小麦铜转运蛋白基因TaCOPT3响应镉胁迫的功能分析OA
Functional analysis of the wheat copper transporter gene TaCOPT3 in response to cadmium stress
铜转运蛋白(COPT)参与植物金属离子稳态调控,但其在小麦镉(Cd)胁迫应答中的功能尚未明确.基于前期转录组分析发现 TaCOPT3 受 Cd胁迫显著上调,本研究克隆了其 3 个同源拷贝,并系统解析了其序列特征、表达模式及生物学功能.序列分析显示,TaCOPT3-A、TaCOPT3-B、TaCOPT3-D分别编码 162、150 和 162 个氨基酸,均含有保守的Ctr铜转运结构域,与水稻OsCOPT3 序列一致性为 65.40%～68.67%.亚细胞定位预测显示,TaCOPT3 的 3个拷贝均定位于质膜中.启动子区富含ABA、MeJA、SA等激素响应元件及MYB结合位点.RT-qPCR分析显示,Cd胁迫显著诱导3个同源拷贝上调表达,表达量随Cd浓度升高而增加;在300 μmol L-1 CdCl2 处理下,TaCOPT3-A在地上部的表达量较对照上调 427 倍,高于其他拷贝.功能验证表明,在 50 μmol L-1 和 300 μmol L-1 CdCl2 处理下,Ta-COPT3-A突变体 e0483 地上部 Cd积累量较野生型分别显著降低 44.52%和 30.92%,生物富集因子分别降低 36.62%和 24.19%.单倍型分析显示,TaCOPT3-A存在 2 种主要单倍型,其中,单倍型 1 在全球种质中占 63.30%,已知低Cd积累品种济麦 22 属于该单倍型.综上,TaCOPT3 为小麦Cd胁迫响应基因.TaCOPT3-A功能缺失可显著降低地上部Cd积累,提示其参与Cd向地上部的转运调控,该研究为揭示小麦Cd胁迫应答机制提供了理论依据.
Copper transporters(COPT)are involved in maintaining metal ion homeostasis in plants,but their role in the response of wheat to cadmium(Cd)stress remains unclear.Based on previous transcriptome analysis revealing that TaCOPT3 is signifi-cantly upregulated under Cd stress,this study cloned its three homologous copies and systematically analyzed their sequence characteristics,expression patterns,and biological functions.Sequence analysis showed that TaCOPT3-A,TaCOPT3-B,and Ta-COPT3-D encode 162,150,and 162 amino acids,respectively.All contain the conserved Ctr copper transport domain and share 65.40%-68.67%sequence identity with OsCOPT3.Subcellular localization prediction showed that all three copies of TaCOPT3 were localized to the plasma membrane.The promoter regions were rich in hormone-responsive elements(ABA,MeJA,and SA)and MYB transcription factor binding sites.RT-qPCR analysis showed that Cd stress significantly increased the expression of all three TaCOPT3 copies,with levels rising as Cd concentration increased.Under 300 μmol L-1 CdCl2 treatment,the expression level of TaCOPT3-A in the shoot was 427 times higher than that of the control,which was higher than that of other copies.Func-tional analysis showed that under 50 μmol L-1 and 300 μmol L-1 CdCl2 treatment,shoot Cd accumulation in the TaCOPT3-A mu-tant e0483 was significantly reduced by 44.52%and 30.92%,respectively,compared with the wild type,and the bioconcentration factor(BCF)was significantly reduced by 36.62%and 24.19%,respectively.Haplotype analysis showed that TaCOPT3-A could be divided into two main haplotypes,with haplotype 1 accounting for 63.30%of global wheat germplasm.The known low-Cd-accumulating variety Jimai 22 belongs to this haplotype.Taken together,TaCOPT3 is a Cd-responsive gene in wheat.Loss of function of TaCOPT3-A significantly reduces Cd accumulation in shoots,suggesting its role in regulating Cd transport to the aboveground tissues.These findings provide a theoretical basis for unraveling the mechanism of wheat response to Cd stress.
贾康楠;李慧园;郭会君;赵林姝;谢永盾;熊宏春;古佳玉;张玉梅;刘录祥
青岛农业大学农学院,山东 青岛 266109中国农业科学院作物科学研究所/作物基因资源与育种全国重点实验室/作物分子育种国家工程实验室/国家原子能机构核技术(辐射育种)研发中心,北京 100081中国农业科学院作物科学研究所/作物基因资源与育种全国重点实验室/作物分子育种国家工程实验室/国家原子能机构核技术(辐射育种)研发中心,北京 100081中国农业科学院作物科学研究所/作物基因资源与育种全国重点实验室/作物分子育种国家工程实验室/国家原子能机构核技术(辐射育种)研发中心,北京 100081中国农业科学院作物科学研究所/作物基因资源与育种全国重点实验室/作物分子育种国家工程实验室/国家原子能机构核技术(辐射育种)研发中心,北京 100081中国农业科学院作物科学研究所/作物基因资源与育种全国重点实验室/作物分子育种国家工程实验室/国家原子能机构核技术(辐射育种)研发中心,北京 100081中国农业科学院作物科学研究所/作物基因资源与育种全国重点实验室/作物分子育种国家工程实验室/国家原子能机构核技术(辐射育种)研发中心,北京 100081青岛农业大学农学院,山东 青岛 266109中国农业科学院作物科学研究所/作物基因资源与育种全国重点实验室/作物分子育种国家工程实验室/国家原子能机构核技术(辐射育种)研发中心,北京 100081
小麦Cd胁迫TaCOPT3铜转运蛋白突变体单倍型
wheatCd stressTaCOPT3copper transportermutanthaplotype
《作物学报》 2026 (8)
2244-2256,13
本研究由核技术研发科研项目(HJSYF2024(31)),山东省重点研发计划项目(2024LZGCQY001)和北京市"高创计划"青年人才托举工程(20250783)资助.This study was supported by the Nuclear Technology Research and Development Project(HJSYF2024(31)),the Shandong Provincial Key Research and Development Program Project(2024LZGCQY001),and the Young Elite Scientists Sponsorship Program of the Beijing High Innovation Plan(20250783).
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