Research Projects

MicroRNAs are small (20-24 nucleotides) non-coding regulatory RNAs having numerous roles in plant growth and development including biotic and abiotic stresses. Wheat is an important food crop globally and its cultivation is severely affected by leaf rust diseases, which is difficult to control. In our previous studies using NGS of small RNA and degradome libraries prepared from wheat near-isogenic lines after 72 hours post infection, we could identify several leaf rust responsive miRNAs and their target genes. In this proposed study we aim to perform Dual RNA sequencing to comprehensively identify novel as well as conserved interacting microRNAs of host (wheat) and microRNA-like miRNAs of the biotrophic fungal pathogen (Puccinia triticina) at different timepoints post infection. The target genes of those miRNAs will be deciphered through degradome sequencing and validated through RLM-RACE. Whether any cross-kingdom activity of the wheat or pathogen derived microRNAs/microRNA-like RNAs will also be investigated. It has been found in recent studies that the precursor miRNAs contain several open reading frames and the first ORF at 5´ end encodes small regulatory peptides (miPEPs) that control the biosynthesis and expression levels of the microRNAs derived from it and thereby regulating the expression of target genes. In our preliminary study a few such miPEPs were detected from precursor sequences using bioinformatic tools. Two such microRNAs exclusively originating in the resistant near-isogenic line were sequenced, but detail characterization including the characterization of the recombinant peptide remains to be done.