Lin Kangqi, Yi Ze, Lv Sulian, Zhang Bo, Guo Zijin, Li Yinxin
Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China.
China National Botanical Garden, Beijing, China.
Planta. 2024 Dec 11;261(1):12. doi: 10.1007/s00425-024-04589-7.
1988 lncRNAs were identified in sweet sorghum roots under cadmium treatment; lncRNA 15962 and lncRNA 11558 were validated to be the key lncRNAs involved in regulating cadmium accumulation and translocation. Cadmium (Cd) has become one of the most harmful and widespread pollutants with industry development. Sweet sorghum is an ideal plant for phytoremediation of Cd-contaminated soil. However, little is known about the regulatory role of long non-coding RNAs (lncRNAs) associated with Cd stress response in sweet sorghum. Here, lncRNA-seq was carried out in the roots of two contrasting sweet sorghum genotypes (high-Cd accumulation genotype 'H18', and low-Cd accumulation genotype 'L69'). A total of 1988 lncRNAs were characterized, including 52 and 69 differentially expressed lncRNAs in 'H18' and 'L69' in response to Cd stress, respectively. Furthermore, the trans- or cis-target genes of lncRNAs were investigated. Then, 65 lncRNAs were characterized as the probable target of 117 miRNAs and 1888 genes were identified as putative cis-target genes of Cd-responsive lncRNAs. The dual-luciferase reporter assay indicated lncRNA 15962 may serve as the endogenous target mimics of sbi-miR5565e, which targeted two genes (Sobic.005G212900 and Sobic.009G144700) involved in cell wall metabolism. Four cis-target genes including SbYS1 which encoding a Cd chelate transporter, were up-regulated by overexpression of their corresponding lncRNAs in sweet sorghum protoplasts, suggesting the positive regulatory role of lncRNAs to these cis-target genes. Moreover, the expression of SbYS1 decreased when lncRNA 11558 was inhibited by exogenous miRNA application in 'H18' seedlings, further demonstrating the positive regulatory role of lncRNA 11558 to SbYS1. Altogether, our findings shed light on the regulatory role of lncRNAs associated with Cd accumulation and translocation in sweet sorghum.
在镉处理下的甜高粱根系中鉴定出1988个长链非编码RNA（lncRNA）；lncRNA 15962和lncRNA 11558被证实是参与调节镉积累和转运的关键lncRNA。随着工业发展，镉（Cd）已成为最有害且分布广泛的污染物之一。甜高粱是镉污染土壤植物修复的理想植物。然而，关于甜高粱中与镉胁迫响应相关的长链非编码RNA（lncRNA）的调控作用知之甚少。在此，对两种对比鲜明的甜高粱基因型（高镉积累基因型‘H18’和低镉积累基因型‘L69’）的根系进行了lncRNA测序。共鉴定出1988个lncRNA，其中‘H18’和‘L69’中分别有52个和69个lncRNA在响应镉胁迫时差异表达。此外，还研究了lncRNA的反式或顺式靶基因。然后，65个lncRNA被鉴定为117个miRNA的可能靶标，1888个基因被鉴定为镉响应lncRNA的假定顺式靶基因。双荧光素酶报告基因检测表明lncRNA 15962可能作为sbi-miR5565e的内源性靶标模拟物，sbi-miR5565e靶向两个参与细胞壁代谢的基因（Sobic.005G212900和Sobic.009G144700）。包括编码镉螯合转运蛋白的SbYS1在内的四个顺式靶基因，在甜高粱原生质体中通过其相应lncRNA的过表达而上调，表明lncRNA对这些顺式靶基因具有正向调控作用。此外，在‘H18’幼苗中通过外源miRNA抑制lncRNA 11558时，SbYS1的表达降低，进一步证明了lncRNA 11558对SbYS1的正向调控作用。总之，我们的研究结果揭示了lncRNA在甜高粱镉积累和转运中的调控作用。
