cRel-GFP adenovirus

c-Rel is a member of the NF-κB/Rel transcription factor family, which also includes RelA (p65), RelB, c-Rel, and the precursor proteins NF-κB1 (p105/p50) and NF-κB2 (p100/p52). Like other family members, c-Rel contains an N-terminal Rel homology domain (RHD) that mediates its DNA binding to κB motifs, dimerization with other NF-κB subunits, and interaction with inhibitory IκB proteins, which retain c-Rel in the cytoplasm in the resting state. Its C-terminal transcriptional activation domain confers strong gene activation capabilities, which are particularly important in immune cells. c-Rel plays a central role in the activation, differentiation, proliferation, and survival of T and B cells; it controls the expression of cytokines and co-stimulatory molecules, including genes involved in Th1 polarization and B cell maturation. Upon stimulation by antigen receptors, Toll-like receptors, or cytokine receptors, upstream kinases trigger IκB degradation, allowing c-Rel-containing dimers to translocate to the nucleus and drive the transcription of target genes. Genetic and functional studies have shown that dysregulation of c-Rel activity is associated with autoimmunity and inflammation, while hyperactivity or amplification of the REL gene is linked to certain B-cell lymphomas.

The cRel-GFP adenovirus vector, based on human adenovirus type 5 (E1/E3 deleted) and containing a CMV promoter, provides a versatile tool for studying the biological functions of c-Rel in different cellular contexts. The dE1/E3 backbone makes the vector replication-deficient and non-integrating into the genome, thus supporting transient, high-level transgene expression without genomic insertion; meanwhile, the CMV promoter provides strong and broad transcriptional activity in many mammalian cell types. Expression of mouse c-Rel can be used for gain-of-function studies, rescue experiments in a c-Rel-deficient background, and cross-species mechanistic comparisons. Co-expression of GFP facilitates convenient visualization, tracking of transduced cells, and rapid assessment of expression levels. This vector is ideally suited for mapping c-Rel-dependent transcriptional programs through overexpression combined with transcriptomics or chromatin-based analyses, dissecting NF-κB pathway networks through perturbation and epistasis analyses, and screening for small molecules or biologics that modulate c-Rel function in a pathway-selective manner.