FIGURE 2.

HP1α and HP1β, but not HP1γ, coprecipitate with MyoD in myoblasts. Nuclear extracts from growing myoblasts were used for immunoprecipitation with antibodies raised against MyoD, Suv39h1, or control beads (A) or against HP1α, HP1β, HP1γ, or normal mouse IgG as a negative control (B). The resulting precipitates were then subjected to Western blotting (immunoblot, IB) analysis for the presence of Suv39h1, MyoD, HP1α, HP1β, and HP1γ as indicated in A and B. Total input lysate was loaded in B to show that HP1γ is present in the inputs, even if it is not present in the IP. Lower panel of B, the faint signal obtained with anti-HP1 Western blotting in the control IgG IP corresponds to IgG light chain (noise).