Microtranscriptome of contrasting sugarcane cultivars in response to aluminum stress

Although metallic elements are required for plant growth, aluminum ions (Al+3) can be considered one of the major abiotic factors affecting productivity. In plants, the presence of Al+3 can result in inhibition of root growth triggering water and nutrient deficiency. Plants under stress conditions undergo gene expression changes in specific genes or post-transcriptional gene regulators as miRNAs that can led to resistance. In this study, we investigated the miRNAs involved in the sugarcane response to aluminum stress. Four miRNA libraries were generated using sugarcane roots of two contrasting (tolerant and sensitive) sugarcane cultivars growing under aluminum stress to identify the miRNAs involved in the sugarcane response. Here we present the first miRNAs sequencing of sugarcane response under aluminum stress. The contrast of the cultivars seen in the field was reflected in the micro transcriptome with opposing expression profile. We selected 394 differentially expressed miRNAs, in both cultivars, 22% were common between cultivars. Real time quantitative polymerase chain reaction was used to validate the differentially expressed miRNAs through high-throughput sequencing in sugarcane roots. Target genes prediction was also analyzed. Our results indicated miRNAs that modulated specific target genes involved in roots development and plant aluminum stress response. Those genes can be the answer to tolerance in sugarcane and used in breeding programs to develop tolerant cultivars.