FIGURE 3.

Bacterial PTPMT1 functionally compensates for loss of yeast gep4 in vivo. A, wild-type murine, fly, and bacterial PTPMT1 complement the growth deficiency of GEP4-null cells. The expression levels of FLAG-tagged PTPMT1s and GEP4 are indicated by Western blot analysis. YPD, yeast extract-peptone-glucose medium; SCD, synthetic completed medium with dextrose; EtBr, ethidium bromide. CDC2 levels are shown as the loading control. Detection of steady state PGP (B) and CL (C) levels in gep4Δ yeast cells complemented with control plasmid or plasmids encoding PTPMT1 orthologs. Cells were labeled with [³²P]orthophosphate at 10μCi/ml for 12 h. Lipids were extracted, separated via TLC, and viewed by autoradiography. D, PGP and CL contents are determined by the ratio of ³²P incorporated into PGP versus total phospholipids, and represented as the mean ± S.D. from three independent experiments. **, p ≤ 0.01; *, p ≤ 0.05.