Decoding the interplay between QKI and m7G methylation on 3'UTR

About This Grant

PROJECT SUMMARY Post-transcriptional regulation is a critical mechanism controlling cellular differentiation and development, driven by coordinated interactions between RNA-binding proteins (RBPs) and RNA modifications. This proposal investigates the interplay between Quaking (QKI) isoforms and N7-methylguanosine (m7G) RNA modifications. QKI isoforms exhibit distinct subcellular localizations and functions, yet their roles in binding m7G-modified transcripts at 3′ untranslated regions (UTRs) during differentiation remain poorly understood. The central hypothesis is that QKI isoforms regulate differentiation by binding m7G-modified mRNAs at 3′ UTRs, with cytoplasmic QKI6 stabilizing transcripts essential for myeloid differentiation. Furthermore, m7G modifications may independently regulate gene expression in ways yet to be defined. Our preliminary evidence demonstrates that cytoplasmic QKI isoforms mediate myeloid differentiation, highlighting a critical gap in understanding m7G’s functional roles in steady-state cellular processes. Current methods for detecting m7G methylation at single- nucleotide resolution face technical limitations. This project addresses these challenges by employing direct RNA long-read sequencing and orthogonal methods to map m7G modifications with precision and identify QKI isoform-specific mRNA targets. Integrating these approaches will elucidate how QKI-m7G interactions influence myeloid differentiation, with broader implications for RNA modifications in stem cell biology, neurodevelopment, and cancer. Over the next five years, the laboratory’s mission is to (1) develop novel methods for base-resolution m7G detection, (2) define mRNA targets regulated by distinct QKI isoforms, and (3) determine the functional impact of QKI-m7G interactions on myeloid differentiation. These studies will advance understanding of RNA modification-driven gene regulation and may inform therapeutic strategies for diseases such as leukemia. By resolving the interplay between QKI and m7G at 3′UTRs, this work will reveal how their coordination regulates cellular functions across human cell types, directly addressing NIGMS’s mission to support foundational discovery science. The proposed research will provide mechanistic insights into RNA modifications dysregulated in cancer, potentially uncovering new targets for therapeutic intervention in malignancies and developmental disorders.