College of Agronomy, Hunan Agricultural University, Changsha 410128, China.
School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan 411201, China.
Genes (Basel). 2022 Dec 17;13(12):2395. doi: 10.3390/genes13122395.
Zinc (Zn)-regulated and iron (Fe)-regulated transporter-like proteins (ZIP) are key players involved in the accumulation of cadmium (Cd) and Zn in plants. X.H. Guo et S.B. Zhou ex L.H. Wu () is a Crassulaceae Cd/Zn hyperaccumulator found in China, but the role of ZIPs in remains largely unexplored. Here, we identified 12 members of family genes by transcriptome analysis in and cloned the gene with functional analysis. The expression of in roots was higher than that in the shoots, and Cd stress significantly decreased its expression in the roots but increased its expression in leaves. Protein sequence characteristics and structural analysis showed that the content of alanine and leucine residues in the SpZIP2 sequence was higher than other residues, and several serine, threonine and tyrosine sites can be phosphorylated. Transmembrane domain analysis showed that SpZIP2 has the classic eight transmembrane regions. The evolutionary analysis found that SpZIP2 is closely related to OsZIP2, followed by AtZIP11, OsZIP1 and AtZIP2. Sequence alignment showed that most of the conserved sequences among these members were located in the transmembrane regions. A further metal sensitivity assay using yeast mutant Δ showed that the expression of increased the sensitivity of the transformants to Cd but failed to change the resistance to Zn. The subsequent ion content determination showed that the expression of increased the accumulation of Cd in yeast. Subcellular localization showed that SpZIP2 was localized to membrane systems, including the plasma membrane and endoplasmic reticulum. The above results indicate that member participates in the uptake and accumulation of Cd into cells and might contribute to Cd hyperaccumulation in .
锌（Zn）和铁（Fe）调节的转运蛋白样蛋白（ZIP）是参与植物中镉（Cd）和 Zn 积累的关键因子。X.H. Guo 等人（）是在中国发现的景天科 Cd/Zn 超积累植物，但 ZIP 在 中的作用在很大程度上仍未被探索。在这里，我们通过对 进行转录组分析，鉴定了 12 个家族基因成员，并克隆了具有功能分析的 基因。 在根部的表达高于在地上部的表达，Cd 胁迫显著降低了根部的表达，但增加了叶片的表达。蛋白序列特征和结构分析表明，SpZIP2 序列中丙氨酸和亮氨酸残基的含量高于其他残基，并且几个丝氨酸、苏氨酸和酪氨酸位点可以被磷酸化。跨膜域分析表明 SpZIP2 具有经典的八个跨膜区域。进化分析发现 SpZIP2 与 OsZIP2 密切相关，其次是 AtZIP11、OsZIP1 和 AtZIP2。序列比对表明，这些成员之间的大多数保守序列都位于跨膜区域。使用酵母突变体 Δ 进行的进一步金属敏感性测定表明， 的表达增加了转化体对 Cd 的敏感性，但未能改变对 Zn 的抗性。随后的离子含量测定表明， 的表达增加了酵母中 Cd 的积累。亚细胞定位表明 SpZIP2 定位于膜系统，包括质膜和内质网。上述结果表明， 成员 参与了 Cd 进入细胞的摄取和积累，可能有助于 在 Cd 超积累中的作用。
