摘要
为了从全基因组和转录组水平鉴定响应盐胁迫的小麦DREB(dehydration responsive element binding,DREB)基因,该研究对小麦耐盐材料CH7034苗期施加盐胁迫后的根部样本进行Illumina转录组测序,从中分离TaDREB家族成员的表达数据和可变剪接信息,并对其下游靶基因进行预测;利用qRT-PCR对盐胁迫响应TaDREB成员和预测靶基因进行验证。结果显示:(1)从小麦中共鉴定出48个DREB成员(204个拷贝序列),命名为TaDREB1~TaDREB48,分布于21条染色体。(2)TaDREB家族分为14组(G1~G14),位于G2、G5、G10和G14的TaDREB成员受NaCl胁迫后转录水平均无显著变化,其余组中共有25个(52%)TaDREB成员表现出对盐胁迫不同程度的响应;其中有9个成员在盐胁迫后持续上调(含5个新报道基因),有2个成员表现为持续下调;蛋白互作预测结果显示,下调成员TaDREB35的编码蛋白可能会受到1个小麦RING型E3泛素连接酶作用而降解。(3)盐胁迫后有9个成员TaDREB3、TaDREB6、TaDREB16、TaDREB19、TaDREB21、TaDREB24、TaDREB25.12、TaDREB43和TaDREB47发生了可变剪切变化。(4)从转录组差异表达基因中进一步鉴定出3个起始密码子上游2000 bp序列,包含DRE/CRT元件且在A/B/D组间表达趋势一致的候选靶基因TaRD29、TaGLOS和TaCKX。(5)qRT-PCR验证结果显示,上调成员中,除TaDREB19外,其余成员以及TaDREB16均表现出持续上升的趋势;下调成员中只有TaDREB25和TaDREB35的表达量呈持续下降的趋势;3个预测靶基因的表达量均持续上升,验证结果与转录组测序结果一致。该研究鉴定出的11个盐胁迫响应TaDREB成员以及预测的3个下游靶基因为小麦耐盐机制解析和分子育种奠定了基础。
In order to identify the dehydration responsive element binding(DREB)genes in response to salt stress from the genome-wide and transcriptome levels in wheat,this study performed transcriptome sequencing on the Illumina platform for roots of a salt-tolerant material CH7034 treated with salt stress at seedling stage,from which information on expression and alternative splicing of the TaDREB family were isolated and their downstream target genes were predicted.Finally,the TaDREBs and predicted targets in response to salt stress were verified by qRT-PCR. The results showed that: (1) 48 DREB members (204 copies) named TaDREB1-TaDREB48 were identified in wheat and distributed on 21 chromosomes. (2) The TaDREB family was divided into 14 groups (G1-G14). The transcription levels of TaDREB mem-bers belonging to G2, G5, G10 and G14 did not change significantly after NaCl stress, while 25 TaDREB members from the rest of the groups showed different degrees of response to salt stress. Among them, 9 members were continuously up-regulated after salt stress (containing 5 new reporter genes), and 2 mem-bers were continuously down-regulated. The protein encoded by the down-regulated member TaDREB35 might be degraded by a wheat RING-type E3 ubiquitin ligase based on the protein interaction prediction re-sult. (3) 9 members, including TaDREB3, TaDREB6, TaDREB16, TaDREB19, TaDREB21, TaDREB24, TaDREB25.12, TaDREB43 and TaDREB47, underwent alternative splicing changes after salt stress. (4) Based on the transcriptome, 3 differentially expressed genes TaRD29, TaGLOS and TaCKX with DRE/CRT elements in 2 000 bp region upstream of their start codon and the same expression trend be-tween A/B/D sub-genomes were selected as candidate targets. (5) qRT-PCR verification results showed that the expression levels of TaDREB16 and the up-regulated members except TaDREB19 displayed con-tinuous upward trend;only TaDREB25 and TaDREB35 among the down-regulated members displayed continuous downward trend;and the expression levels of the three predicted target genes continued to in-crease, which was consistent with the transcriptome sequencing results. The 11 salt stress-responsive TaDREB members and the 3 predicted targets identified in this study will lay the groundwork for the anal-ysis of the salt tolerance mechanism and molecular breeding in wheat.
作者
张蕾
魏爱丽
张晓军
畅志坚
乔麟轶
ZHANG Lei;WEI Aili;ZHANG Xiaojun;CHANG Zhijian;QIAO Linyi(Department of Biology,Taiyuan Normal University,Jinzhong,Shanxi 030619,China;College of Agronomy,Shanxi Agricultural University/Shanxi Key Laboratory of Crop Genetics and Molecular Improvement,Taiyuan 030031,China)
出处
《西北植物学报》
CAS
CSCD
北大核心
2022年第9期1477-1486,共10页
Acta Botanica Boreali-Occidentalia Sinica
基金
山西省基础研究计划青年科学研究项目(20210302124235)
山西省高等学校科技创新项目(2021L439)
山西省回国留学人员科研资助项目(2021-070)
山西农业大学博士科研启动项目(2021BQ39)。
