Fig 1.

Enhanced intestinal epithelial cell migration and proliferation are LPA₁ dependent. (A) Migration of YAMC cells into the nude area at 24 h of 1 μM LPA treatment is shown. Cells were pretreated with 10 μM Ki16425 or transfected with shLPA₁ prior to LPA treatment. The extent of wound closure was quantified. Full recovery of the wound was considered 100%. *, P < 0.001; #, P < 0.001. n = 3. BSA (0.1%) was used as a control. The inset shows LPA₁ knockdown efficacy determined by real-time RT-PCR (shLPA₁; 69% decrease). (B) LPA-induced cell proliferation was determined by counting cells for up to 3 days. Cells were pretreated with Ki16425 or transfected with shLPA₁ as indicated. *, P < 0.01 versus shCont; #, P < 0.01 versus shCont plus LPA. Error bars represent the means ± SEM from three independent experiments involving triplicates. (C) The extent of migration at 12 h of LPA treatment was determined. *, P < 0.01; #, P < 0.01. n = 4. The inset shows overexpression of LPA₁ and LPA₂ in YAMC cells. (D) Lamellipodial extrusions in cells transfected with pCDH, shLPA₁, LPA₁, or LPA₂ are shown. Cells were fixed and labeled with phalloidin-Alexa Fluor 568 to identify the leading edge of lamellipodia (arrows). Dashed lines indicate the leading edges. n = 3. Bar, 20 μm. (E) Numbers of proliferating cells transfected with LPA₁ or LPA₂ were determined. *, P < 0.01 versus pCDH; #, P < 0.01 compared with pCDH plus LPA. n = 3.