Cloning and characterization of pre-miR159a and pre-miR1123 from Indian hexaploid wheat and their evolutionary linkage analysis

Abstract

MicroRNAs (miRNAs) are important post-transcriptional regulator of genes in plants. In spite of their unusual small size (-21-24 nt), the evolutionary history of miRNA gene families appears to be similar to their protein-coding counterparts. Although many miRNA genes are conserved across the plant species, the same gene family varies significantly in size and genomic organization in different species. In the present study, we characterized Tae pre-miR159a (Triticum aestivum precursor-miR159a) and Tae pre-miR1123 from a most popular Indian wheat cultivar Agra local. miR159a is conserved across the species while miR1123 is reported in wheat. Sequence analysis of the pre-miR159a among different plant species suggest conserved motif in duplex miRNAs. Beside mature miRNAs, certain other regions are also found to be conserved across species which might be the site of processing of the precursors by DCL1. Sequence identity matrix suggests 43-82% variation in precursor of Tae AL pre-miR159a (Tae Agra local pre-miR159a) across the species. On the other hand, Tae AL pre-miR1123 (Tae Agra local pre-miR1123) showed >83% sequence similarity with the reported sequence of Tae pre-miR1123. Sequence similarity of precursor and matured miRNA across the species suggests the common evolutionary point from the same gene family which is essential for the processing and stem loop structure of the precursor miRNAs.

Keywords:  Cloning, stem-loop structure, sequence comparison, duplex, precursor

African Journal of Biotechnology, Vol 13(31), 3150-3157