Identification of zinc responsive miRNAs using high-throughput small RNA sequencing in maize kernel

Zinc (Zn) is an important micronutrient for plants growth and its deficiency affects the normal function of physiological pathways. Development of maize (Zea mays) kernel is a complex process that is associated with the expression of many genes, regulated at transcriptional and post transcriptional level. Micro RNAs (miRNAs) are regulatory molecules that play vital roles in almost all aspects of biological processes. Although several miRNAs have been identified in maize, yet their role in maize kernel development not been studied. Here, we have identified 69 known and 44 novel miRNAs using high-throughput small RNA sequencing of 10 days old baby kernel of high zinc containing maize inbred VQL-2, grown under Zn deficient soil. Among these, 33 known and 35 novel miRNAs were found to be differentially regulated. Gene ontology and KEGG pathway analysis of their targets revealed involvement of several essential pathways such as starch and sucrose metabolism, arginine and proline metabolism. This study provides the valuable information about the role of miRNAs and target networks in response to Zn deficiency in maize kernel.