FIGURE 4.

Human MBOATs 5 and 7 show arachidonoyl-CoA selectivity and thimerosal sensitivity. An acyl-CoA substrate choice acyltransferase assay was performed with microsomes from yeast transformed with empty vector or plasmids expressing the indicated proteins in the absence or presence of 50 μm thimerosal. The amount of each individual deuterated PC species is expressed as the percentage of its LC/MS/MS signal relative to the endogenous 34:2 PC signal. A, microsomes from yeast expressing human MBOAT proteins. Data are normalized for MBOAT expression, and background activity present in yeast transformed with empty vector is subtracted. This background activity is shown in B. Data shown are from one experiment representative of two individual experiments. C, MBOAT5 acyltransferase assays conducted using radiolabeled lyso-PC and arachidonoyl-CoA either in the absence or in the presence of 50 μm thimerosal. Data shown are the average ± S.E. of two individual experiments conducted in duplicate. ^*, p < 0.005 (compared with control).