Premium
In vivo , RFX5 binds differently to the human leucocyte antigen‐E, ‐F, and ‐G gene promoters and participates in HLA class I protein expression in a cell type‐dependent manner
Author(s) -
Rousseau Philippe,
Masternak Krzysztof,
Krawczyk Michal,
Reith Walter,
Dausset Jean,
Carosella Edgardo D.,
Moreau Philippe
Publication year - 2004
Publication title -
immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.297
H-Index - 133
eISSN - 1365-2567
pISSN - 0019-2805
DOI - 10.1111/j.1365-2567.2004.01783.x
Subject(s) - ciita , human leukocyte antigen , hla g , biology , chromatin immunoprecipitation , promoter , major histocompatibility complex , microbiology and biotechnology , genetics , mhc class ii , gene , gene expression , antigen
Summary We analysed the regulation of human leucocyte antigen (HLA)‐E, ‐F and ‐G genes, focusing on the SXY module, a promoter region that controls major histocompatibility complex (MHC) class II expression and participates in the expression of classical HLA class I molecules. It comprises the X1, X2 and Y boxes, bound by RFX, X2‐BP/ATF/CREB and NFY factors, respectively. The complex recruits the master control factor CIITA. The SXY module is conserved in HLA‐E and HLA‐F gene promoters, whereas in the HLA‐G promoter, the only conserved boxes are S and X1. Chromatin immunoprecipitation assays, performed on HLA‐G positive and negative cell lines, demonstrated the in situ binding of RFX5 and CIITA to HLA‐E and HLA‐F , but not to HLA‐G , promoters. In B cells from bare lymphocyte syndrome patients lacking RFX5 or CIITA, we observed lower steady‐state levels of HLA‐E and HLA‐F transcripts but did not find any significant decrease in the cell‐surface expression of HLA‐E/classical HLA class I. In RFX5‐deficient fibroblasts, the cell‐surface expression of HLA molecules was decreased. RFX5 and CIITA are thus not involved in HLA‐G expression and their importance for the surface expression of HLA‐E/classical HLA class I molecules may vary depending on the cell type.