梨叶片黄化复绿过程中bHLH转录因子的表达分析  

Expression Analysis of bHLH Transcription Factor in the Retrieved Leaves of Pear

作　　者：张舒琴 张海燕 于淼 胡小妹 邢杨天 刘伦 ZHANG Shuqin;ZHANG Haiyan;YU Miao;HU Xiaomei;XING Yangtian;LIU Lun*(College of Horticulture,Anhui Agricultural University,Hefei 230036,China)

机构地区：[1]安徽农业大学园艺学院,合肥230036

出　　处：《西北植物学报》2022年第9期1504-1513,共10页Acta Botanica Boreali-Occidentalia Sinica

基　　金：财政部和农业农村部国家现代农业产业技术体系(CARS-28-14)。

摘　　要：为探究bHLH转录因子在梨叶缺铁黄化复绿过程中的表达特性,筛选响应该过程的关键bHLH基因,为改良梨品种抗缺铁能力提供理论依据。该试验以‘砀山酥梨’(Pyrus bretschneideri Rehd.)正常植株和黄化植株为试材,于生长期对黄化植株叶面喷施0.2%FeSO_(4)(2 g/L FeSO_(4))溶液,以清水处理正常植株(N)和黄化植株(C)为对照,取N、C的叶片和幼嫩根毛,以及处理3、6、9和12 d的黄化植株叶片进行转录组学分析,筛选其内差异表达的bHLH基因;采用荧光定量PCR技术,分析叶片和根系中bHLH基因的表达情况、生物学特性以及与叶内Fe^(2+)含量的相关性。结果表明:(1)转录组数据显示,于N、C和FeSO_(4)处理后不同时期黄化叶内共计获得21个表达差异显著的bHLH基因,涉及6个亚族,其motif数1~10不等。(2)qRT-PCR结果显示,C叶内10个基因(PbrbHLH7/29/41/104/119/122/128/155/183/191)的表达量均显著高于N叶内相应基因的表达量,FeSO_(4)处理后其各时期表达量均较C显著下调;而C叶内9个基因(PbrbHLH15/46/53/69/78/89/115/137/144)的表达量均显著低于N叶内相应基因的表达量,FeSO_(4)处理后其各时期表达量均较C显著上调。(3)根与地上部叶的表达水平差异相一致,C根内PbrbHLH29/41/119/128/155/183/191这7个基因的表达量显著高于N根内相应基因的表达量,而C根内PbrbHLH53/89的表达量显著低于N根内相应基因的表达量。(4)相关分析显示,FeSO_(4)溶液处理后各时期内叶片中Fe^(2+)含量与PbrbHLH41表达量呈显著负相关关系,而与PbrbHLH78呈显著正相关关系。研究认为,外源FeSO_(4)处理所调控的梨缺铁黄化叶复绿可能与其所导致的梨叶片样中bHLHs表达量协同变化密切相关;PbrbHLH41/78可能在该过程中发挥着至关重要而拮抗的调控作用,可作为研究梨缺铁黄化复绿机理的候选基因。In order to explore the expression of bHLH transcription factor in the process of iron deficiency retrieved green of pear leaves,we screened the key bHLH genes in response to the process to provide a theoretical basis for improving the iron deficiency resistance of pear varieties.Normal and chlorotic plants of‘Dangshansuli’(Pyrus bretschneideri Rehd.)were taken as test material.We sprayed 0.2%FeSO_(4)(2g·L^(-1) FeSO_(4))solution on the chlorotic leaves and distilled water were used for both normal(N)and chlorotic(C)leaves as control during the growing season.The leaves and tender root hair of normal,chlo-rotic plants and retrieved green leaves on 3rd,6th,9th,12th day after FeSO_(4) application were taken as samples for transcriptome data analysis,and the differentially expressed bHLH genes were screened,sup-plemented by fluorescence quantitative PCR.The expression and biological characteristics of the genes in leaves and roots were analyzed,and the correlation with Fe^(2+) content in leaves were analyzed.The results indicated that:(1)transcriptome data showed that there are 21 bHLH genes were significantly differentially expressed in chlorotic leaves at N,C and different stages after treatment with FeSO_(4),involving 11 subclasses,and their motifs number ranged from 1 to 10.(2)qRT-PCR showed that the expression of PbrbHLH7/29/41/104/119/122/128/155/183/191 in C leaves was significantly higher than that in N leaves.After FeSO_(4) treatment,the expression of them were significantly lower than that in C leaves in different stages;In contrast,the expression of PbrbHLH15/46/53/69/78/89/115/137/144 in C leaves were significantly lower than that in N leaves.After FeSO_(4) treatment,the expression of them were signif-icantly higher than that in C leaves in different stages.(3)Consistent with the difference in the expression level in aboveground leaves,the expression of PbrbHLH29/41/119/128/155/183/191 in C roots were also significantly higher than that in N roots,while the expression of PbrbHLH53/89 in C roots was a

关 键 词：梨 铁 复绿 BHLH 

分 类 号：Q789[生物学—分子生物学] S661.2[农业科学—果树学]