Deletion of amino acids 172 to 216, en-derived region 3 (removes the most conserved portion of the entire eh1 homology plus additional sequences).
After a 15 minute heat shock 5-15% embryos fail to hatch. Embryonic cuticle shows no ftz-dependent defects.
Carried in plasmid "pEFEΔ3", expressed in S2 cells and competition for ftz binding sites on a Ecol\CAT reporter plasmid is studied.