MicroRNA Regulation in Plant Stress Responses

MicroRNAs (miRNAs) are short (≈21–24 nucleotide) non-coding RNAs that direct post-transcriptional repression of complementary mRNAs, thereby tuning gene expression in response to environmental cues. In plants, miRNA-mediated regulation underpins adaptive responses to both abiotic stressors—such as drought, salinity, temperature extremes and nutrient limitation—and biotic challenges including bacterial, fungal and viral pathogens. Biogenesis of plant miRNAs involves sequential processing by Dicer-like enzymes and loading into Argonaute-containing effector complexes, which then guide cleavage or translational inhibition of target transcripts. Dynamic modulation of specific miRNAs adjusts hormone signalling, reactive oxygen species homeostasis and transcription factor networks to balance growth, development and defence. Certain miRNAs also move systemically through the vasculature, coordinating distal stress responses. Recent technological advances in high-throughput sequencing and spatial profiling are revealing the spatio-temporal complexity of miRNA expression, offering new avenues to engineer resilience through precision breeding or transient, transgene-free interventions.

Research from Nature Portfolio

Recent studies have unveiled a dual-function small RNA module in rice that orchestrates the trade-off between thermotolerance and immune defence. A mutation in SUPPRESSOR OF GENE SILENCING 3a (OsSGS3a) impairs the biogenesis of trans-acting small interfering RNAs (tasiRNAs) targeting AUXIN RESPONSE FACTOR transcripts. Loss of OsSGS3a function reduces heat tolerance yet enhances resistance to bacterial and fungal pathogens, whereas elevated AUXIN RESPONSE FACTOR activity has the opposite effect. This work defines a single small RNA pathway that sets the balance between abiotic and biotic stress responses, providing a blueprint for optimising crop performance under combined stresses.

MicroRNA Regulation in Plant Stress Responses publication trend

The graph below shows the total number of articles in microrna regulation in plant stress responses across all publications each year (not limited to Nature Index journals).

Technical terms

microRNA (miRNA): Small non-coding RNA (~21–24 nt) that guides sequence-specific repression of target mRNAs via cleavage or translational inhibition.

Abiotic stress: Environmental factors such as drought, salinity, temperature extremes or nutrient deficiency that impair plant growth.

Biotic stress: Harmful interactions with living organisms including pathogens and herbivores that trigger plant defence mechanisms.

Trans-acting small interfering RNA (tasiRNA): Secondary small RNAs generated from non-coding transcripts that regulate distinct mRNAs in trans through sequence complementarity and cleavage.

Biogenesis: The multi-step cellular process by which precursor transcripts are processed into mature small RNAs and loaded into effector complexes.

References

1. Plant Small RNAs: Their Biogenesis, Regulatory Roles, and Functions. Annual Review of Plant Biology (2023).
2. The OsSGS3-tasiRNA-OsARF3 module orchestrates abiotic-biotic stress response trade-off in rice. Nature Communications (2023).
3. Transgene-free, virus-based gene silencing in plants by artificial microRNAs derived from minimal precursors. Nucleic Acids Research (2023).
4. Quantitative and spatially resolved detection of multiplexed microRNA from plant tissue via hybridization to hydrogel-bound DNA probes in nanoliter well arrays. Microsystems & Nanoengineering (2024).
5. Diverse set of microRNAs are responsive to powdery mildew infection and heat stress in wheat (Triticum aestivum L.). BMC Plant Biology (2010).