Nuclear factor kappa B subunit RelB (RelB)

Nuclear factor kappa B subunit RelB is one of five members of the NF-κB family of transcription factors, which also includes RelA (p65), c-Rel, NF-κB1 (p50), and NF-κB2 (p52)[4][5][6][7]. RelB contains an N-terminal Rel homology domain (for dimerization, DNA binding, and interaction with inhibitors) and a C-terminal transactivation domain required for gene transcription[1][5][6]. Unlike most NF-κB subunits, RelB cannot form functional homodimers but pairs with p52, especially in the non-canonical (alternative) NF-κB pathway[2]. Upon pathway activation, RelB-containing complexes translocate to the nucleus and regulate the transcription of genes involved in immune responses, inflammation, cell survival, and proliferation[4][5][6][7]. Dysregulation of RelB has been associated with the development and progression of cancers, autoimmune diseases, and chronic inflammatory conditions[6][7]. RelB is considered a therapeutic target mainly in the context of diseases driven by abnormal NF-κB signaling, but there are currently no approved drugs that selectively inhibit RelB in clinical practice[6][7]. Pan-NF-κB pathway inhibitors that act upstream of RelB activation may affect its activity. Ongoing research aims to clarify the specific roles of RelB and to develop more selective modulators for potential therapy.

Other names

RelBNF-κB subunit RelBNF-kappa-B subunit RelBNuclear factor of kappa light polypeptide gene enhancer in B-cells 2RELB

Drugs targeting the NF-κB family generally act by inhibiting pathway activation (e.g., proteasome inhibitors prevent IκB degradation and NF-κB nuclear translocation), but RelB-specific mechanisms have not yet been clinically validated[6][7].