The AF2 helix has been removed.
ftz-f1ΔAF2.UAS/Scer\GAL4arm.PS partially rescues ftz-f1209
Only about a third of ftz-f1209 embryos rescued by ftz-f1ΔAF2.Scer\UAS (driven by Scer\GAL4arm.PS) show any rescue of the pair rule phenotype.