Epigenetic and Post-Translational Regulation of Schlafen Family Expression and Their Differential Methods of Regulating Proteins.

Schlafen (SLFN) proteins are a unique and emerging yet incompletely understood family that have primarily been investigated for their putative roles in immunological responses, cell proliferation, and non-malignant cell differentiation. Increasingly, SLFNs have been implicated in diverse biological and pathological contexts, including cancers, viral replication, embryonic lethality, meiotic drive, and inflammatory bowel diseases, where they may be either genetically upregulated or downregulated. In recent years, novel insights into their functional similarities and distinctive particularities have intensified interest in this gene family. This review critically evaluates the biology of SLFN proteins with a specific focus on the epigenetic regulation of their expression and the differential methods by which they regulate downstream proteins. Evidence indicates that SLFNs act not only as regulators of transcription but also as modulators of gene expression through post-transcriptional modifications and epigenetic mechanisms, which demonstrate their multifaceted and context-dependent activity across disease models. By consolidating these findings, this review brings to light the physiological and pathological significance of SLFNs and identifies key gaps in understanding their epigenetic control and mechanistic diversity, thereby offering directions for future research.