Sp1 association with the SCL complex in vivo in hematopoietic cells.

Coimmunoprecipitations of endogenous proteins from TF-1 cell nuclear extracts were performed with the use of the antibodies indicated above each panel. Arrowheads point to specific bands that were revealed through Western blotting, with the antibodies indicated on the left. Inputs represent 5% (50 μg) of the amount used for each immunoprecipitation (1 mg), and the asterisks indicate immunoglobulin heavy and light chains. Note that GATA-1 is coimmunoprecipitated with α-GATA-1, α-SCL, and α-Sp1; Sp1 is immunoprecipitated by α-Sp1; SCL coprecipitates with α-SCL, α-Ldb-1, α-LMO2, and α-Sp1, but not with α-GFP or α-PU.1, while E2A is brought down by α-E2A and α-SCL.