Lee Sang-Beom, Kim Gyeong-Jin, Kim Kyu-Won, Chu Sang-Ho, Shin Jung-Du, Lee Yu-Ji, Park Yong-Jin, Park Sang-Won
Chemical Safety Division, National Institute of Agriculture Science (NIAS), Wanju, 55365, South Korea.
Department of Plant Resources, College of Industrial Sciences, Kongju National University, Yesan, 32439, South Korea.
Rice (N Y). 2019 Nov 21;12(1):84. doi: 10.1186/s12284-019-0340-8.
Rice is a major food resource for Asian countries including Korea. However, most Asian countries are facing food safety problems due to cropland contamination by heavy metals. Thus, this study was conducted to investigate genetic factors affecting the expression of cadmium (Cd) gene, and to confirm differences in Cd translocation among cultivars because the current molecular understanding of Cd uptake-transport mechanisms remains insufficient. Associations between genotypes and gene expression level of Cd-related genes such as NRAMP, MTP, and HMA gene families in the rice core collection were analyzed at the genomic level.
Os01g0956700, Os05g0128400 and Os11g0485200 showed strong associations between expression level and genotype in the rice core collection, the regulatory factors that associated with these genes in cis and trans were founded. The association between the expression level and genotype of the candidate gene (Os01g0611300: metal tolerance protein) predicted to affect Cd content in rice by a previous genome-wide association study (GWAS) was also analyzed. Furthermore, as a result of the phylogeny and haplotype analyses of the candidate gene, high-Cd tolerance cultivars were selected. The correlations between Cd and other inorganic components (Mg, Mn, Fe, Cu and Zn) in the roots, stems, leaves and unpolished grain of selected rice cultivars were analyzed.
Therefore, these results may be useful for understanding the uptake-transport mechanisms of Cd and other inorganic components via molecular genetics and may help rice breeders develop new low-Cd cultivars in the near future.
水稻是包括韩国在内的亚洲国家的主要食物来源。然而，由于重金属对农田的污染，大多数亚洲国家正面临食品安全问题。因此，本研究旨在调查影响镉（Cd）基因表达的遗传因素，并确认不同品种间Cd转运的差异，因为目前对Cd吸收 - 转运机制的分子理解仍然不足。在基因组水平上分析了水稻核心种质中与Cd相关基因（如NRAMP、MTP和HMA基因家族）的基因型与基因表达水平之间的关联。
在水稻核心种质中，Os01g0956700、Os05g0128400和Os11g0485200在表达水平与基因型之间表现出强关联，发现了与这些基因顺式和反式相关的调控因子。还分析了先前全基因组关联研究（GWAS）预测的影响水稻Cd含量的候选基因（Os01g0611300：金属耐受蛋白）的表达水平与基因型之间的关联。此外，通过对候选基因的系统发育和单倍型分析，筛选出了高Cd耐受性品种。分析了所选水稻品种的根、茎、叶和糙米中Cd与其他无机成分（Mg、Mn、Fe、Cu和Zn）之间的相关性。
因此，这些结果可能有助于通过分子遗传学理解Cd和其他无机成分的吸收 - 转运机制，并可能有助于水稻育种者在不久的将来培育出新的低Cd品种。
