Differential transcription elements direct expression of HLA-DQ genes.

Regulation of class II MHC gene expression, including the HLA-DQ genes, is primarily at the level of transcription. Locus-specific control of DQ gene transcription is both tissue-specific and developmentally regulated and relies on complex mechanisms involving specific DNA-protein interactions. Electrophoretic mobility shift and DNase I protection assays demonstrate the presence of unique nuclear protein interactions with the consensus W and Y box elements in the DQB1 promoter region in DQ-negative cell lines. Based on these and other recent studies, a multistage model of DQ gene regulation is outlined to account for specific patterns of DQ gene expression.