Slfn2, also known as Schlafen 2, is a cytoplasmic protein involved in multiple biological processes. It plays a crucial role in T cell-mediated immunity, type I interferon responses, and the regulation of cell quiescence. Associated pathways include those related to oxidative stress response in T cells, NF-κB signaling in the context of interferon responses, and cholesterol and lipid homeostasis in maintaining cell quiescence. Genetic mouse models, such as the elektra mouse with a Slfn2 mutation, have been valuable in studying its functions [1,2,3,4,5].

In T cells, Slfn2 deficiency leads to the accumulation of tRNA fragments due to stress-induced cleavage, inhibiting translation and promoting stress-granule formation. This renders T cells insensitive to interleukin-2's mitogenic effects, highlighting its importance in T cell expansion and immunity [1]. In the context of interferon responses, targeted disruption of Slfn2 leads to increased transcription of IFN-stimulated genes and enhanced type I IFN-mediated antiviral responses by modulating the NF-κB pathway [2]. In the elektra mouse model, Slfn2 mutation causes lymphoid and myeloid immunodeficiency due to loss of immune cell quiescence, and also disrupts cholesterol and lipid homeostasis in T cells and monocytes [3,4]. Moreover, in T-cell acute lymphoblastic leukemia (T-ALL), targeting Slfn2 to disrupt T-cell quiescence can prevent disease development and progression [6]. In osteoclastogenesis, Slfn2 is a positive regulator, and its loss-of-function in mice results in an osteopetrotic phenotype [7,8].

In conclusion, Slfn2 is essential for T cell-mediated immunity, the regulation of type I interferon responses, and the maintenance of cell quiescence in various cell types. The study of Slfn2 using gene knockout (KO) mouse models, like the elektra model, has provided valuable insights into its role in diseases such as immunodeficiency, T-ALL, and osteopetrosis. Understanding Slfn2 functions may offer new therapeutic strategies for these diseases.