Figure 6. LPA stimulates the activation of Src via Gαi2.

(A) LPA-mediated activation of Src involves Gαi2. SKOV3.ip cells were transiently transfected with either nonsense shRNA or shRNA that targeted Gαi2. After 24 hours, the transfected cells were serum starved for 16 hours and treated with 10 μM of LPA for 20 minutes along with untreated control groups. Lysates were subjected to immunoblot analysis using antibodies specific to Src phosphorylated on Tyr-419. The blot was stripped and probed for total Src to monitor expression levels and equal loading of proteins. A parallel blot was used to monitor for the silencing of Gαi2 using antibodies specific to Gαi2. The blot was stripped and re-probed with antibodies specific to GAPDH to monitor equal loading of proteins. (B) Constitutively activated Gαi2 stimulates Src. SKOV3.ip (2 × 10⁶) cells were transiently transfected with either vector control or with constitutively active Gαi2QL. After 48 hours, the transfectants were lysed and subjected to immunoblot analysis with antibodies specific to tyrosine-419 phosphorylated Src. The blot was stripped and re-probed for total Src. Expression of constitutively active Gαi2 was confirmed with antibodies specific to Gαi2. The blots were stripped and re-probed with antibodies to GAPDH to monitor equal loading of proteins. Presented results are from a typical experiment (n = 3).