MicroRNA (miRNA) in food resources and medicinal plant

Abstract

MicroRNAs (miRNAs) are a class of 19 - 24 nucleotide long non-coding RNAs derived from hairpin precursors, regulating various biological, metabolic and developmental processes at the post-transcriptional level. Many of the known miRNAs are evolutionary conserved across diverse plant species and function in the regulatory control of fundamentally important biological processes. It is known that exogenous plant miRNAs specifically target approximately 30% of protein-coding genes in mammals. The research was focused to analyze the occurrence of selected families of miRNAs (miR156, miR168 and miR171) in less used species but nutritionally important plant food resources (flax and medlar) and medicinal plant (milk thistle). The analyses were done by two individual approaches, by (a) miRNA-based molecular markers - as a novel type of functional markers and (b) qualitative Real-Time PCR. The expression pattern of selected miRNAs was analyzed depending on various plant tissues and developmental stages. Results have confirmed the significance and reliability of novel type of markers based on miRNA molecules as well as the species-specific and tissues-specific expression patterns of plants miRNAs. Significant polymorphism profile of miR156b was detected in various flax tissues of genotypes varying in the content of alpha-linolenic acid. Conclusions indicate that the variable behavior of the miRNA molecules, depending on various factors, may reflect the variability of the gene expression regulation of the human genome.  The exploitation of the background of miRNA functioning within different species and plant tissues will help us to understand the molecular machinery as well as the regulatory mechanisms involved in the expression of miRNAs in plants and consequently in human genome.

Keywords

• miRNA
• human nutrition
• functional food
• medicinal plant