Gsc transcript is expressed in two domains during embryogenesis. At stage 4,
Gsc transcript is expressed as a narrow dorsoanterior stripe, which assumes a horseshoe shape by stage 6. The horseshoe splits dorsally at stage 8, and by stage 14, cells expressing
Gsc transcript are located in the brain hemispheres. The second domain of expression begins at stage 9 at the anterior tip of the embryo, in cells which invaginate into the stomodeum. These cells abut the anterior midgut region at the end of germband retraction, and might contribute to the anterior foregut, the ring gland, and the stomodeal nervous system.
Gsc transcripts are first detected in a horseshoe pattern in the procephalic neurogenic region of blastoderm embryos. Later these cells delaminate in two groups and form a ventro-lateral sector of each brain hemisphere. At stage 10, a new expression domain appears in the foregut anlage and shortly after marks the stomodeum. This expression domain gives rise to a specific region of the foregut at the junction of the pharynx and esophagus, a part of the stomatogastric nervous system, and a part of the ring gland.
