The functionally conserved human lncRNA motif GULF lowers glucose and lipid levels in obese mice.

Growing evidence links human long noncoding RNAs (lncRNAs) to metabolic disease pathogenesis, yet no FDA-approved drugs target human lncRNAs. Most human lncRNAs lack conservation in other mammals, complicating efforts to define their roles and identify therapeutic targets. Here, we leveraged the concept of functionally conserved lncRNAs (FCLs) - lncRNAs that share function despite no sequence similarity - to develop a framework for identifying human lncRNAs as therapeutic targets for metabolic disorders. We used expression quantitative trait loci mapping and functional conservation analyses to pinpoint human lncRNAs influenced by disease-associated SNPs and with potential functionally conserved mouse equivalents. We identified human and mouse GULLs (glucose and lipid lowering), which regulate glucose and lipid metabolism by binding CRTC2, thereby modulating gluconeogenic genes via CREB and lipogenic genes via SREBP1. Despite their lack of sequence similarity, both lncRNAs demonstrated similar metabolic effects in obese mice, with more pronounced benefits from long-term activation. To identify druggable sites, we mapped GULLs' binding motifs to CRTC2 (termed GULFs). Standalone human GULF, an RNA oligomer resembling FDA-approved siRNAs, significantly improved glucose and lipid levels in obese mice. This framework highlights functionally conserved human lncRNAs as promising therapeutic targets, exemplified by GULLs' potential as a glucose- and lipid-lowering therapeutic.