Zhi Shuai, Zou Wenli, Li Jinyan, Meng Lijun, Liu Jindong, Chen Jingguang, Ye Guoyou
School of Agriculture, Sun Yat-sen University, Shenzhen, China.
CAAS-IRRI Joint Laboratory for Genomics-Assisted Germplasm Enhancement, Agricultural Genomics Institute in Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China.
Front Plant Sci. 2023 Feb 23;14:1131064. doi: 10.3389/fpls.2023.1131064. eCollection 2023.
Magnesium (Mg) is an essential element for plant growth and development. Rice is an important food crop in the world, but there are few studies on the uptake and translocation of Mg in rice. We used a multi-parent advanced generation inter-cross (MAGIC) population constructed using four parental lines and genotyped by a 55 K rice SNP array for association analysis to locate QTLs related to Mg uptake and translocation in rice at the seedling stage. Four QTLs ( and ) were detected for the root Mg concentration, which explained 11.45-13.08% of the phenotypic variation. The Mg transporter gene, , was within the region of . Three QTLs ( and ) were detected for the shoot Mg concentration, which explained 4.30-5.46% of the phenotypic variation. Two QTLs ( and ) were found to affect the translocation of Mg from the roots to the shoots, and explained 10.91% and 9.63% of phenotypic variation. and might be the same, since they are very close to each other on chromosome 3. Analysis of candidate genes in the region of and through qRT-PCR, complementation assay in the yeast Mg transport-defective mutant CM66, and sequence analysis of the parental lines suggested that may play important roles in Mg uptake, translocation and accumulation in rice. Overexpression of can significantly increase the Mg concentration in rice seedlings, especially under the condition of low Mg supply.
镁（Mg）是植物生长发育所必需的元素。水稻是世界上重要的粮食作物，但关于水稻中镁的吸收和转运的研究较少。我们使用由四个亲本系构建的多亲本高级世代杂交（MAGIC）群体，并通过55K水稻SNP阵列进行基因分型，以进行关联分析，从而定位水稻幼苗期与镁吸收和转运相关的QTL。检测到四个与根镁浓度相关的QTL（和），它们解释了11.45 - 13.08%的表型变异。镁转运蛋白基因位于的区域内。检测到三个与地上部镁浓度相关的QTL（和），它们解释了4.30 - 5.46%的表型变异。发现两个QTL（和）影响镁从根到地上部的转运，分别解释了10.91%和9.63%的表型变异。和可能是相同的，因为它们在3号染色体上彼此非常接近。通过qRT-PCR分析和区域内的候选基因、在酵母镁转运缺陷突变体CM66中进行互补试验以及对亲本系进行序列分析表明，可能在水稻镁的吸收、转运和积累中起重要作用。过表达可以显著提高水稻幼苗中的镁浓度，尤其是在低镁供应条件下。
