FIGURE 4.

TMD1 is sufficient to target mCherry to the ER. Segments of DGAT2 containing TMD1 and -2 (mCherry/TMD1 + 2), TMD1 (mCherry/TMD1), or TMD2 (mCherry/TMD2) were fused to the C terminus of mCherry. A, total cellular membranes and cytosol were isolated from COS-7 cells expressing mCherry/TMD1 + 2, mCherry/TMD1, mCherry/TMD2, or mCherry alone. Fractions were separated by SDS-PAGE and immunoblotted with anti-DsRed, anti-calnexin, and anti-GAPDH antibodies. B, COS-7 cells were transfected with mCherry/TMD1 + 2, mCherry/TMD1, mCherry/TMD2, or mCherry alone. After fixation and permeabilization, transfected cells were stained with anti-ACAT1 to visualize the ER. Scale bars, 10 μm.