TL;DR
A model in which mRNA modifications act combinatorially to regulate mRNA homeostasis in plants is supported, including advances in profiling technologies, single-base resolution methods, and nanopore direct RNA sequencing.
The molecular mechanisms by which m6A regulates both coding and noncoding RNAs in HCC are summarized, the functional roles of key m6A regulators in hepatocarcinogenesis are highlighted, and the therapeutic potential of targeting the m6A machinery in HCC is discussed.
It is argued that while epitranscriptomics represents a compelling regulatory axis in cancer cell death, advancing the field will require integrative, high-resolution, and functionally precise approaches to move beyond correlative frameworks toward mechanistic and clinically actionable insights.
The maternal-to-zygotic transition (MZT) requires coordinated clearance and deadenylation of maternally deposited mRNAs, yet the underlying molecular mechanisms remain poorly understood. N6-methyladenosine (m6A) has emerged as a key regulator of maternal mRNA fate, but prior studies have relied on population-averaged short-read methods that cannot resolve modification state, poly(A) tail length, or isoform identity on the same molecule. Here, we employ nanopore direct RNA sequencing on zebrafish embryos across MZT to resolve the interplay between m6A deposition, mRNA clearance, and poly(A) tail length dynamics at single-molecule resolution. We find that 78% of expressed maternal genes harbor m6A-modified isoforms, significantly exceeding prior bulk estimates. Within-isoform comparisons demonstrate that m6A promotes mRNA decay, with CDS m6A contributing more to maternal mRNA clearance than 3’-UTR m6A. The positional context of m6A alone is sufficient to determine the temporal regulation of poly(A) tail lengths. CDS m6A constitutively suppresses tail length throughout MZT, while 3′-UTR m6A acquires shortening activity only after zygotic genome activation (ZGA). Transcriptomic analysis of ythdf2 knockout embryos reveals two unrecognized roles. Ythdf2 stabilizes m6A-marked maternal transcripts to set stoichiometry at MZT onset, and is also responsible for maintaining global poly(A) tail homeostasis prior to ZGA through an m6A-independent mechanism. Together, these findings define the single-molecule logic by which m6A modifications shape transcript fate during vertebrate MZT.
N6-methyladenosine (m6A) is a widespread RNA modification that regulates RNA metabolism in eukaryotes, but its distribution and function in bacteria remain poorly defined. Here, we apply GLORI sequencing to generate single-base resolution transcriptome-wide m6A maps in seven bacterial species. We identify 2,845 m6A sites during exponential growth and find extensive condition-dependent methylation dynamics in three strains. In Pseudomonas syringae, m6A remodeling is associated with virulence-related pathways. Comparative analyses reveal 455 conserved m6A site pairs enriched in genes required for growth, energy metabolism, and transmembrane transport. Integrating methylation, transcript abundance, and RNA stability analyses shows that m6A is associated with reduced mRNA abundance and increased RNA stability. We further identify the rRNA methyltransferases RlmF and RlmJ as bacterial mRNA m6A writers. Together, these findings provide a quantitative atlas of bacterial m6A and establish a foundation for understanding its regulatory and evolutionary roles.
This study identifies the direct coordination of translation suppression and transcriptome reprogramming through m6A during the ISR, and shows that mRNA stabilization, not transcription activation, explains much of the transcriptome response during the ISR.
RNA-binding proteins (RBPs) are central regulators of post-transcriptional gene expression, recognizing RNAs through sequence, structure, and chemical modifications. Post-transcriptional RNA modifications, including m6A, m1A, m5C, m7G, and pseudouridine (Ψ), form the epitranscriptome, a dynamic regulatory layer that modulates RNA stability, localization, and translation. These modifications are interpreted by specialized “reader” RBPs that translate epitranscriptomic marks into functional outcomes. Dysregulation of RNA modifications or their associated reader RBPs has been increasingly linked to the development of cancers, neurological disorders, and other diseases, highlighting their potential for therapeutic manipulation. This review summarizes key RNA modifications and regulating RBPs with a specific emphasis on how dysregulation can lead to cancers. We further discuss current approaches for investigating and manipulating reader RBP–RNA interactions, highlighting how these methods enable new opportunities for therapeutic discovery.
