Sun Li Ming, Che Jing, Ma Jian Feng, Shen Ren Fang
State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
Plants (Basel). 2021 Mar 26;10(4):634. doi: 10.3390/plants10040634.
Rice is the most aluminum (Al)-tolerant species among the small grain cereals, but there are great variations in the Al tolerance between subspecies, with higher tolerance in subspecies than subspecies. Here, we performed a screening of Al tolerance using 65 cultivars and found that there was also a large genotypic difference in Al tolerance among subspecies. Further characterization of two cultivars contrasting in Al tolerance showed that the expression level of encoding a C2H2-type Zn-finger transcription factor, was higher in an Al-tolerant cultivar, Jinguoyin, than in an Al-sensitive cultivar, Kasalath. Furthermore, a dose-response experiment showed that expression was not induced by Al in both cultivars, but Jinguoyin always showed 5.9 to 11.4-fold higher expression compared with Kasalath, irrespectively of Al concentrations. Among genes regulated by ART1, 19 genes showed higher expression in Jinguoyin than in Kasalath. This is associated with less Al accumulation in the root tip cell wall in Jinguoyin. Sequence comparison of the 2-kb promoter region of revealed the extensive sequence polymorphism between two cultivars. Whole transcriptome analysis with RNA-seq revealed that more genes were up- and downregulated by Al in Kasalath than in Jinguoyin. Taken together, our results suggest that there is a large genotypic variation in Al tolerance in rice and that the different expression level of is responsible for the genotypic difference in the Al tolerance.
水稻是小粒谷物中最耐铝的物种，但不同亚种之间的耐铝性存在很大差异，其中一个亚种的耐受性高于另一个亚种。在这里，我们使用65个品种进行了耐铝性筛选，发现同一亚种内不同品种间的耐铝性也存在很大的基因型差异。对两个耐铝性不同的品种进行进一步表征发现，编码C2H2型锌指转录因子的基因在耐铝品种“金谷银”中的表达水平高于铝敏感品种“卡萨拉斯”。此外，剂量反应实验表明，铝处理并未诱导两个品种中该基因的表达，但无论铝浓度如何，“金谷银”的表达水平始终比“卡萨拉斯”高5.9至11.4倍。在受ART1调控的基因中，有19个基因在“金谷银”中的表达高于“卡萨拉斯”。这与“金谷银”根尖细胞壁中铝积累较少有关。对该基因2-kb启动子区域的序列比较揭示了两个品种之间广泛的序列多态性。RNA-seq全转录组分析表明，与“金谷银”相比，铝处理后“卡萨拉斯”中有更多基因上调和下调。综上所述，我们的结果表明，水稻的耐铝性存在很大的基因型变异，该基因表达水平的差异是耐铝性基因型差异的原因。
