RECONSTITUTION OF THE FUNCTIONAL GRANULOCYTE-MACROPHAGE COLONY-STIMULATING FACTOR PROMOTER - EVIDENCE FOR DISTINCT ACTIVATION MECHANISMS THAT MEDIATE THE RESPONSE TO PHORBOL ESTER CALCIUM AND HUMAN T-CELL LEUKEMIA-VIRUS TYPE-I TAX SIGNALS/

Citation
N. Koyanonakagawa et al., RECONSTITUTION OF THE FUNCTIONAL GRANULOCYTE-MACROPHAGE COLONY-STIMULATING FACTOR PROMOTER - EVIDENCE FOR DISTINCT ACTIVATION MECHANISMS THAT MEDIATE THE RESPONSE TO PHORBOL ESTER CALCIUM AND HUMAN T-CELL LEUKEMIA-VIRUS TYPE-I TAX SIGNALS/, International immunology, 5(4), 1993, pp. 345-352
Citations number
33
Journal title
ISSN journal
09538178
Volume
5
Issue
4
Year of publication
1993
Pages
345 - 352
Database
ISI
SICI code
0953-8178(1993)5:4<345:ROTFGC>2.0.ZU;2-Z
Abstract
Functional elements in the promoter region of the mouse granulocyte-ma crophage colony stimulating factor (GM-CSF) gene were assessed by cons tructing chimeric promoters linked to the bacterial chloramphenicol ac etyltransferase (CAT) gene and by employing a transient transfection a ssay of human T cell leukemia Jurkat cells. We previously reported tha t CLE2/GC-box (at positions -95 to -73, which is homologous to the NF- chiB binding site) and CLE0 (at positions -54 to -40) of the mouse GM- CSF promoter are essential for transcriptional activation in response to phorbol-12-myristate-13-acetate (PMA)/calcium ionophore (A23187). H ere we show that CLE2/GC-box and the NF-chiB binding motif are functio nally interchangeable and that CLE2/GC-box and CLE0 as a unit activate the basic GM-CSF promoter in response to PMA/calcium signals. This un it is also capable of activating heterologous promoters in response to PMA/calcium signals. In addition, we show that Tax, the trans-activat or encoded by human T cell leukemia virus type I (HTLV-I), activates t he GM-CSF promoter via CLE2/GC-box without the involvement of CLE0. Th ese results indicate that PMA/A23187-dependent and Tax-dependent activ ation of the GM-CSF gene proceeds through distinct mechanisms.