| Autor: |
Douhan III, John, Brown, Julia A., Gleit, Zachary L., David, Chella S., Glimcher, Laurie H. |
| Zdroj: |
International Immunology; Feb1996, Vol. 8 Issue 2, p255-265, 11p, 1 Black and White Photograph, 2 Diagrams, 1 Chart, 5 Graphs |
| Abstrakt: |
We have examined the expression and regulation of the MHC class II Eβd gene in both cell lines and in transgenic mice. In transient transfection assays, as little as 192 bp of the Eβd proximal promoter was sufficient to direct constitutive expression of a reporter gene in a B cell line and to confer inducibility by IFN-γ in a macrophage cell line. To determine if the same Eβd promoter sequences were also sufficient to direct correct expression in vivo, Eβd transgenesbearing either 4.1 or 0.2 kb of upstream sequence were introduced into an inbred mouse strain with a non-expressed endogenous Eβ gene. Expression of both transgenes mirrored the expression of the endogenous I-A protein in thymus, B cellsand macrophages with regard to both constitutive and cytokine-inducible expression. These results indicate that for the Eβ gene only 200 bp of proximal promoter sequence are required to achieve tissue-specific and cytokine-inducible expression. This is in striking contrast to the Eα gene, the only other murine class II gene whose promoter has been analyzed in vivo, which has been shown to require 2.0 kb of upstream sequence for appropriate expression. These data demonstrate, therefore, that the location of critical regulatory elements for the Eβ and Eα genes may differ. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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