Interferons Increase Transcription of a Major Histocompatibility Class I Gene Via a 5′ Interferon Consensus Sequence
Year: 1987
Type: article
Abstract: Interferons (IFNs) augment expression of major histocompatibility class I genes in many cells. To study the effect of IFNs on transcription of class I genes, we prepared and tested activity of chloramphenicol acetyltransferase (CAT) hybrid genes in which the cat gene is under the control of the 5' flanking region of the murine H-2Ld gene. NIH 3T3 cells transiently transfected with a cat construct having the sequence from position -210 to -134 showed a four- to fivefold increase in CAT activity when treated with IFN-alpha/beta. This sequence contains the IFN consensus sequence (ICS) shared among IFN-inducible genes, as well as the class I regulatory element (CRE) that controls up and down regulation of class I gene expression. To determine the precise sequence requirement for the IFN action, the ICS and CRE were independently placed upstream of the class I or a heterologous simian virus 40 promoter, and CAT activity was tested. The ICS, but not the CRE, enhanced activity of both promoters by about twofold upon exposure to IFN-alpha/beta, although greater responses were noted when the ICS and CRE were combined. These results demonstrate that the ICS alone is capable of enhancing promoter activity in response to IFN-alpha/beta treatment and that the CRE exerts a synergistic effect. Further, we show that the ICS functions as an inducible enhancer since it acts regardless of its orientation and distance in the simian virus 40 promoter.
Source: Molecular and Cellular Biology
DOI: 10.1128/mcb.7.7.2625
Authors: K Sugita, J Miyazaki, E Appella, K Ozato
Language: English
Subfield: Immunology
Field: Immunology and Microbiology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2147243389