CIS-ACTING DNA ELEMENTS OF MOUSE GRANULOCYTE-MACROPHAGE COLONY-STIMULATING FACTOR GENE RESPONSIVE TO FC-EPSILON RECEPTOR CROSS-LINKING STIMULATION IN THE MOUSE MAST-CELL LINE MC 9/

Mouse mast cells produce many kinds of cytokines in response to cross- linking of high affinity Fc epsilon receptor (Fc epsilon RI). Among th ese cytokines, granulocyte-macrophage CSF (GM-CSF) gene induction in m ouse mast cells has been reported to be regulated at both the transcri ptional level and the post-transcriptional level. We analyzed the mech anism of the transcriptional regulation of GM-CSF gene induction throu gh Fc epsilon RI cross-linking stimulation in the mouse mast cell line MC/9. In MC/9, the GM-CSF gene was activated transcriptionally by Fc epsilon RI cross-linking stimulation. The 5' deletion analysis of GM-C SF gene promoter indicated that the 5' boundary of the responsive prom oter region lay between positions -113 and -95. When the deletion was extended to positions -72 or -60, the stimulatory effect was significa ntly diminished. We then examined 3' deletion of pmGMCAT-113 from posi tion -60. This analysis indicated that the 3' boundary lay between pos itions -84 and -72. No subfragments of the region spanning positions - 113 to -72 could cover the full induction level. A site-directed mutag enesis experiment revealed that the sequence spanning positions -108 t o -72 was needed for full activation. These data indicate that GM-CSF gene in mast cells is activated mainly through the sequence spanning p ositions -108 to -72.