Quantitative control of MHC class II expression by the transactivator CIITA.
Activation of T lymphocytes is quantitatively controlled by the level of expression of MHC class II molecules. Both constitutive and inducible expression of MHC class II genes is regulated by the transactivator CIITA, which is itself tightly regulated. Since the level of MHC class II molecules expressed is a functionally essential parameter, it was of interest to explore whether MHC class II expression is quantitatively controlled by the level of the transactivator. This report shows that in a variety of experimental conditions one does indeed observe, in both mouse and man, a quantitative control of MHC class II expression by the level of CIITA. This relationship between the regulator gene, which behaves as a rate-limiting factor, and its target genes clarifies our understanding of the quantitative modulation of MHC class II expression, and thus of T lymphocyte activation.
Otten
L A
LA
L. Jeantet Laboratory of Molecular Genetics, Department of Genetics and Microbiology, University of Geneva Medical School, Switzerland.
Steimle
V
V
Bontron
S
S
Mach
B
B
D000818:Animals; D002460:Cell Line; D005786:Gene Expression Regulation / Q000187:drug effects / Q000276:immunology*; D005802:Genes, MHC Class II / Q000187:drug effects; D006367:HeLa Cells; D000949:Histocompatibility Antigens Class II / Q000096:biosynthesis / Q000235:genetics; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D051379:Mice; D008807:Mice, Inbred BALB C; D009687:Nuclear Proteins; D009928:Organ Specificity / Q000235:genetics; D015534:Trans-Activators / Q000096:biosynthesis / Q000502:physiology*
D000949:Histocompatibility Antigens Class II; C083728:MHC class II transactivator protein; D009687:Nuclear Proteins; D015534:Trans-Activators; D007371:Interferon-gamma