Fig. 5.
Merging of lgl− rasV12 clones in tumors. The expression of engrailed (en, in red) marks the anterior or posterior compartment origin of the clones. The Top row shows two discs from the 7-min HS experiment. The disc in A and A′ is the typical case fixed 72 h after clone initiation, in which there are very few clones and these are small. The disc in B and B′ was fixed after 96 h and represents the unusual case in which the disc develops a tumor after 7 min of HS. Note that the tumor contains cells of anterior and posterior origin and therefore must have been formed by at least two clones. The Bottom row shows typical cases from the 15-min HS experiment. The 72-h AHS disc (C and C′) contains several clones, some anterior and some posterior. Note the closeness of some clones, suggesting they are about to merge. The 96-h AHS disc (D and D′) has a large tumor that contains cells of anterior and posterior origin.