Fig 1: The expression of Best3 in myoblasts, muscle tissues and fibroblasts.(A) The expression of mouse Best3 in NIH3T3, myoblasts differentiated from satellite cells, myoblasts differentiated from C2C12 (4 days after confluency), skeletal muscle (SK) and heart was assessed by RT-PCR. Two sets of primers for mouse Best3 sequence (NM_001007583) were used. Alpha actin was used as an internal control. (B) Schematic presentation of full-length mouse Best3 and 2 alternatively spliced variants V1 and V2 (Best3V2). (C) Distinct distribution patterns of full-length Best3 and Best3V2. The ER was stained with PDI, the membrane ruffles were stained with an anti-caveolin 1 antibody, and some focal adhesions were visualized with GFP_FAK. Scale bar, 20 µm. (D) The expression of endogenous Best3 in differentiating myoblasts derived from satellite cells. The cells were also co-stained with a tropomyosin antibody to determine the levels of endogenous Tropomyosin. (E) The size of the endogenous Best3 proteins and its targeting to the plasma membrane in differentiating C2C12 myoblasts. Plasma membrane targeting was monitored via cell surface protein biotinylation. Whole proteins of skeletal muscle (SK) and C2C12 myoblasts were used as controls. (F) Best3 expression was analyzed in myoblasts differentiating from C2C12 cells on day 0 (D0), day 2 (D2) and day 4 (D4) by RT-PCR. M, DNA marker. The experiments were repeated 3 times.