A 1.2kb BamHI/EagI fragment from upstream of the stg transcription unit is fused upstream of a stg promoter fragment from -31bp to -509bp which is fused upstream of Ecol\lacZHsp70Bb.HZ50.
In early embryo, expressed in mesectoderm, head, scattered cells in the ventral epidermis, and the tracheal placodes. Embryonic spatial expression also described in terms of mitotic domains.