miR408 is involved in abiotic stress responses in Arabidopsis

Abstract

SUMMARYMicroRNAs (miRNAs) are small RNAs that regulate the expression of target genes post-transcriptionally; they are known to play major roles in development and responses to abiotic stress. miR408 is a highly conserved miRNA in plants that responds to the availability of copper and targets genes encoding copper-containing proteins. It was recently recognized to be an important component of the HY5-SPL7 gene network that mediates a coordinated response to light and copper, illustrating its central role in the response of plants to the environment. Expression of miR408 is significantly affected by a variety of developmental and environmental conditions; however, its biological function is unknown. Involvement of miR408 in the abiotic stress response was investigated in Arabidopsis. Expression of miR408, as well as its target genes, was investigated in response to salinity, cold, oxidative stress, drought and osmotic stress. Analyses of transgenic plants with modulated miR408 expression revealed that higher miR408 expression leads to improved tolerance to salinity, cold and oxidative stress, but enhanced sensitivity to drought and osmotic stress. Cellular antioxidant capacity was enhanced in plants with elevated miR408 expression, as manifested by reduced levels of reactive oxygen species and induced expression of genes associated with antioxidative functions, including Cu/Zn superoxide dismutases (CSD1 and CSD2) and glutathione-S-transferase (GST-U25), as well as auxiliary genes: the copper chaperone CCS1 and the redox stress-associated gene SAP12.Overall, the results demonstrate significant involvement of miR408 in abiotic stress responses, emphasizing the central function of miR408 in plant survival.

The miRNAomes in Rehmannia glutinosa Roots Exposed to Different Levels of Replanting Disease Pressure

“…Many aspects of plant development and their response to stress are regulated by miRNAs (Ma et al, 2015;Niu et al, 2016), reflected by the growing volume of entries deposited in the miRBase 21.0 database. While some hundreds of miRNA sequences have been identified in Arabidopsis thaliana and rice (Reinhart et al, 2002;Gielen et al, 2016), only 37 R. glutinosa ones have been lodged in the database so far Li et al, 2013).…”

Transcriptome Analysis of mRNA and miRNA in Somatic Embryos of Larix leptolepis Subjected to Hydrogen Treatment

“…Plant miRNAs are important regulators in developmental processes and abiotic stress responses [41]. In particular, miR398 and miR408 have been reported to be involved in plant response to oxidative stress and regulating ROS balance [42,43]. Nevertheless, little is known about miRNA profiles in response to H 2 exposure, and their roles during this process remain unclear.…”

Emerging techniques to decipher microRNAs (miRNAs) and their regulatory role in conferring abiotic stress tolerance of plants

“…Recently, a single miRNA was found to confer tolerance to multiple stresses in Arabidopsis. The transgenic lines overexpressing miR408 exhibited improved tolerance to salinity, drought, cold, and oxidative stresses (Ma et al 2015). The transgenic lines under multiple stresses launched an efficient antioxidative system involving up-regulation of CSD1, CSD2, CCS1, glutathione-S-transferase, as well as the redox stress-associated gene, SAP12 (Ma et al 2015).…”

“…The transgenic lines overexpressing miR408 exhibited improved tolerance to salinity, drought, cold, and oxidative stresses (Ma et al 2015). The transgenic lines under multiple stresses launched an efficient antioxidative system involving up-regulation of CSD1, CSD2, CCS1, glutathione-S-transferase, as well as the redox stress-associated gene, SAP12 (Ma et al 2015). Chen et al (2015) described tomato miR396a-5p as a positive regulator of tolerance against multiple abiotic stresses, but a negative regulator of generating resistance against Phytophthora infestans.…”