Scientific article

Functional complementation of major histocompatibility complex class II regulatory mutants by the purified X-box-binding protein RFX

Published inMolecular and cellular biology, vol. 14, no. 10, p. 6839-6847
Publication date1994

Major histocompatibility complex (MHC) class II deficiency, or bare lymphocyte syndrome (BLS), is a disease of gene regulation. Patients with BLS have been classified into at least three complementation groups (A, B, and C) believed to correspond to three distinct MHC class II regulatory genes. The elucidation of the molecular basis for this disease will thus clarify the mechanisms controlling the complex regulation of MHC class II genes. Complementation groups B and C are characterized by a lack of binding of RFX, a nuclear protein that normally binds specifically to the X box cis-acting element present in the promoters of all MHC class II genes. We have now purified RFX to near homogeneity by affinity chromatography. Using an in vitro transcription system based on the HLA-DRA promoter, we show here that extracts from RFX-deficient cells from patients with BLS (BLS cells) in groups B and C, which are transcriptionally inactive in this assay, can be complemented to full transcriptional activity by the purified RFX. As expected, purified RFX also restores a completely normal pattern of X box-binding complexes in these mutant extracts. This provides the first direct functional evidence that RFX is an activator of MHC class II gene transcription and that its absence is indeed responsible for the regulatory defect in MHC class II gene expression in patients with BLS.

  • Base Sequence
  • Cell Nucleus/chemistry/metabolism
  • Cell-Free System
  • DNA-Binding Proteins/genetics/isolation & purification/ metabolism
  • Gene Expression Regulation
  • HLA-DR Antigens/ genetics
  • Humans
  • Immunologic Deficiency Syndromes/etiology/ genetics
  • Lymphocytes/ immunology/pathology
  • Molecular Sequence Data
  • Mutation
  • Promoter Regions, Genetic/ genetics
  • Protein Binding
  • Subcellular Fractions/chemistry/metabolism
  • Transcription Factors/genetics/isolation & purification/ metabolism
  • Transcription, Genetic
Citation (ISO format)
DURAND, Bénédicte et al. Functional complementation of major histocompatibility complex class II regulatory mutants by the purified X-box-binding protein RFX. In: Molecular and cellular biology, 1994, vol. 14, n° 10, p. 6839–6847. doi: 10.1128/mcb.14.10.6839
Main files (1)
ISSN of the journal0270-7306

Technical informations

Creation08/27/2010 1:34:23 PM
First validation08/27/2010 1:34:23 PM
Update time03/14/2023 4:03:08 PM
Status update03/14/2023 4:03:08 PM
Last indexation02/12/2024 7:16:28 PM
All rights reserved by Archive ouverte UNIGE and the University of GenevaunigeBlack