SIGNALING THROUGH THE LEUKOTRIENE B-4 RECEPTOR INVOLVES BOTH ALPHA(I)AND ALPHA(16), BUT NOT ALPHA(Q) OR ALPHA(11) G-PROTEIN SUBUNITS

COS-7 cells transfected with the leukotriene (LT) B-4 receptor (BLTR) cDNA were unable to produce LTB4-induced inositol phosphates (IPs) in spite of the presence of endogenous G alpha(i), G alpha(q) and G alpha (11) proteins. Co-transfection of BLTR with G alpha(16), however, resu lted in high levels of IP production, which were 17-, 10- and 6-fold h igher than with co-transfected G alpha(11), G alpha(q) and G alpha(14) , respectively. Co-transfection of BLTR with phospholipase C (PLC) bet a(2), on the other hand, resulted in efficient IP production and co-tr ansfection of BLTR with both G alpha(16) and PLC beta(2) resulted in a greater than additive response.