Ancient microRNA families that regulate transcription factors are preferentially preserved during plant radiation

Abstract

Essential genes are usually less likely to be lost during evolution, whereas dispensable genes are lost more frequently. Integrating sacred lotus and other plant microRNA (miRNA) data, we found different ancient miRNA families that arose before eudicot radiation exhibit different evolutionary trajectories. Those ancient miRNA families with higher copy and target numbers, and older age are more likely to be retained in plant descendants and more conserved in (hairpin-structured) miRNA gene sequences. Interestingly, a large portion of the well conserved miRNA families in plant lineages can target transcription factors (TFs). Also, we found miRNA families that target TFs are preferentially retained after sacred lotus genome duplication. In this article, we provide some points to discuss why miRNA families that regulate TFs are more likely to be preserved in plants.

Identification of miRNAs and their target genes in Larix olgensis and verified of differential expression miRNAs

“…In plants, a large proportion of miRNAs and their mRNA target genes have less than four mismatches [14]; thus, plant miRNAs perform their functions mainly through binding to the AGO1 protein to form RISC, cleaving from the middle of the pairing region to the 5 ‘end of mRNA [15, 16]. Numerous previous studies have confirmed that most of the target genes of plant miRNAs are transcription factors, stress response factors, and F-box proteins [17–19], underscoring the central position of miRNAs in the expression and regulation of genes involved in plant development. In addition, studies in recent years have found that plant miRNAs are also involved in signal transduction pathways, plant hormone induction, synthesis and metabolism of organic compounds, and ion transport, indicating the important biological significance of miRNAs.…”