Expression of RasGRP3 in the B-cell lineage and coexpression with PKC-θ in Ramos B cells. Cellular proteins in postnuclear supernatants (100 μg per sample) were immunoblotted with the anti-RasGRP3 antibody (top panel). The uppermost arrow indicates a nonspecific band. Lysates were also probed with an anti–PKC-θ antibody (bottom panel).