m⁶A Regulation in Kidney Fibrosis and the Potential of CRISPR-Based RNA Editing
Gene regulation at the RNA level
A review published in Kidney Research and Clinical Practice summarizes pathways through which N6-methyladenosine (m⁶A) RNA modification contributes to kidney disease and fibrosis, along with therapeutic strategies targeting these pathways. It synthesizes existing mechanistic research and approaches under development rather than demonstrating treatment efficacy in new experiments.
Just as DNA methylation and histone modifications regulate gene expression, chemical marks on RNA also influence gene expression. m⁶A is the most common internal modification in eukaryotic messenger RNA (mRNA). Proteins that install the mark, enzymes that remove it, and proteins that recognize it influence RNA splicing, stability, translation efficiency, and intracellular localization. This regulation centered on RNA modifications is called epitranscriptomic regulation.
However, m⁶A does not always stabilize RNA or worsen disease. Depending on which protein recognizes the mark, the cell type, and the pathological conditions involved, RNA may be maintained or degraded.
m⁶A dysregulation and kidney fibrosis
The prior studies discussed in the review report that changes in m⁶A regulatory machinery are involved in inflammatory and fibrotic pathways in kidney disease. One example is the methyltransferase METTL3, whose expression increases in fibrotic tissue. When a reader protein recognizes m⁶A on a particular transcript, the RNA’s stability or protein production may change, potentially affecting pathological signaling.
Noncoding RNAs (ncRNAs) are also part of this regulatory network. The review discusses cases in which m⁶A-modified ncRNAs connect fibrosis and immune-regulatory pathways. This means that examining only protein-coding RNAs is insufficient to fully explain disease-related regulatory networks.
These findings cannot be assumed to apply in the same direction across all kidney diseases. The review explains that enzymes that remove m⁶A can also play different roles depending on the disease model. Choosing a therapeutic target requires identifying not only whether overall m⁶A levels rise or fall, but also which RNAs in which cells are affected.
Therapeutic potential and delivery limitations
Small-molecule inhibitors that modulate m⁶A pathways and RNA-based therapies are strategies under development. However, systemically inhibiting regulatory machinery that also functions in healthy tissues may pose biological risks. This should be distinguished from off-target effects, in which a drug acts on unintended targets. The gene-deletion examples discussed in the review likewise do not constitute the same evidence as toxicity demonstrated in patients following drug administration.
CRISPR-based epitranscriptome editing is an approach intended to regulate m⁶A on specific RNAs. It involves fusing proteins such as cleavage-inactivated Cas13 to a methyltransferase or demethylase and directing them to a target sequence with guide RNA. The ability to select an RNA sequence does not mean the system can be delivered selectively to kidney tissue. Efficient delivery to renal tubular cells, off-target changes, immunogenicity, and long-term safety remain to be evaluated.
Although m⁶A marks can be regulated reversibly, this does not justify claiming that reversal of established kidney scarring or recovery of lost function has been demonstrated. The review outlines directions for therapeutic development; it does not report evidence confirming the efficacy of editing therapy in patients with kidney disease.
Source: Original review, PubMed citation and abstract.
Source: Epitranscriptomic Regulation in Kidney Disease, 2026.
Summary: Epitranscriptomic regulation, particularly m⁶A RNA methylation, has emerged as a crucial driver of renal pathophysiology. Dysregulation of m⁶A writers, erasers, and readers dynamically alters RNA stability and splicing, exacerbating renal fibrosis and immune responses, partly through m⁶A-modified non-coding RNAs. Emerging therapeutic strategies, notably targeted CRISPR-Cas13-based epitranscriptome editing and small-molecule inhibitors, offer a paradigm shift toward precision medicine, although optimizing tissue-specific delivery and minimizing systemic toxicity remain key challenges.
The practical significance of this review is the need to distinguish enzyme inhibition from regulation of individual RNAs when evaluating candidates for kidney fibrosis treatment. For example, development of a candidate technology that changes m⁶A on a fibrosis-related transcript could include checking changes in the target RNA, whether the technology reaches kidney cells, and how it affects other RNAs and normal tissue function. RNA sequence specificity and tissue delivery each require validation. Because m⁶A regulation also contributes to normal cell function, effects on the target and safety need to be assessed together. The available evidence does not establish that development has reached a stage at which therapeutic benefit in patients or recovery of kidney function can be expected.