Long non-coding RNAs: Fine-tuning the developmental responses in plants.

Plant developmental biology is associated with various gene regulatory pathways involved in different phases of their life cycle. In course of development, growth and differentiation of different organs in plants are regulated by specific sets of gene expression. With the advances in genomic and bioinformatic techniques, particularly high-throughput sequencing technology, many transcriptional units with no protein-coding potential have been discovered. Previously thought to be the dark matters of genome, long non-coding RNAs (lncRNAs) are gradually gaining importance as crucial players in gene regulation during different developmental phases. Some lncRNAs, showing complementarity to microRNAs (miRNAs), are used as endogenous target mimics of specific miRNA family. A number of lncRNAs can also act as natural antisense transcripts to attenuate the expression of coding genes. Although lncRNA-mediated regulations have extensively been studied in animals, plant lncRNA research is still in its initial phase. The present review highlights the regulatory mechanism and different physiological aspects of lncRNAs in plant development. In plants, lncRNAs are found to be associated with a number of plant developmental functions such as lateral root development, vernalization, photomorphogenesis, pollen development, fiber development and nodulation. Understanding these potent roles of lncRNAs in plant development can further provide novel tools for crop improvement programs in future.