The discovery of plant-derived MIR167e-5p and its ability to target β-catenin opens new frontiers in cross-kingdom medicine
In a fascinating leap for science, researchers have discovered that plant-derived molecules can directly influence human cellular processes. One such molecule, MIR167e-5p, a microRNA from plants, has been shown to inhibit the proliferation of intestinal cells by targeting a critical protein called β-catenin. This discovery not only challenges our understanding of cross-kingdom communication but also opens new avenues for novel therapeutic strategies in gut health, cancer treatment, and beyond. Imagine a world where eating specific plants could fine-tune your gene expression—this might soon be a reality 1 2 .
Plant microRNAs can survive digestion and directly influence human gene expression, challenging previous assumptions about dietary nucleic acids.
This specific plant microRNA targets β-catenin, a key protein in the Wnt signaling pathway that regulates cell proliferation.
MicroRNAs (miRNAs) are small non-coding RNA molecules, typically 18-24 nucleotides long, that play a pivotal role in regulating gene expression at the post-transcriptional level. They function by binding to complementary messenger RNA (mRNA) sequences, leading to mRNA degradation or translational repression. Both plants and animals produce miRNAs, but there are key differences in their biosynthesis and mechanisms of action 7 :
The concept of cross-kingdom regulation suggests that miRNAs from one species can influence gene expression in another. This phenomenon was first highlighted in 2012 when plant MIR168a was found in human sera and shown to regulate LDLRAP1 in the liver 2 . Since then, numerous studies have demonstrated that diet-derived plant miRNAs can survive harsh gastrointestinal conditions, enter the bloodstream, and modulate human gene expression. This challenges the long-held belief that dietary nucleic acids are fully degraded during digestion 7 .
Plant miRNAs consumed through food can survive digestion, enter the bloodstream, and regulate human genes, representing a novel form of interspecies communication.
Researchers hypothesized that plant miRNAs could serve as exogenous regulators of intestinal cell functions. Using bioinformatic predictions, they identified MIR167e-5p as a potential regulator of β-catenin, a key component of the Wnt signaling pathway that controls cell proliferation, differentiation, and stem cell maintenance. Dysregulation of this pathway is implicated in various cancers and intestinal disorders 1 6 .
Two cell lines were used: IPEC-J2 (porcine jejunum epithelial cells) and Caco-2 (human colon carcinoma cells). Cells were treated with synthetic 2′-O-methylated plant MIR167e-5p at varying doses (0, 10, 20, and 40 pmol) and time points (0, 24, 48, and 72 hours) to assess dose- and time-dependent effects 1 2 .
Cells were transfected using Lipofectamine 2000, with treatments including MIR167e-5p mimics, normal control, MIR167e-5p inhibitor, inhibitor normal control, and combination of MIR167e-5p mimics and inhibitor 1 .
MTT assay and EdU assay were used to measure cell viability and proliferation. Cells were counted at each time point to monitor growth 1 2 .
MIR167e-5p reduces cell viability in a dose-dependent manner. Source: 1
To conduct such experiments, scientists rely on specialized reagents and tools. Here are some essential ones used in studying MIR167e-5p:
| Reagent/Tool | Function Description | Example Use in MIR167e-5p Research |
|---|---|---|
| Lipofectamine 2000 | Transfection reagent for introducing miRNAs into cells. | Delivering synthetic MIR167e-5p into IPEC-J2 and Caco-2 cells 1 . |
| Synthetic 2′-O-methylated miRNAs | Chemically modified miRNAs resistant to degradation. | Mimicking stable plant-derived miRNAs for treatment 1 . |
| Luciferase Reporter Assay | Measures activity of luciferase enzyme linked to target gene UTR. | Validating direct targeting of β-catenin by MIR167e-5p 1 2 . |
| qPCR Probes and Primers | Quantify mRNA levels of target genes. | Assessing expression changes in β-catenin, c-Myc, PCNA 1 . |
| Western Blot Antibodies | Detect specific proteins (e.g., β-catenin, c-Myc). | Confirming protein-level changes post-treatment 1 2 . |
| MTT Assay Kit | Measures cell viability based on metabolic activity. | Determining anti-proliferative effects of MIR167e-5p 1 . |
| EdU Assay Kit | Labels proliferating cells with a thymidine analog. | Visualizing and quantifying cell proliferation 1 . |
The ability of plant MIR167e-5p to modulate the Wnt/β-catenin pathway suggests promising applications in:
Targeting β-catenin could help control cancers driven by aberrant Wnt signaling, such as colorectal cancer.
Regulating intestinal cell proliferation may aid in managing conditions like Crohn's disease or ulcerative colitis.
Developing miRNA-enriched foods or supplements for preventive health 1 .
Interestingly, MIR167e-5p also influences other processes:
Despite the excitement, several challenges remain:
The discovery that plant MIR167e-5p can inhibit enterocyte proliferation by targeting β-catenin is a testament to the incredible potential of cross-kingdom miRNA regulation. This not only deepens our understanding of molecular communication but also paves the way for innovative treatments that harness the power of dietary miRNAs. As research progresses, we may soon see plant-derived miRNAs playing a key role in personalized medicine, offering natural, precise, and effective solutions for a range of diseases. The humble plant, it seems, holds secrets we are only beginning to uncover 1 7 .
This research reveals a sophisticated communication system between plants and humans at the molecular level, suggesting that our relationship with the plant kingdom is far more complex and interactive than previously imagined.