Integrated transcriptomics and miRNAomics provide insights into the regulatory networks associated with coleoptile senescence in rice.

Purpose: To understand the miRNAome changes during coleoptile senescence, small RNA libraries were constructed from control and senescence tissues and subjected to Illumina sequencing. Methods: Rice seeds were surface sterilized and submerged for seven days in sterile water. The seeds with coleoptile was transferred to aerobic condition. Senescence progression was monitored and tissues of un-senesced and senesced coleoptiles were harvested. Total RNA was isolated from the harvested tissues. Total four small RNA libraries of coleoptile senescence were constructed and high-throughput sequencing was performed using Illumina GA IIx system . . Results: Small RNA sequencing identified forty-one known and twenty-one novel miRNAs that were differentially expressed during coleoptile senescence. Integration of expression data of transcriptome and miRNAome identified 148 miRNA-mRNA modules, mainly comprised of miRNAs regulating TFs, signaling-associated factors and transporters, thereby demonstrating multi-tiered regulation of coleoptile senescence. Conclusions: The present study has generated a comprehensive resource of the molecular networks that enrich our understanding of the fundamental pathways regulating coleoptile senescence in rice. miRNAomic profile of coleoptile senescence in rice.