Sjp. Gobin et al., THE RFX COMPLEX IS CRUCIAL FOR THE CONSTITUTIVE AND CIITA-MEDIATED TRANSACTIVATION OF MHC CLASS-I AND BETA(2)-MICROGLOBULIN GENES, Immunity (Cambridge, Mass.), 9(4), 1998, pp. 531-541
In type III bare lymphocyte syndrome (BLS) patients, defects in the RF
X protein complex result in a lack of MHC class II and reduced MHC cla
ss I cell surface expression. Using type III BLS cell lines, we demons
trate that the RFX subunits RFX5 and RFXAP are crucial for constitutiv
e and CIITA-induced MHC class I and beta(2)m transactivation. Similar
to MHC class II, the promoters of MHC class I and beta(2)m contain lan
S-X-Y region of which the X1 box is crucial for constitutive and CIIT
A-induced MHC class I and beta(2)m transactivation. Thus, the RFX comp
lex is part of a regulatory pathway linking the transactivation of MHC
class I and II and their accessory genes.