Production of Eμ-TCL1 transgenic (TG) mice. (a) Schematic representation of the construct used to generate the mice. Restriction sites: X, XhoI; S, SalI; E, EcoRV; B, BssHII. (b) Southern blot analysis of DNA isolated from the tails of the first TG progeny for both founders and non-TG control. (c) Immunoblot analysis on protein extracts from TG (F3 and F10) and non-TG (C = control) mouse tissues. 697 = pre-B leukemic cell line 697, which expresses high levels of Tcl1 protein (9). (d) TCL1 expression on gate subsets of splenic B cells. (Upper) Refers to the F3 progeny. (Lower) F10 progeny (Blue = TG, Red = non-TG).