GSE60583
Genome-wide transcriptomic profiling of ramie (Boehmeria nivea (L.) Gaudich.) in response to cadmium stress
Cadmium (Cd)-contamination in soil has been becoming a major environmental problem in China. Ramie, a fiber crop, was frequently proposed to be used as the crop for phytoremediation of Cd-contaminated farmlands. However, high level Cd accumulation can cause a great inhibition of growth in ramie. To understand the potential mechanism for this phenomenon, the ramie genes involved in the Cd stress response were identified using Illumina pair-end sequencing in two Cd-stressed plants (CdS1 and CdS2) and two control plants (CO1 and CO2) in this study. Approximately 48.7, 51.6, 41.2, and 47.1 million clean sequencing reads generated from the libraries of CO1, CO2, CdS1, and CdS2, respectively, were De novo assembled to yield 56,932 non-redundant unigenes. A total of 26,686 (46.9%) genes were annotated for their function. Comparison of gene expression levels between CO and CdS ramie revealed 155 differentially expressed genes (DEGs). Sixteen DEGs was further confirmed their expression difference by real-time quantitative PCR (qRT-PCR). Among these 16 DEGs, 2 genes encoding GA2-oxidase which is a major enzyme for deactivating bioactive gibberellins (GAs) were found with a markedly up-regulated expression, which is possibly responsible for the growth inhibition of Cd-stressed ramie. Pathway enrichment analysis revealed that a pathway (Cutin, suberine and wax biosynthesis) was markedly enriched by DEGs. The discovery of these Cd stress-responsive genes and pathways will be helpful for further understanding the mechanism of Cd-stressed response and improving the ability of Cd stress tolerance in ramie. Overall design: A total of four samples, two replicates of control plants (CO1 and CO2) and two replicates of cadmium-stressed plants (CdS1 and CdS2) were used for RNA-seq.