Project Summary/Abstract The idea that long noncoding RNAs (lncRNA) play an important role in regulating gene expression is a quickly growing concept. The lncRNA IFNG-AS1 is found in a multi-cytokine locus which includes IFNG and IL22. IFNG-AS1 has been shown to play an important role for positively regulating the expression of IFNγ expression in both human and mice. Current research concerning the role for Ifng-as1 suggests its role as a positive regulator of Ifnγ, but preliminary data outlined in this grant shows examples of discordant expression of Ifng-as1 and Ifng. This finding suggests an alternative regulation of this lncRNA. The goal of this proposal is to understand the function and regulation of Ifng-as1 under different cellular settings. In Aim 1 we have proposed to define the relationship between Ifng-as1 and the genome under different cellular settings and different cellular states using HiChIRP (i.e. CD4+ T cells and plasma cells). We will also determine what factors are differentially bound to Ifng-as1 through ATAC-seq and ChIP-seq. We will additionally describe a metabolic role for the regulation of Ifng-as1 in particular glycolysis and glutaminolysis through the use of metabolic inhibitors and nutrient supplementation. In Aim 2 we will define proteins bound to Ifng-as1 through RAP-MS and defined the function of Ifng-as1 by deleting Ifng-as1 and its regulatory elements by using CRISPR/Cas9 technology. Finally, we will seek to determine a role for Ifng-as1 in an in vivo setting for ILC3 differentiation and memory development. The findings from this proposed study will provide novel mechanistic information concerning the regulation of Ifng-as1 and Ifnγ providing novel targets for therapeutic intervention.