Insights into the Small RNA-Mediated Networks in Response to Abiotic Stress in Plants

Abstract

Under natural conditions, plants are constantly exposed to various environmental stresses such as drought, extreme temperature, salt, UV, mechanical, or nutrient starvation. To cope with these adverse conditions, plants have evolved cascade of molecular networks to perceive and transduce the stress signals, resulting into the reprogramming of gene expression. The stress-regulated reprogramming of gene expression at post-transcriptional regulation has been emphasized with the discovery of small regulatory RNAs. Plant small RNAs represent noncoding RNAs in the size range of 20-24 nucleotides and categorized into hairpin RNAs (hpRNAs) and siRNAs. The fi rst category includes miRNAs, lmiRNAs, and nat-miRNAs while the siRNA group includes hc-siRNA, secondary siRNAs and nat-siRNAs. Studies have shown that small RNAs, especially miRNAs, are dynamically regulated by a variety of abiotic stress conditions. Such sRNAs target a variety of downstream targets including regulatory proteins as well as metabolic enzymes and thus play pivotal role in the regulation of plant abiotic stress response. Stress appears to regulate miRNA biogenesis as well as its activity. Several miRNA gene:target pairs respond to multiple stress conditions and are conserved in various plant species indicating that miRNAs may defi ne pivotal regulatory nodes involved in the regulation of the plant stress response. On the other hand, miRNAs also show variety-/cultivar-specifi c stress response indicating that they themselves are under a very dynamic regulation. The world of small RNAs is gradually unfolding and much remains to be explored, nevertheless, it has been conclusively demonstrated that small RNAs defi ne a new dimension in the molecular regulatory network regulating the plant stress response.

A Multi-Level Iterative Bi-Clustering Method for Discovering miRNA Co-regulation Network of Abiotic Stress Tolerance in Soybeans

“…To explore the biological significance of soybean MTRMs, we collected related soybean miRNAs, which revealed five types of abiotic stresses, involving (1) drought, (2) salt, (3) cold, (4) Pi, (5) phosphorus deficiency based on publications ( Subramanian et al, 2008 ; Kulcheski et al, 2011 ; Li et al, 2011 ; Sha et al, 2012 ; Subramanian, 2012 ; Sunkar et al, 2012 ; Dong et al, 2013 ; Zhang et al, 2014 , 2018 ; Balyan et al, 2015 ; Xu et al, 2016 ; Zheng et al, 2016 ; Chen et al, 2018 ; Gupta et al, 2019 ; Proust et al, 2019 ; Yu J.-Y. et al, 2019 ; Wang et al, 2020 ).…”

Investigations on Regulation of MicroRNAs in Rice Reveal [Ca2+]cyt Signal Transduction Regulated MicroRNAs

“…Additionally, a higher proportion of miRNAs was upregulated by [Ca 2+ ] cyt than downregulated, which is similar to the findings mentioned above. Among the [Ca 2+ ] cyt -responsive miRNAs as well, a big proportion of miRNAs (such as miR156, miR159, miR166, miR167, miR319, and miR396) is also responsive to, at least, one or multiple abiotic stresses, such as cold, drought, salt, UV, and mechanical (Balyan et al, 2015 ).…”

Investigations on regulation of miRNAs in rice reveal [Ca2+]cytsignal transduction regulated miRNAs

“…Additionally, higher proportion of miRNAs was up regulated by [Ca 2+ ] cyt than down regulated which is similar to the findings as mentioned above. Among the [Ca 2+ ] cyt responsive miRNAs as well, a big proportion of miRNAs (such as miR156, miR159, miR166, miR167, miR319, miR396) are also responsive to at least one or multiple abiotic stresses such as cold, drought, salt, UV and mechanical (Balyan et al, 2015).…”