RasGRP expressed in T cells.

Protein lysates were prepared from T-cell lines (T; Jurkat, human acute T-cell leukemia; ADOH, mouse T-helper cell hybridoma; BW5147, mouse T-cell lymphoma; SAKR, mouse T-cell lymphoma; EL4, mouse T-cell lymphoma; CEM, human acute T-cell lymphoblastic leukemia; YT-INDY, human NK-like T-cell leukemia; PEER, human T-cell lymphoblastic leukemia; MOLT4, human acute lymphoblastic T-cell leukemia), and from non–T-cell lines (non-T: FaDu, human pharynx squamous cell carcinoma; B65, mouse neuroblastoma; ED27, human chroriocarcinoma; MCF10A, human mammary epithelium; SK28 and WM39, human melanoma). Freshly isolated mouse thymocyctes (Th) were also examined. As controls, we studied rat2 cells and rat2 cells engineered to express RasGRP. Protein extracts were resolved by SDS/PAGE followed by immunoblotting with an antibody (H176) directed against the amino-terminus of RasGRP.