杨树全基因组 NRAMP 基因家族的鉴定及其作为重金属转运蛋白的功能。

Genome-wide identification of the NRAMP gene family in Populus trichocarpa and their function as heavy metal transporters.

机构信息

State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35 Qinghua East Road, Beijing 100083, China; National Engineering Research Center of Tree Breeding and Ecological Restoration, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China; The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, Beijing Forestry University, Beijing 100083,China.

出版信息

Ecotoxicol Environ Saf. 2023 Aug;261:115110. doi: 10.1016/j.ecoenv.2023.115110. Epub 2023 Jun 8.

DOI:10.1016/j.ecoenv.2023.115110

PMID:37300917

Abstract

The natural resistance-associated macrophage protein (NRAMP) gene family plays a key role in essential mineral nutrient homeostasis, as well as toxic metal accumulation, translocation, and detoxification. Although the NRAMP family genes have been widely identified in various species, they still require to be analyzed comprehensively in tree species. In this study, a total of 11 NRAMP members (PtNRAMP1-11) were identified in Populus trichocarpa, a woody model plant, and further subdivided into three groups based on phylogenetic analysis. Chromosomal location analysis indicated that the PtNRAMP genes were unevenly distributed on six of the 19 Populus chromosomes. Gene expression analysis indicated that the PtNRAMP genes were differentially responsive to metal stress, including iron (Fe) and manganese (Mn) deficiency, as well as Fe, Mn, zinc (Zn), and cadmium (Cd) toxicity. Furthermore, the PtNRAMP gene functions were characterized using a heterologous yeast expression system. The results showed that PtNRAMP1, PtNRAMP2, PtNRAMP4, PtNRAMP9, PtNRAMP10, and PtNRAMP11 displayed the ability to transport Cd into yeast cells. In addition, PtNRAMP1, PtNRAMP6, and PtNRAMP7 complemented the Mn uptake mutant, while PtNRAMP1, PtNRAMP6, PtNRAMP7, and PtNRAMP9 complemented the Fe uptake mutant. In conclusion, our findings revealed the respective functions of PtNRAMPs during metal transport as well as their potential role in micronutrient biofortification and phytoremediation.

摘要

天然抗性相关巨噬细胞蛋白 (NRAMP) 基因家族在必需矿物质营养稳态以及有毒金属的积累、转运和解毒中发挥着关键作用。尽管在许多物种中已经广泛鉴定了 NRAMP 家族基因，但它们仍需要在树种中进行全面分析。在本研究中，在木本模式植物毛白杨中鉴定了 11 个 NRAMP 成员（PtNRAMP1-11），并根据系统发育分析进一步分为三组。染色体定位分析表明，PtNRAMP 基因不均匀分布在 19 条毛白杨染色体中的 6 条上。基因表达分析表明，PtNRAMP 基因对金属胁迫有不同的反应，包括铁（Fe）和锰（Mn）缺乏以及 Fe、Mn、锌（Zn）和镉（Cd）毒性。此外，使用异源酵母表达系统对 PtNRAMP 基因功能进行了表征。结果表明，PtNRAMP1、PtNRAMP2、PtNRAMP4、PtNRAMP9、PtNRAMP10 和 PtNRAMP11 具有将 Cd 转运到酵母细胞的能力。此外，PtNRAMP1、PtNRAMP6 和 PtNRAMP7 互补了 Mn 摄取突变体，而 PtNRAMP1、PtNRAMP6、PtNRAMP7 和 PtNRAMP9 互补了 Fe 摄取突变体。总之，我们的研究结果揭示了 PtNRAMPs 在金属转运过程中的各自功能及其在微量元素生物强化和植物修复中的潜在作用。