Table 1.

Percentage of tsl mutant embryos with anterior terminal structures upon expression of tsl in the BCs and/or the CCs

Genotype	Expression pattern of the Gal4 lines	Embryos with anterior terminal structures, %	n
UAS-tsl/+; CyO/+; tsl604HM		0	69
UAS-tsl/+; slboGal4/+; tsl604HM*	BCs, CCs, PFCs	100	121
UAS-tsl/+; tsl(G)Gal4/+; tsl604HM	BCs, PFCs	100	56
UAS-tsl/+; tsl(F)Gal4/+; tsl604HM	CCs (few and late)	100	39

Rescue of anterior terminal structures was scored by the complete formation of the dorsal bridge. n, Number of embryos.

*tsl overexpression with the slboGAL4 line generates many embryos with defects in head involution that could not be scored for the formation of the dorsal bridge. Embryos examined for anterior rescue (n = 121 of 218) are those with normal head involution. All experiments were done at 25°C.