Fig. 8. Actin bundles isolated from CaD39-AB-expressing cells contain much less force-expressed protein than that from CaD39-expressing cells. Lane 1, 39C15; lane 2, m5-8; lane 3, m4-65. (A) Western blot analysis of total protein extract from 39C15, m5-8 and m4-65 using C21 anti-CaD antibody. (B) SDS-PAGE analysis of tropomyosin-enriched actin bundles isolated from interphase cells of 39C15, m5-8 and m4-65. (C-E) Western blot analyses of isolated tropomyosin-enriched actin bundles with C21 antibody (C,E) and with CG3 anti-TM5 antibody (D). Despite the comparable CaD expression levels, the portion of the force-expressed protein associated with actin bundles was much less in both m5-8 and m4-65 cells than that in 39C15 cells. After calculating the differences in the initial cell numbers used for the actin bundle isolation and in the volumes loaded in the gel, the yield of actin bundles isolated from m4-65 cells was 2.2 times lower than that for 39C15 cells.