Table 2. Interactions of dFS with TGF-β-type ligands of Drosophila.

Males expressing one of the seven ligands with the X-chromosomal A9-GAL4 were crossed to one copy (1x; columns 2-4) or two copies (2x; columns 5-7) of dFS. The number of males (columns 2 and 5) was used to calculate the expected number of females (columns 4 and 7). Co-expression of four ligands, dACT, MYO, DPP, and SCW, can significantly rescue a lethal line of dFS. While dACT can rescue 38% of females expressing two transgenic copies of dFS, increased levels of DPP and MYO only allow few animals to survive. In contrast, DAW decreases viability of a weak dFS line by 61% from 54% to 33% (bottom rows).

Ligand	Males without A9-GAL4	Females A9>ligand >dFS (1x)	Rescue females/ males		Males without A9-GAL4	Females A9>ligand >dFS (2x)	Rescue females/ males
No ligand	213	0	0.0%		39	0	0.0%
DPP	86	49	57.0%		69	2	3.0%
SCW	105	16	15.2%		52	0	0.0%
GBB	182	0	0.0%		161	0	0.0%
dACT	97	73	75.3%		171	65	38.0%
DAW	112	0	0.0%		160	0	0.0%
MYO	137	28	20.4%		149	5	3.4%
MAV	70	17	24.2%		77	0	0.0%
	Males without A9-GAL4	Females A9>ligand >weak dFS	Ratio females/ males
No ligand	66	36	54.5%
DAW	48	16	33.3%