Teleost lincRNAs: Functional roles, regulatory mechanisms, and future applications in aquaculture

Long intergenic non-coding RNAs (lincRNAs) regulate gene expression across vertebrate physiological systems, yet their functional roles in teleost fish remain incompletely synthesized. This review systematically integrates current evidence through PRISMA-guided searches across PubMed, Web of Science, and Scopus, identifying ten lincRNA-focused functional studies with genetic, mechanistic, or developmental validation, complemented by twenty two supplementary contextual references. Findings span development, immunity, environmental adaptation, reproduction, regeneration, and toxicology, with each association graded as experimentally validated, bioinformatically predicted, correlational, or speculative. This synthesis offers three core contributions. First, it shows that cis-acting regulation on neighboring genes, mediated through Wnt, NF-κB, and AHR signaling, is the dominant validated lincRNA mechanism across teleost physiological domains. Second, it demonstrates that direct experimental validation, primarily via CRISPR-Cas9 and chromatin-capture assays, remains concentrated in zebrafish, whereas aquaculture-species associations remain largely correlational. Third, it identifies two findings that challenge current lincRNA classification: unexpected regulatory directionality at the slincR-sox9b locus, and micropeptide-encoding potential within annotated lincRNAs. Together, these contributions establish an evidence-graded foundation for future mechanistic studies and translational aquaculture applications.