School of Agronomy, Anhui Agricultural University, Anhui province, Hefei, 230036, People's Republic of China.
Biol Res. 2022 Jan 10;55(1):1. doi: 10.1186/s40659-021-00368-w.
Maize (Zea mays L.) is a widely cultivated cereal and has been used as an optimum heavy metal phytoremediation crop. Metallothionein (MT) proteins are small, cysteine-rich, proteins that play important roles in plant growth and development, and the regulation of stress response to heavy metals. However, the MT genes for maize have not been fully analyzed so far.
The putative ZmMT genes were identified by HMMER.The heat map of ZmMT genes spatial expression analysis was generated by using R with the log (FPKM + 1).The expression profiles of ZmMT genes under three kinds of heavy metal stresses were quantified by using qRT-PCR. The metallothionein proteins was aligned using MAFFT and phylogenetic analysis were constructed by ClustalX 2.1. The protein theoretical molecular weight and pI, subcellular localization, TFs binding sites, were predicted using ProtParam, PSORT, PlantTFDB, respectively.
A total of 9 ZmMT genes were identified in the whole genome of maize. The results showed that eight of the nine ZmMT proteins contained one highly conserved metallothio_2 domain, while ZmMT4 contained a Metallothio_PEC domain. All the ZmMT proteins could be classified into three major groups and located on five chromosomes. The ZmMT promoters contain a large number of hormone regulatory elements and hormone-related transcription factor binding sites. The ZmMT genes exhibited spatiotemporal specific expression patterns in 23 tissues of maize development stages and showed the different expression patterns in response to Cu, Cd, and Pb heavy metal stresses.
We identified the 9 ZmMT genes, and explored their conserved motif, tissue expression patterns, evolutionary relationship. The expression profiles of ZmMT genes under three kinds of heavy metal stresses (Cu, Cd, Pb) were analyzed. In summary, the expression of ZmMTs have poteintial to be regulated by hormones. The specific expression of ZmMTs in different tissues of maize and the response to different heavy metal stresses are revealed that the role of MT in plant growth and development, and stress resistance to heavy metals.
玉米（Zea mays L.）是一种广泛种植的谷物，已被用作最佳重金属植物修复作物。金属硫蛋白（MT）蛋白是富含半胱氨酸的小分子蛋白，在植物生长发育和重金属胁迫响应的调控中发挥着重要作用。然而，迄今为止，玉米的 MT 基因尚未得到充分分析。
通过 HMMER 鉴定假定的 ZmMT 基因。使用 R 语言和 log（FPKM + 1）生成 ZmMT 基因空间表达分析的热图。使用 qRT-PCR 定量分析 ZmMT 基因在三种重金属胁迫下的表达谱。使用 MAFFT 对齐金属硫蛋白蛋白，并使用 ClustalX 2.1 构建系统发育分析。使用 ProtParam、PSORT、PlantTFDB 分别预测蛋白质的理论分子量和 pI、亚细胞定位、TFs 结合位点。
在玉米全基因组中鉴定出 9 个 ZmMT 基因。结果表明，9 个 ZmMT 蛋白中有 8 个含有一个高度保守的金属硫蛋白_2 结构域，而 ZmMT4 含有一个 Metallothio_PEC 结构域。所有 ZmMT 蛋白可分为三大类，位于 5 条染色体上。ZmMT 启动子含有大量激素调节元件和与激素相关的转录因子结合位点。ZmMT 基因在玉米发育阶段的 23 种组织中表现出时空特异性表达模式，并对 Cu、Cd 和 Pb 重金属胁迫表现出不同的表达模式。
我们鉴定了 9 个 ZmMT 基因，探索了它们的保守基序、组织表达模式、进化关系。分析了 3 种重金属胁迫（Cu、Cd、Pb）下 ZmMT 基因的表达谱。总之，ZmMTs 的表达可能受到激素的调节。ZmMT 在玉米不同组织中的特异性表达以及对不同重金属胁迫的响应表明 MT 在植物生长发育和对重金属胁迫的抗性中的作用。
