Regulatory factor X associated protein (RFXAP)

Regulatory factor X associated protein (RFXAP) is a transcription factor and coactivator within the RFX complex that binds to the X-box motif in the promoters of MHC class II genes and is required for their transcriptional activation[1][2][3][4]. The RFX complex, which includes RFXAP, RFXANK, and RFX5, enables the expression of MHC class II molecules, which are critical for antigen presentation and activation of the adaptive immune response via T cells[1][2][4]. Mutations in the RFXAP gene can cause bare lymphocyte syndrome type II, a rare but severe immunodeficiency disease[1][3][4]. While RFXAP itself is not a direct drug target, its role in immune modulation makes its pathway of interest for therapeutics aimed at altering MHC class II expression[4].

Other names

RFX associated proteinMHC2D4

Not directly targeted; biological mechanisms involve transcriptional activation of MHC class II genes via the RFX complex