To begin, transfect the stomach adenocarcinoma cells with TMEM200A Si-RNA and incubate for two days. Then, discard the cell culture medium from the wells and gently wash the cells two times with one milliliter of PBS. Place the cells on ice and add 150 microliters of pre-cooled radioimmune precipitation assay lysis buffer.
Using a plastic cell scraper, carefully detach the adhering cells from the dish and transfer the cell solution gently into a pre-cooled microcentrifuge tube. Then, centrifuge the cell lysate at 1.5 by 10 raised to the power four G for 10 minutes at four degrees Celsius, and transfer the supernatant to a new 1.5-milliliter microcentrifuge tube. Using a BCA protein assay kit, determine the protein content following the manufacturer's instructions.
Load 30 grams of protein from each sample onto a 10%SDS-PAGE gel. Run the gel at 80 volts for 0.5 hours, followed by 1.5 hours at 120 volts. Next, transfer the proteins from the gel to a 45-micrometer PVDF membrane at a constant current of 300 milliamperes for 1 to 1.5 hours.
Place the PVDF membrane on a shaker for three cycles of five minutes each. After shaking, add TBST to the container with the protein side facing up. Place the membrane in the blocking buffer for 30 minutes at room temperature.
Wash the membrane with TBST for three cycles of 10 minutes each. Incubate the membrane with primary antibodies overnight at four degrees Celsius. After washing the membrane three times with TBST, add a rabbit or mouse secondary antibody and incubate for one hour at room temperature.
Then, add ECL substrate to the PVDF membrane for 30 seconds and detect the signal using an imaging system. The efficiency of TMEM200A was significantly reduced in gastric cancer cell HGC-27 transfected with Si-RNA, compared to the non-transfected cells. The TMEM200A Si-RNA significantly inhibited the related proteins in epithelial mesenchymal transition, and affected the phosphorylation of AKT in the phosphoinositide 3-kinase signaling pathway.
