Integration of miRNA and mRNA analysis reveals the role of ribosome in to anti-artificial aging in sweetcorn

Sweetcorn is a kind of maize with high sugar content and has poor seed aging tolerance, which seriously limits its production. However, few studies have explored the artificial aging (AA) tolerance by miRNA-mRNA integration analysis in sweetcorn. Here, we characterized the physiological, biochemical and transcriptomic changes of two contrasting lines K62 and K107 treated with AA during time series. Both the germination indexes and antioxidant enzymes showed significant difference between two lines. The MDA content of AA-tolerant genotype K62 was significantly lower than that of K107 on the fourth and sixth day. Subsequently, 157 differentially expressed miRNAs (DEMIs) and 8878 differentially expressed mRNAs (DEMs) were identified by RNA-seq analysis under aging stress. The "ribosome" and "peroxisome" pathways were enriched to respond to aging stress, genes for both large units and small ribosomal subunits were significantly upregulated expressed and higher translation efficiency might exist in K62. Thirteen pairs of miRNA-target genes were obtained, and 8 miRNA-mRNA pairs might involve in ribosome protein and translation process. Our results elucidate the mechanism of sweetcorn response to AA at miRNA-mRNA level, and provide a new insight into sweetcorn AA response to stress.