Figure 1.

RecQL4, Mcm10 and Ctf4 interact with each other on chromatin and RecQL4 is required for the interaction between Mcm10 and Ctf4 on chromatin. (A) SF9 cells were infected with combinations of baculoviruses expressing RecQL4 (R4), Mcm10 (M10), and Ctf4 (C4), and incubated for 50 hr. Whole cell extracts were used for immunoprecipitations with antibodies against the indicated proteins or control IgG. Lanes 1, 4, 7, 10, 13, 16, 19, and 22 represent input material (10%) for each immunoprecipitation. (B) HeLa cells were transfected with GFP expressing vector or BiFC plasmids expressing RecQL4, Mcm10, and Ctf4 as indicated. After incubation for 24 hr, cells were washed with PBS containing 0.1 % Triton X-100, and cell fluorescence was examined. Pre- and post-treated images were obtained with live cells using a fluorescent microscope. (C) HeLa cells were transfected with siRNAs as indicated and incubated for 24 hr. Cells were then co-transfected with siRNAs and BiFC expression vectors as indicated. After incubation for 24 hr, the percent of cells showing positive interactions were counted. Each bar represents the mean value of 3 independent experiments; the error bar indicates the standard error observed between experiments.