Identification of miRNAs and their target genes associated with improved corn seed vigor induced by gibberellin (GA3) through small RNAs and degradome sequencing

Background: High seed vigor is crucial for agricultural production owing to its potential in high quality and yield of crops. A better understanding of the underlying mechanisms is highly necessary. Results: To better understand the involvement and regulatory mechanism of miRNAs correlated with maize seed vigor, small RNAs and degradome sequencing of two inbred lines Yu537A and Yu82 were performed. A total of 791 mature miRNAs were obtained with different expressions, among of which 505 miRNAs were newly identified and the rest miRNAs were more or less reported before by comparing the miRNAs with the sequences in miRbase database. Analysis of miRNA families showed maize seeds contain fewer miRNA families and larger miRNA families compared with animals, indicating that functions of miRNAs in maize seeds were more synergistic than animals. Degradome sequencing was used to identify the targets of miRNAs and the results showed a total of 6196 targets were obtained. Function analysis of di?erentially expressed miRNAs and targets showed Glycan degradation and galactose metabolism were closely correlated with improved corn seed vigor. Conclusions: These findings provide valuable information to understand the involvement of miRNAs with corn seed vigor and these putative genes will be valuable resources for improving the seed vigor in future corn breeding. Overall design: A total of 18 samples were sequenced with 3 biological replicates per group. Please note that "S" represents the late germination variety YU537A, "E" represents the early germination cultivar YU82, 6h, 53h, and 78h represent the time of germination, and "SGA_53h" represents the late germination variety YU537A treated with GA to germinate at 53h after imbibition.