Aluminum triggers broad changes in microRNA expression in rice roots

Abstract

ABSTRACT. MicroRNAs are small 21-nucleotide RNA molecules with regulatory roles in development and in response to stress. Expression of some plant miRNAs has been specifically associated with responses to abiotic stresses caused by cold, light, iron, and copper ions. In acid soils, aluminum solubility increases, thereby causing severe damage to plants. Although physiological aspects of aluminum toxicity in plants have been well characterized, the molecular mediators are not fully elucidated. There have been no reports about miRNA responses to aluminum stress. Modulation of miRNA expression may constitute a key element to explain the mechanisms implicated in aluminum toxicity and tolerance. We examined the expression of at least one miRNA member from each miRNA family in rice roots of Oryza sativa spp indica cv. Embrapa Taim and Oryza sativa spp japonica cv. Nipponbare under high concentrations of aluminum. Forty-six miRNA families were effectively detected by quantitative PCR. Among these, 13 were down-regulated and six were up-regulated in roots of the Nipponbare cultivar after 8 h of aluminum treatment. In roots of the Embrapa Taim cultivar, five miRNAs were down-regulated and three were upregulated. Analyses of their putative targets suggest that these rice miRNAs are involved in the regulation of various metabolic pathways in response to high concentrations of aluminum.

Molecular Identification and Analysis of Arsenite Stress-Responsive miRNAs in Rice

“…To overcome such toxicity, plants have evolved various strategies to adapt to environmental stresses. Previous research revealed that the regulatory mechanisms of plants in response to stresses are complex, and many miRNA genes function in the processes of stress 65,66 whereas >60 miRNAs were found to be involved in the process of arsenite response in this study (see the Supporting Information). Seven family members including miR1318, miR1861, miR2121, miR810, miR812, miR815, and miR818 were significantly down-regulated after the treatment of arsenite.…”

A Novel Gene, OZONE-RESPONSIVE APOPLASTIC PROTEIN1, Enhances Cell Death in Ozone Stress in Rice

“…MicroRNA was quantified according to Lima et al (2011). Total RNA was reverse transcribed using M-MLV Reverse Tramscriptase (Promega).…”

Proteomic Identification of Putative MicroRNA394 Target Genes in Arabidopsis thaliana Identifies Major Latex Protein Family Members Critical for Normal Development

“…The importance of F-box proteins to plant growth and development is further evidenced by the expression of several F-boxencoding genes under additional post-transcriptional regulation by a class of small regulatory nonprotein-coding RNAs, termed microRNAs (miRNAs). A number of molecular approaches have shown that the expression levels of F-box protein encoding genes, Transport Inhibitor Response 1 (TIR1), Leaf Curling Responsiveness (LCR) and More Axillary Growth 2 (MAX2) are regulated via miR393-, miR394-, and miR528-directed mRNA-cleavage, respectively (12)(13)(14).…”