MicroRNAs (miRNAs) are major post-transcriptional regulators of gene expression. Their biogenesis relies on the cleavage of longer precursors by a nuclear localized processing machinery. The evolutionary preference of plant miRNAs to silence transcription factors turned these small molecules into key actors during growth and adaptive responses. Furthermore, during their life cycle plants are subject to changes in the environmental conditions surrounding them. In order to face these changes, plants display unique adaptive capacities based on an enormous developmental plasticity, where miRNAs play central roles. Many individual miRNAs have been shown to modulate the plant response to different environmental cues and stresses. In the last few years, increasing evidence has shown that not only individual genes encoding miRNAs but also the miRNA pathway as a whole is subject to regulation in response to external stimulus. In this review, we discuss the current knowledge about the miRNA pathway. We dissect the pathway to analyze the events leading to the generation of these small RNAs and emphasize the regulation of core components of the miRNA biogenesis machinery.
Bibliographical noteFunding Information:
We thank the Argentinean Society of Biochemistry and Molecular Biology Research (SAIB), in which this review was conceived at the LIV annual meeting, and The Plant Journal for financial support of that event. P.A.M and J.F.P are funded by grants from ANPCyT (Agencia Nacional de Promoci?n Cient?fica y Tecnol?gica, Argentina), HFSP (Human Frontier Science Program), the Max Planck Society and ICGEB (International Centre for Genetic Engineering and Biotechnology). P.A.M. and J.F.P are members of CONICET. This research is also supported by the Basic Science Research Program through the National Research?Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (NRF-2017R1A2B4010255 and 2018R1A6A1A03025607). We also thank Agustin Arce for his critical reading of this review.
All Science Journal Classification (ASJC) codes
- Plant Science
- Cell Biology