The ‘how’ and ‘where’ of plant microRNAs

Abstract

Contents 1002I.1002II.1007III.1010IV.10131013References1013 Summary MicroRNAs (miRNAs) are small non‐coding RNAs, of typically 20–24 nt, that regulate gene expression post‐transcriptionally through sequence complementarity. Since the identification of the first miRNA, lin‐4, in the nematode Caenorhabditis elegans in 1993, thousands of miRNAs have been discovered in animals and plants, and their regulatory roles in numerous biological processes have been uncovered. In plants, research efforts have established the major molecular framework of miRNA biogenesis and modes of action, and are beginning to elucidate the mechanisms of miRNA degradation. Studies have implicated restricted and surprising subcellular locations in which miRNA biogenesis or activity takes place. In this article, we summarize the current knowledge on how plant miRNAs are made and degraded, and how they repress target gene expression. We discuss not only the players involved in these processes, but also the subcellular sites in which these processes are known or implicated to take place. We hope to raise awareness that the cell biology of miRNAs holds the key to a full understanding of these enigmatic molecules.

Keep calm and carry on: miRNA biogenesis under stress

“…In plants, DICER‐LIKE 1 (DCL1) and accessory proteins such as hyponastic leaves 1 (HYL1) and serrate (SE) process these precursors to release the actual miRNAs, which are in turn loaded to an argonaute (AGO) protein, usually AGO1. Mature miRNAs of around 21 nt pair to longer RNAs and guide them to cleavage or translational arrest (reviewed in Rogers and Chen, ; Yu et al ., ). Many evolutionarily conserved miRNAs regulate transcription factors involved in plant development and hormone signaling, and thus impairing the function of general components of the miRNA pathway causes strong developmental and growth defects.…”

Genome‐wide analysis of coding and non‐coding RNA reveals a conserved miR164‐NAC regulatory pathway for fruit ripening

“…The miRNAs are a class of noncoding short RNAs (19-24 nt) which take part in post-transcriptional regulation by inhibiting translation or cleaving targeted messenger RNAs (mRNAs) (Yu et al, 2017). The miRNAs are a class of noncoding short RNAs (19-24 nt) which take part in post-transcriptional regulation by inhibiting translation or cleaving targeted messenger RNAs (mRNAs) (Yu et al, 2017).…”

Prediction and Characterization of miRNA/Target Pairs in Non‐Model Plants Using RNA‐seq

“…Background on miRNA biogenesis and function miRNAs are non-coding RNAs of ß20 to 24 nt that regulate post-transcriptional gene expression of targets (reviewed in Yu, Jia, & Chen, 2017). As shown in Figure 9, miRNA biogenesis begins with transcription of a MIR gene by RNA polymerase II to produce a primary miRNA (pri-miRNA), consisting of a stem-loop region flanked by unstructured arms.…”