The RFX complex is crucial for the constitutive and CIITA-mediated transactivation of MHC class I and beta2-microglobulin genes.
In type III bare lymphocyte syndrome (BLS) patients, defects in the RFX protein complex result in a lack of MHC class II and reduced MHC class I cell surface expression. Using type III BLS cell lines, we demonstrate that the RFX subunits RFX5 and RFXAP are crucial for constitutive and CIITA-induced MHC class I and beta2m transactivation. Similar to MHC class II, the promoters of MHC class I and beta2m contain an S-X-Y region of which the X1 box is crucial for constitutive and CIITA-induced MHC class I and beta2m transactivation. Thus, the RFX complex is part of a regulatory pathway linking the transactivation of MHC class I and II and their accessory genes.
Gobin
S J
SJ
Department of Immunohematology and Blood Bank, Leiden University Medical Center, The Netherlands.
Peijnenburg
A
A
van Eggermond
M
M
van Zutphen
M
M
van den Berg
R
R
van den Elsen
P J
PJ
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D017124:Conserved Sequence; D004247:DNA / Q000235:genetics; D015342:DNA Probes / Q000235:genetics; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D005805:Genes, MHC Class I; D005802:Genes, MHC Class II; D006801:Humans; D008969:Molecular Sequence Data; D009687:Nuclear Proteins; D011487:Protein Conformation; D000071701:Regulatory Factor X Transcription Factors; D017386:Sequence Homology, Amino Acid; D016511:Severe Combined Immunodeficiency / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D015534:Trans-Activators / Q000378:metabolism*; D014157:Transcription Factors / Q000737:chemistry / Q000378:metabolism*; D015533:Transcriptional Activation; D014162:Transfection; D001613:beta 2-Microglobulin / Q000235:genetics*
D015342:DNA Probes; D004268:DNA-Binding Proteins; C083728:MHC class II transactivator protein; D009687:Nuclear Proteins; D000071701:Regulatory Factor X Transcription Factors; D015534:Trans-Activators; D014157:Transcription Factors; D001613:beta 2-Microglobulin; D004247:DNA