA treatment

ABA响应元件结合因子(ABRE binding factor,ABF)作为植物中bZIP转录因子的一个独特亚家族,在脱落酸(abscisic acid,ABA)依赖型和非依赖型信号通路中发挥重要作用。为挖掘和鉴定糖料作物甜菜BvABF基因家族生物学功能及其表达模式,本研究采用生物信息学方法,预测了蛋白理化特性、系统进化、染色体位置、基因结构、保守基序、顺式作用元件、二级结构和蛋白互作网络等,并通过qRT-PCR方法分析了在100μmol·L^(-1) ABA处理下BvABF在根和叶中的表达模式。结果表明,从甜菜中鉴定出6个BvABF基因家族成员,将其分为A、B和C簇,它们均含有一个bZIP区域。BvABF分布在1、3、6、7和9号染色体,含有3~4个外显子。BvABF蛋白拥有4个含有潜在磷酸化位点(R-X-X-S/T)的保守区域C1、C2、C3和C4,在C端含有一个碱性区域和4个重复的由亮氨酸(Leu)残基组成的七肽重复序列。BvABF基因家族启动子含有多种激素和光响应元件,其中4个基因含有ABA响应元件(ABA-responsive element,ABRE);另外,干旱诱导的响应元件(MBS)、低温响应元件(LTR)和厌氧响应元件(anaerobic responsive element,ARE)等也存在于该基因家族。此外,BvABF可能与磷酸化相关蛋白(PP2CCNBD-X2、SRK2I、SRK2E-X1和PP2C50)和ABA受体(PYL2、PYL4和PYR1)发生互作。进一步对BvABF在ABA处理下甜菜不同组织中的表达模式分析发现,所有BvABF基因在甜菜根和叶中均受ABA诱导和调控,且不同基因在ABA处理下呈现出不同的表达模式。这些结果表明,BvABFs在糖料作物甜菜响应ABA过程中扮演着重要角色。

Abscisic acid(ABA)-responsive(ABRE)binding factor proteins(ABF)are a unique subfamily of bZIP transcription factor proteins in plants,and play important roles in ABA-dependent and ABA-independent signaling pathways.To explore and identify the biological functions and expression patterns of the BvABF gene family in sugar beet(Beta vulgaris),in the present study,the physicochemical properties,phylogeny,chromosomal localization,gene structure,conserved motifs,cis-acting elements,secondary structure and protein interaction network of BvABFs were predicted by bioinformatics methods,and their expression patterns in roots and leaves of sugar beet under 100μmol·L^(-1) ABA treatments were analyzed by qRT-PCR.A total of six BvABF genes were identified in sugar beet,and divided into groups A,B,and C,all of which contained a bZIP region.The BvABF genes are located on chromosomes 1,3,6,7,and 9,and they contain 3-4 exons.The identified BvABF proteins possess 4 conserved regions,C1,C2,C3,and C4,each containing potential phosphorylation sites(R-X-X-S/T).The C-terminal region contains a basic region and four repeating heptapeptide repeats consisting of leucine residues.The promoter region of BvABFs contained multiple hormone and light responsive elements,with 4 genes containing an ABRE element.In addition,a myeloblastosis(MYB)binding site involved in drought-inducibility(MBS),a low-temperature-responsive element and an anaerobic responsive element were also found among the BvABF genes.Furthermore,BvABF may interact with phosphorylation-related proteins(PP2CCNBD-X2,SRK2I,SRK2E-X1,and PP2C50)and ABA receptors(PYL2,PYL4,and PYR1).The expression patterns of BvABF were further analyzed in different tissues of sugar beet under ABA treatment,and it was found that all the BvABF genes were induced and regulated by ABA both in the roots and leaves,while different gene members exhibited different expression patterns under ABA treatment.These results suggest that BvABFs play important roles in the response of the sugar beet crop to ABA.